Item 1. BUSINESS

GENERAL

We are a corporation incorporated under the laws of the state of Oklahoma, and our common stock is listed on the NYSE under the trading symbol “OKE.” We are a leading midstream service provider and own one of the nation’s premier natural gas liquids systems, connecting NGL supply in the Mid-Continent, Permian and Rocky Mountain regions with key market centers and an extensive network of natural gas gathering, processing, storage and transportation assets. We apply our core capabilities of gathering, processing, fractionating, transporting, storing and marketing natural gas and NGLs through vertical integration across the midstream value chain to provide our customers with premium services while generating consistent and sustainable earnings growth.

EXECUTIVE SUMMARY

Merger Transaction - On June 30, 2017, we completed the acquisition of all of the outstanding common units of ONEOK Partners that we did not already own. Prior to June 30, 2017, we and our subsidiaries owned all of the general partner interest, which included incentive distribution rights, and a portion of the limited partner interest, which together represented a 41.2 percent ownership interest in ONEOK Partners. The earnings of ONEOK Partners that are attributed to its units held by the public during the six months ended June 30, 2017, are reported as “Net income attributable to noncontrolling interests” in our Consolidated Statement of Income. Our general partner incentive distribution rights effectively terminated at the closing of the Merger Transaction.

Business Update and Market Conditions - We operate primarily fee-based businesses in each of our three reportable segments, and our consolidated earnings were nearly 90 percent fee-based in 2018. We are connected to supply in growing basins and have significant basin diversification, including the Williston, Permian, Powder River and DJ Basins and the STACK and SCOOP areas. While our Natural Gas Gathering and Processing and Natural Gas Liquids segments generate primarily fee-based earnings, those segments’ results of operations are exposed to volumetric risk. Our exposure to volumetric risk can result from declining well productivity, reduced drilling activity, severe weather disruptions, operational outages and ethane rejection. Commodity prices decreased in the fourth quarter 2018 and are expected to fluctuate in 2019. However, we do not expect supply volumes in our three business segments to be materially impacted.

Volumes increased across our operating regions in our Natural Gas Gathering and Processing and Natural Gas Liquids segments in 2018, compared with 2017, as a result of improved crude oil prices, producers experiencing improved drilling economics and continued improvements in production due to enhanced completion techniques. In addition, we experienced increased demand for NGL products from petrochemical and NGL export facilities in the Gulf Coast. We have spent approximately $2 billion of our announced $6 billion of capital-growth projects that include NGL pipelines, NGL fractionators and natural gas processing plants supported by a combination of long-term primarily fee-based contracts, volume commitments and/or acreage dedications. Our NGL projects in the Gulf Coast also allow flexibility to construct additional NGL fractionators, storage and potentially, new export facilities in the future. We expect these projects to meet the needs of natural gas processors and producers and the petrochemical industry that require additional midstream infrastructure to accommodate increasing supply and demand in the areas in which we operate.

For most of 2018, we benefited from favorable NGL price differentials as available pipeline and fractionation capacity in and between the Conway, Kansas, and Mont Belvieu, Texas, market centers tightened due to growing NGL supply from the Mid-Continent and Rocky Mountain regions, combined with increased petrochemical and NGL export demand in the Gulf Coast, resulting in higher earnings from our Natural Gas Liquids segment’s optimization and marketing activities. In the fourth quarter 2018, these differentials narrowed resulting from seasonality of supply and demand in the Mid-Continent region, lower commodity prices and additional pipeline and fractionation capacity resulting from operational efficiencies. While we expect NGL price differentials to be volatile in 2019, we expect that they will be wider than historical norms due to additional demand in the Gulf Coast, additional NGL supply growth in the Mid-Continent region and continuing fractionation and pipeline constraints. We expect these wider NGL price differentials to continue until announced NGL pipeline and fractionation infrastructure projects, including our Arbuckle II pipeline, are completed in early 2020.

Rocky Mountain Region - We expect each of our business segments to benefit from increased production in this region, which includes the Williston, Powder River and DJ Basins. In our Natural Gas Gathering and Processing segment, our gathering and processing capacity of 1.1 Bcf/d in this region allows us to capture natural gas from the more than 1 million acres dedicated to us in the core of the Williston Basin and approximately 3 million acres throughout the entire basin. Natural gas gathered and

processed volumes in this region increased in 2018, compared with 2017, due primarily to new supply and completion of growth projects. With continued volume growth expected due to improved drilling economics and producer efficiencies, we are constructing our Demicks Lake I and Demicks Lake II natural gas processing plants. These projects will provide an additional 400 MMcf/d of processing capacity in the core of the Williston Basin, helping producers meet North Dakota’s natural gas capture targets and adding incremental NGLs to our NGL gathering system and supplying natural gas to our 50 percent-owned Northern Border Pipeline. Our Demicks Lake I plant is expected to reach capacity soon after its completion in the fourth quarter 2019 due to more than 250 MMcf/d of natural gas currently flaring on our dedicated acreage due primarily to lack of processing capacity. In our Natural Gas Liquids segment, the volume growth in this region has resulted in the Overland Pass pipeline, of which we own 50 percent, and our Bakken NGL pipeline operating at or near full capacities. We are constructing our Elk Creek pipeline to support expected supply growth and provide needed infrastructure to transport NGLs out of the region to the Mid-Continent with connectivity to the Gulf Coast. We expect the southern section of our Elk Creek pipeline to be in service as early as the third quarter 2019, which would allow NGL production from the Powder River Basin to be transported on this section of pipeline before the entire Elk Creek pipeline project is complete. As a result, we expect capacity will be available on our Bakken NGL pipeline to transport additional NGL volumes from the Williston Basin.

STACK and SCOOP - As producers continue to develop the STACK and SCOOP areas in Oklahoma, we expect increased demand for our services from producers that need incremental takeaway capacity for natural gas and NGLs out of the Mid-Continent region. In our Natural Gas Gathering and Processing segment, natural gas gathered and processed volumes increased in 2018, compared with 2017, due to increased producer activity in these areas, where we have sizable acreage dedications. In response to this increased activity, we completed the 200 MMcf/d expansion of our Canadian Valley natural gas processing plant, which increased our total processing capacity to 1.2 Bcf/d in these areas. In our Natural Gas Liquids segment, we are the largest NGL takeaway provider in the STACK and SCOOP areas, where NGL volumes significantly increased in 2018, compared with 2017. To accommodate these volumes, we completed the expansion of our existing Sterling III pipeline and are constructing our Arbuckle II pipeline to support expected supply growth and transport NGLs to the Gulf Coast market. We also announced plans to construct an extension of our Arbuckle II pipeline further north along with additional NGL gathering infrastructure, as well as an expansion of our Arbuckle II pipeline by 100 MBbl/d to a total capacity of 500 MBbl/d. In our Natural Gas Pipelines segment, we are connected to more than 30 natural gas processing plants in Oklahoma. In the first quarter 2018, we completed the 100 MMcf/d expansion of our ONEOK Gas Transportation pipeline to provide increased westbound transportation services from the STACK area. An additional 100 MMcf/d westbound expansion from the STACK area to multiple interstate pipeline delivery points in western Oklahoma was also completed in 2018. In the first quarter 2019, we expect to complete an additional expansion to our ONEOK Gas Transportation pipeline with a 150 MMcf/d eastbound expansion from the STACK and SCOOP areas to an eastern Oklahoma interstate pipeline delivery point.

Permian Basin - We expect our Natural Gas Liquids and Natural Gas Pipelines business segments to benefit from increased production in the Permian Basin from the highly productive Delaware and Midland Basins. In our Natural Gas Liquids segment, we are well-positioned in the Permian Basin through our West Texas LPG pipeline system, which was recently extended into the core of the Delaware Basin through construction of a 120-mile pipeline lateral and a 40 MBbl/d expansion of the mainline. In September 2018, we announced a second expansion of our West Texas LPG pipeline system, which will increase the mainline capacity out of the Permian Basin by 80 MBbl/d as well as connect our West Texas LPG pipeline with our Arbuckle II pipeline, which is currently under construction. These projects are expected to position our West Texas LPG pipeline system for significant future NGL volume growth and are backed by long-term acreage and/or plant dedications. In our Natural Gas Pipelines segment, our Roadrunner joint venture and our WesTex pipeline are well-positioned to serve growth in the Permian Basin. The Roadrunner pipeline connects with our existing natural gas pipeline and storage infrastructure in Texas and, together with our completed WesTex intrastate natural gas pipeline expansion project, creates future opportunities for us to deliver natural gas supply to Mexico and transport natural gas to other markets in the region. We completed the expansion of our WesTex Transmission system by 300 MMcf/d from the Permian Basin to interstate pipeline delivery points in the Texas Panhandle. We also completed an expansion project on our Roadrunner joint venture to make the pipeline bidirectional, which will result in approximately 1.0 Bcf/d of eastbound transportation capacity from the Delaware Basin to the Waha area.

Gulf Coast - Demand for NGLs is expected to continue to increase at the Mont Belvieu, Texas, NGL market center as new world-scale ethylene production projects, petrochemical plant expansions and NGL export facilities continue to be completed. NGL supply growth and new NGL pipelines recently completed or being constructed, including our Elk Creek pipeline, Arbuckle II pipeline and West Texas LPG pipeline projects, are increasing NGL deliveries to Mont Belvieu, Texas. While we have significant NGL fractionation and storage assets in this area, additional capacity is needed to accommodate expected volume growth. To respond to this need, we are constructing two additional 125 MBbl/d fractionators with related infrastructure in Mont Belvieu, Texas, MB-4 and MB-5, which are both fully contracted. Following the completion of MB-4 and MB-5, we expect our Gulf Coast NGL fractionation capacity to be approximately 600 MBbl/d and more than 1 million Bbl/d across our entire system. Our MB-5 project also includes system expansions that provide infrastructure

capacity to support additional assets as we continue to evaluate opportunities for fractionation, storage and export facilities to meet the supply and demand for NGLs.

See Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, for more information on our growth projects, results of operations, liquidity and capital resources.

BUSINESS STRATEGY

Our primary business strategy is to maintain prudent financial strength and flexibility while growing our fee-based earnings and dividends per share with a focus on safe, reliable, environmentally responsible, legally compliant and sustainable operations for our customers, employees, contractors and the public through the following:

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Operate in a safe, reliable, environmentally responsible and sustainable manner - environmental, safety and health issues continue to be a primary focus for us, and our emphasis on personal and process safety has produced improvements in the key indicators we track. We also continue to look for ways to reduce our environmental impact by conserving resources and utilizing more efficient technologies;

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Maintain prudent financial strength and flexibility while growing our fee-based earnings, dividends per share and cash flows from operations in excess of dividends paid - we operate primarily fee-based businesses in each of our three reportable segments. We continue to invest in organic growth projects to expand in our existing operating regions and provide a broad range of services to crude oil and natural gas producers and end-use markets. In 2018, we paid dividends of $3.245 per share, an increase of 19 percent compared with the prior year. Our dividend increase and expected future dividend growth is due primarily to our growth projects. We have spent approximately $2 billion of our announced $6 billion of capital-growth projects that are supported by a combination of long-term primarily fee-based contracts, minimum volume commitments and acreage dedications;

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Manage our balance sheet and maintain investment-grade credit ratings - we seek to maintain investment-grade credit ratings. We expect to benefit from increasing cash flows from operations in 2019. At December 31, 2018, we had $2.5 billion of borrowing capacity available under our $2.5 Billion Credit Agreement and $950 million of borrowings available under our $1.5 Billion Term Loan Agreement; and

•	Attract, select, develop, motivate, challenge and retain a diverse group of employees to support strategy execution - we continue to execute on our recruiting strategy that targets professional and field personnel in our operating areas. We also continue to focus on employee development efforts with our current employees and monitor our benefits and compensation package to remain competitive.

NARRATIVE DESCRIPTION OF BUSINESS

We report operations in the following business segments:

•	Natural Gas Gathering and Processing;

•	Natural Gas Liquids; and

•	Natural Gas Pipelines.

Natural Gas Gathering and Processing

Overview - Our Natural Gas Gathering and Processing segment provides midstream services to producers in North Dakota, Montana, Wyoming, Kansas and Oklahoma. Raw natural gas is typically gathered at the wellhead, compressed and transported through pipelines to our processing facilities. Processed natural gas, usually referred to as residue natural gas, is then recompressed and delivered to natural gas pipelines, storage facilities and end users. The NGLs separated from the raw natural gas are sold and delivered through natural gas liquids pipelines to fractionation facilities for further processing.

Rocky Mountain region - The Williston Basin is located in portions of North Dakota and Montana and includes the oil-producing, NGL-rich Bakken Shale and Three Forks formations, and is an active drilling region. Our completed capital-growth projects in the Williston Basin have increased our gathering and processing capacity to more than 1.0 Bcf/d and allow us to capture increased natural gas production from new wells and previously flared natural gas production.

The Powder River Basin is primarily located in Wyoming, which includes the NGL-rich Niobrara Shale and Frontier, Turner and Sussex formations where we provide gathering and processing services to customers in the eastern portion of Wyoming.

Mid-Continent region - The Mid-Continent region is an active drilling region and includes the oil-producing, NGL-rich STACK and SCOOP areas and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations of Oklahoma and Kansas; and the Hugoton and Central Kansas Uplift Basins of Kansas.

Sources of Earnings - Earnings for this segment are derived primarily from commodity sales and service contracts. For commodity sales, we contract to deliver residue natural gas, condensate and/or unfractionated NGLs to downstream customers at a specified delivery point. Our sales of NGLs are primarily to our affiliate in the Natural Gas Liquids segment. The following are our types of services contracts:

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POP with fee contracts with no producer take-in-kind rights - We purchase raw natural gas and charge contractual fees for providing midstream services, which include gathering, treating, compressing and processing the producer’s natural gas. After performing these services, we sell the commodities and remit a portion of the commodity sales proceeds to the producer less our contractual fees. This type of contract represented 60 percent and 62 percent of supply volumes in this segment for 2018 and 2017, respectively. Upon adoption of Topic 606, the contractual fees we charge producers on these POP with fee contracts are recorded as a reduction to the commodity purchase price in cost of sales and fuel. In 2017 and prior periods, we recorded these fees as services revenue.

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POP with fee contracts with producer take-in-kind rights - We purchase a portion of the raw natural gas stream, charge fees for providing the midstream services listed above, return primarily the residue natural gas to the producer, sell the remaining commodities and remit a portion of the commodity sales proceeds to the producer less our contractual fees. This type of contract represented 36 percent and 34 percent of supply volumes in this segment for 2018 and 2017, respectively.

•	Fee-only - Under this type of contract, we charge a fee for the midstream services we provide, based on volumes gathered, processed, treated and/or compressed. Our fee-only contracts represented 4 percent of supply volumes in this segment in 2018 and 2017.

Property - Our Natural Gas Gathering and Processing segment owns the following assets:

•	11,500 miles and 7,700 miles of natural gas gathering pipelines in the Mid-Continent and Rocky Mountain regions, respectively;

•	ten natural gas processing plants with 1.0 Bcf/d of processing capacity in the Mid-Continent region, and 11 natural gas processing plants with 1.1 Bcf/d of processing capacity in the Rocky Mountain region; and

•	15 MBbl/d of natural gas liquids fractionation capacity at various natural gas processing plants in the Rocky Mountain region.

In addition, we have access to up to 200 MMcf/d of processing capacity in the Mid-Continent region through a long-term processing services agreement with an unaffiliated third party.

We are in the process of constructing our Demicks Lake I and Demicks Lake II natural gas processing plants. These projects will provide an additional 400 MMcf/d of processing capacity in the core of the Williston Basin.

Utilization - The utilization rates for our natural gas processing plants were 83 percent and 79 percent for 2018 and 2017, respectively. We calculate utilization rates using a weighted-average approach, adjusting for the dates that assets were placed in service.

Unconsolidated Affiliates - Our Natural Gas Gathering and Processing segment includes the following unconsolidated affiliates:

•	49 percent ownership in Bighorn Gas Gathering, which gathers coal-bed methane produced in the Powder River Basin;

•	37 percent ownership in Fort Union Gas Gathering, which gathers coal-bed methane produced in the Powder River Basin and delivers it to the interstate pipeline system;

•	35 percent ownership interest in Lost Creek Gathering Company, which gathers natural gas produced from conventional dry natural gas wells in the Wind River Basin of central Wyoming and delivers it to the interstate pipeline system; and

•	10 percent ownership interest in Venice Energy Services Co., a natural gas processing facility near Venice, Louisiana.

See Note M of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of our unconsolidated affiliates.

Government Regulation - The FERC traditionally has maintained that a natural gas processing plant is not a facility for the transportation or sale of natural gas in interstate commerce and, therefore, is not subject to jurisdiction under the Natural Gas Act. Although the FERC has made no specific declaration as to the jurisdictional status of our natural gas processing operations or facilities, our natural gas processing plants are primarily involved in extracting NGLs and, therefore, are exempt

from FERC jurisdiction. The Natural Gas Act also exempts natural gas gathering facilities from the jurisdiction of the FERC. We believe our natural gas gathering facilities and operations meet the criteria used by the FERC for nonjurisdictional natural gas gathering facility status. Interstate transmission facilities remain subject to FERC jurisdiction. The FERC has historically distinguished between these two types of facilities, either interstate or intrastate, on a fact-specific basis. We transport residue natural gas from certain of our natural gas processing plants to interstate pipelines in accordance with Section 311(a) of the Natural Gas Policy Act. Oklahoma, Kansas, Wyoming, Montana and North Dakota also have statutes regulating, to varying degrees, the gathering of natural gas in those states. In each state, regulation is applied on a case-by-case basis if a complaint is filed against the gatherer with the appropriate state regulatory agency.

See further discussion in the “Regulatory, Environmental and Safety Matters” section.

Natural Gas Liquids

Overview - Our Natural Gas Liquids segment owns and operates facilities that gather, fractionate, treat and distribute NGLs and store NGL products, primarily in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region, which includes the Williston, Powder River and DJ Basins, where we provide midstream services to producers of NGLs and deliver those products to the two primary market centers, one in the Mid-Continent in Conway, Kansas, and the other in the Gulf Coast in Mont Belvieu, Texas. We own or have an ownership interest in FERC-regulated natural gas liquids gathering and distribution pipelines in Oklahoma, Kansas, Texas, New Mexico, Montana, North Dakota, Wyoming and Colorado, and terminal and storage facilities in Missouri, Nebraska, Iowa and Illinois. We also own FERC-regulated natural gas liquids distribution pipelines in Kansas, Missouri, Nebraska, Iowa, Illinois and Indiana that connect our Mid-Continent assets with Midwest markets, including Chicago, Illinois. A portion of our ONEOK North System transports refined petroleum products, including unleaded gasoline and diesel, from Kansas to Iowa. The majority of the pipeline-connected natural gas processing plants in Oklahoma, Kansas and the Texas Panhandle are connected to our natural gas liquids gathering systems. We own and operate truck- and rail-loading and -unloading facilities connected to our natural gas liquids fractionation and pipeline assets.

Most natural gas produced at the wellhead contains a mixture of NGL components, such as ethane, propane, iso-butane, normal butane and natural gasoline. The NGLs that are separated from the natural gas stream at natural gas processing plants remain in a mixed, unfractionated form until they are gathered, primarily by pipeline, and delivered to fractionators where the NGLs are separated into NGL products. These NGL products are then stored or distributed to our customers, such as petrochemical manufacturers, heating fuel users, ethanol producers, refineries, exporters and propane distributors.

Sources of Earnings - Earnings for our Natural Gas Liquids segment are derived primarily from commodity sales and fee-based services. We also purchase NGLs and condensate from third parties, as well as from our Natural Gas Gathering and Processing segment. Our business activities are categorized as exchange services, transportation and storage services, and optimization and marketing, which are defined as follows:

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Exchange services - We utilize our assets to gather, transport, treat and fractionate unfractionated NGLs, thereby converting them into marketable NGL products delivered to a market center or customer-designated location. Many of these exchange volumes are under contracts with minimum volume commitments that provide a minimum level of revenues regardless of volumetric throughput. Our exchange services activities are primarily fee-based and include some rate-regulated tariffs; however, we also capture certain product price differentials through the fractionation process.

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Transportation and storage services - We transport NGL products and refined petroleum products, primarily under FERC-regulated tariffs. Tariffs specify the maximum rates we may charge our customers and the general terms and conditions for transportation service on our pipelines. Our storage activities consist primarily of fee-based NGL storage services at our Mid-Continent and Gulf Coast storage facilities.

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Optimization and marketing - We utilize our assets, contract portfolio and market knowledge to capture location, product and seasonal price differentials through the purchase and sale of NGLs and NGL products. We primarily transport NGL products between Conway, Kansas, and Mont Belvieu, Texas, to capture the location price differentials between the two market centers. Our marketing activities also include utilizing our natural gas liquids storage facilities to capture seasonal price differentials. A growing portion of our marketing activities serves truck and rail markets. Our isomerization activities capture the price differential when normal butane is converted into the more valuable iso-butane at our isomerization unit in Conway, Kansas.

In many of our exchange services contracts, we purchase the unfractionated NGLs at the tailgate of the processing plant and deduct contractual fees related to the transportation and fractionation services we must perform before we can sell them as NGL products. Upon adoption of Topic 606, the contractual fees we charge are now recorded as a reduction to the commodity purchase price in cost of sales and fuel. In 2017 and prior periods, we recorded these fees as exchange services revenue. To the

extent we hold unfractionated NGLs in inventory, the related contractual fees previously recorded in services revenue when NGLs were received on our system will not be recognized until the unfractionated inventory is fractionated and sold.

Property - Our Natural Gas Liquids segment owns the following assets:

Region/Asset	Miles of Pipeline			Capacity
Gathering Pipelines (a)				(MBbl/d)
Rocky Mountain Region	846			135
Mid-Continent Region	3,760			1,161
West Texas LPG System	2,849			285
Total	7,455			1,581
Distribution Pipelines (b)
Sterling Pipelines	1,804			458
ONEOK North System	1,704			213
Other	949			595
Total	4,457			1,266

(a) - Includes 4,545 miles of FERC-regulated pipelines with peak capacity of 683 MBbl/d.

(b) - Includes 4,290 miles of FERC-regulated pipelines with peak capacity of 1,200 MBbl/d.

Region/Asset	Number of Facilities			Capacity
Facilities				(MBbl/d)
Gulf Coast Region Fractionators (a)	3			278
Mid-Continent Region Fractionators (a)	4			521
Isomerization Unit	1			9
Ethane/Propane Splitter	1			40
Total	9			848
Storage and Terminals				(MMBbl)
NGL Storage	6			22.2
ONEOK North System Terminals	8			1.0
Total	14			23.2

(a) - Includes interest in our proportional share of operating capacity.

In addition, we lease 3.8 MMBbl of combined NGL storage capacity at facilities in Kansas and Texas and have access to 60 MBbl/d of natural gas liquids fractionation capacity in the Gulf Coast through a fractionation service agreement.

We are in the process of constructing the following assets:

Region/Asset	Miles of Pipeline			Capacity
Gathering Pipelines				(MBbl/d)
Rocky Mountain Region	900			240
Mid-Continent Region	530			500
West Texas LPG System	—			80
Total	1,430			820
Facilities
Gulf Coast Region Fractionators (two locations)				250

Utilization - The utilization rates for our various assets, including leased assets, have been impacted by ethane rejection. The utilization rates for 2018 and 2017, respectively, were as follows:

•	our natural gas liquids gathering pipelines were 78 percent and 75 percent;

•	our natural gas liquids distribution pipelines were 59 percent and 57 percent; and

•	our natural gas liquids fractionators were 85 percent and 74 percent.

We calculate utilization rates using a weighted-average approach, adjusting for the dates that assets were placed in service. Our fractionation utilization rate reflects approximate proportional capacity associated with our ownership interests.

Unconsolidated Affiliates - Our Natural Gas Liquids segment includes the following unconsolidated affiliates:

•	50 percent ownership interest in Overland Pass Pipeline Company, which operates an interstate natural gas liquids pipeline system extending 760 miles, originating in Wyoming and Colorado and terminating in Kansas;

•	50 percent ownership interest in Chisholm Pipeline Company, which operates an interstate natural gas liquids pipeline system extending 185 miles from origin points in Oklahoma and terminating in Kansas; and

•	50 percent ownership interest in Heartland Pipeline Company, which operates a terminal and pipeline system that transports refined petroleum products in Kansas, Nebraska and Iowa.

See Note M of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of unconsolidated affiliates.

Government Regulation - The operations and revenues of our natural gas liquids pipelines are regulated by various state and federal government agencies. Our interstate natural gas liquids pipelines are regulated by the FERC, which has authority over the terms and conditions of service; rates, including depreciation and amortization policies; and initiation of service. In Oklahoma, Kansas and Texas, certain aspects of our intrastate natural gas liquids pipelines that provide common carrier service are subject to the jurisdiction of the OCC, KCC and RRC, respectively.

See further discussion in the “Regulatory, Environmental and Safety Matters” section.

Natural Gas Pipelines

Overview - Our Natural Gas Pipelines segment provides transportation and storage services to end users through its wholly owned assets and its 50 percent ownership interests in Northern Border Pipeline and Roadrunner.

Interstate Pipelines - Our interstate pipelines are regulated by the FERC and are located in North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Kentucky, Tennessee, Oklahoma, Texas and New Mexico. Our interstate pipeline companies include:

•	Midwestern Gas Transmission, which is a bidirectional system that interconnects with Tennessee Gas Transmission Company’s pipeline near Portland, Tennessee, and with several interstate pipelines that have access to both the Utica Shale and the Marcellus Shale at the Chicago Hub near Joliet, Illinois;

•	Viking Gas Transmission, which is a bidirectional system that interconnects with a TransCanada Corporation pipeline at the United States border near Emerson, Canada, and ANR Pipeline Company near Marshfield, Wisconsin;

•	Guardian Pipeline, which interconnects with several pipelines at the Chicago Hub near Joliet, Illinois, and with local natural gas distribution companies in Wisconsin; and

•	OkTex Pipeline, which has interconnections with several pipelines in Oklahoma, Texas and New Mexico.

Intrastate Pipelines - Our intrastate natural gas pipeline assets in Oklahoma transport natural gas through the state and have access to the major natural gas production areas in the Mid-Continent region, which include the STACK and SCOOP areas and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations. In Texas, our intrastate natural gas pipelines are connected to the major natural gas producing formations in the Texas Panhandle, including the Granite Wash formation and Delaware and Midland Basins in the Permian Basin. These pipelines are capable of transporting natural gas throughout the western portion of Texas, including the Waha area where other pipelines may be accessed for transportation to western markets, exports to Mexico, the Houston Ship Channel market to the east and the Mid-Continent market to the north. Our intrastate natural gas pipeline assets also have access to the Hugoton and Central Kansas Uplift Basins in Kansas.

Sources of Earnings - Earnings in this segment are derived primarily from transportation and storage services.

Our transportation earnings are primarily fee-based from the following types of services:

•	Firm service - Customers reserve a fixed quantity of pipeline capacity for a specified period of time, which obligates the customer to pay regardless of usage. Under this type of contract, the customer pays a monthly fixed fee and

incremental fees, known as commodity charges, which are based on the actual volumes of natural gas they transport or store. Under the firm service contract, the customer generally is guaranteed access to the capacity they reserve.

•	Interruptible service - Under interruptible service transportation agreements, the customer may utilize available capacity after firm service requests are satisfied. The customer is not guaranteed use of our pipelines unless excess capacity is available.

Our regulated natural gas transportation services contracts are based upon rates stated in the respective tariffs, which have generally been established through shipper specific negotiation, discounts and negotiated settlements. The rates are filed with FERC or the appropriate state jurisdictional agencies. In addition, customers typically are assessed fees, such as a commodity charge, and we may retain a percentage or specified volume of natural gas in-kind based on the natural gas volumes transported.

Our storage earnings are primarily fee-based from the following types of services:

•	Firm service - Customers reserve a specific quantity of storage capacity, including injection and withdrawal rights, and generally pay fixed fees based on the quantity of capacity reserved plus an injection and withdrawal fee. Firm storage contracts typically have terms longer than one year.

•	Park-and-loan service - An interruptible storage service offered to customers providing the ability to park (inject) or loan (withdraw) natural gas into or out of our storage, typically for monthly or seasonal terms. Customers reserve the right to park or loan natural gas based on a specified quantity, including injection and withdrawal rights when capacity is available.

Upon adoption of Topic 606, we record retained fuel charges as a reduction to cost of sales and fuel that would have been recorded as transportation or storage revenue prior to adoption.

We own natural gas storage facilities located in Texas and Oklahoma that are connected to our intrastate natural gas pipelines. We also have underground natural gas storage facilities in Kansas.

Property - Our Natural Gas Pipelines segment owns the following assets:

•	1,500 miles of FERC-regulated interstate natural gas pipelines with 3.5 Bcf/d of peak transportation capacity;

•	5,200 miles of state-regulated intrastate transmission pipelines with peak transportation capacity of 4.1 Bcf/d; and

•	52.2 Bcf of total active working natural gas storage capacity.

Our storage includes two underground natural gas storage facilities in Oklahoma, two underground natural gas storage facilities in Kansas and two underground natural gas storage facilities in Texas.

Utilization - Our natural gas pipelines were 96 and 94 percent subscribed in 2018 and 2017, respectively, and our natural gas storage facilities were 64 percent subscribed in both 2018 and 2017, respectively.

Unconsolidated Affiliates - Our Natural Gas Pipelines segment includes the following unconsolidated affiliates:

•	50 percent interest in Northern Border Pipeline, which owns a FERC-regulated interstate pipeline that transports natural gas from the Montana-Saskatchewan border near Port of Morgan, Montana, and the Williston Basin in North Dakota to a terminus near North Hayden, Indiana.

•	50 percent interest in Roadrunner, a bidirectional pipeline, which has the capacity to transport 570 MMcf/d of natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas, and will have capacity to transport approximately 1.0 Bcf/d of natural gas from the Delaware Basin to the Waha area. We are the operator of Roadrunner.

See Note M of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of unconsolidated affiliates.

Government Regulation - Interstate - Our interstate natural gas pipelines are regulated under the Natural Gas Act, which gives the FERC jurisdiction to regulate virtually all aspects of this business, such as transportation of natural gas, rates and charges for services, construction of new facilities, depreciation and amortization policies, acquisition and disposition of facilities, and the initiation and discontinuation of services.

Intrastate - Our intrastate natural gas pipelines in Oklahoma, Kansas and Texas are regulated by the OCC, KCC and RRC, respectively, and by the FERC under the Natural Gas Policy Act for certain services where we deliver natural gas into FERC

regulated natural gas pipelines. While we have flexibility in establishing natural gas transportation rates with customers, there is a maximum rate that we can charge our customers in Oklahoma and Kansas and for the services regulated by the FERC. In Texas and Kansas, natural gas storage may be regulated by the state and by the FERC for certain types of services. In Oklahoma, natural gas storage operations are not subject to rate regulation by the state, and we have market-based rate authority from the FERC for certain types of services.

See further discussion in the “Regulatory, Environmental and Safety Matters” section.

Market Conditions and Seasonality

Supply and Demand - Supply for each of our segments depends on crude oil and natural gas drilling and production activities, which are driven by the strength of the economy; the decline rate of existing production; producer firm commitments to transportation pipelines; natural gas, crude oil and NGL prices; or the demand for each of these products from end users.

Demand for gathering and processing services is dependent on natural gas production by producers in the regions in which we operate. State requirements in North Dakota for producers to reduce natural gas flaring have increased the need for our services to capture, gather and process natural gas, and we are responding by constructing assets, such as our announced Demicks Lake I and Demicks Lake II natural gas processing plants. Demand for NGLs and the ability of natural gas processors to successfully and economically sustain their operations affect the volume of unfractionated NGLs produced by natural gas processing plants, thereby affecting the demand for NGL gathering, transportation and fractionation services. Natural gas and NGL products are affected by economic conditions and the demand associated with the various industries that utilize the commodities, such as butanes and natural gasoline used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil. Ethane, propane, normal butane and natural gasoline are also used by the petrochemical industry to produce chemical products, such as plastic, rubber and synthetic fibers. Propane is also used to heat homes and businesses. Demand for NGLs continues to increase at the Mont Belvieu, Texas, NGL market center as new world-scale ethylene production projects, petrochemical plant expansions and NGL export facilities continue to be completed. End-users of residue natural gas include large commercial and industrial customers, natural gas and electric utilities serving individual consumers and similar international markets through liquefied natural gas (LNG) exports.

Commodity Prices - Our earnings are primarily fee-based in all three of our segments. In our Natural Gas Gathering and Processing segment, we are exposed to limited commodity price risk as a result of retaining a portion of the commodity sales proceeds associated with our POP with fee contracts. In our Natural Gas Liquids segment, we are exposed to market risk associated with changes in the price of NGLs; the location differential between the Mid-Continent, Chicago, Illinois, and Gulf Coast regions; and the relative price differential between natural gas, NGLs and individual NGL products, which affect our NGL purchases and sales, and our exchange services, transportation and storage services, and optimization and marketing financial results. NGL storage revenue may be affected by price volatility and forward pricing of NGL physical contracts versus the price of NGLs on the spot market. In our Natural Gas Pipelines segment, we are exposed to market risk associated with (i) changes in the price of natural gas, which impact our fuel costs and retained fuel in-kind received for our services; (ii) interruptible contracts or when existing firm contracts expire and are subject to renegotiation with customers that have competitive alternatives, which affect our transportation revenues; and (iii) the differential between forward pricing of natural gas physical contracts and the price of natural gas on the spot market, which affects our natural gas storage revenue.

See additional discussion regarding our commodity price risk and related hedging activities under “Commodity Price Risk” in Part II, Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Seasonality - Cold temperatures usually increase demand for natural gas and certain NGL products, such as propane, the main heating fuels for homes and businesses. Warm temperatures usually increase demand for natural gas used in gas-fired electric generators for residential and commercial cooling, as well as agriculture-related equipment like irrigation pumps and crop dryers. Demand for butanes and natural gasoline, which are primarily used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil, are also subject to some variability during seasonal periods when certain government restrictions on motor fuel blending products change. During periods of peak demand for a certain commodity, prices for that product typically increase.

Extreme weather conditions, seasonal temperature changes and the impact of temperature and humidity on the mechanical abilities of the processing equipment impact the volumes of natural gas gathered and processed and NGL volumes gathered, transported and fractionated. Power interruptions and inaccessible well sites as a result of severe storms or freeze-offs, a phenomenon where water produced from natural gas freezes at the wellhead or within the gathering system, may cause a temporary interruption in the flow of natural gas and NGLs.

In our Natural Gas Pipelines segment, natural gas storage is necessary to balance the relatively steady natural gas supply with the seasonal demand of residential, commercial and electric-generation users.

Competition - We compete for natural gas and NGL supply with other midstream companies and major integrated oil companies and independent exploration and production companies that have gathering and processing assets, fractionators, intrastate and interstate pipelines and storage facilities. The factors that typically affect our ability to compete for natural gas and NGL supply are:

•	quality of services provided;

•	producer drilling activity;

•	proceeds remitted and/or fees charged under our contracts;

•	proximity of our assets to natural gas and NGL supply areas and markets;

•	location of our assets relative to those of our competitors;

•	efficiency and reliability of our operations;

•	receipt and delivery capabilities for natural gas and NGLs that exist in each pipeline system, plant, fractionator and storage location;

•	the petrochemical industry’s level of capacity utilization and feedstock requirements;

•	current and forward natural gas and NGL prices; and

•	cost of and access to capital.

We have responded by making capital investments to access and connect new supplies with end-user demand; increasing gathering, processing, fractionation and pipeline capacity; increasing storage, withdrawal and injection capabilities; and reducing operating costs so that we compete effectively. Our competitors also continue to invest in midstream infrastructure to address the growing natural gas and NGL supply and market demand. Our and our competitors’ infrastructure projects provide midstream services across our operating regions, which may affect commodity prices and compete with and could displace supply volumes from the Mid-Continent and Rocky Mountain regions and Permian Basin where our assets are located. We believe our assets are located strategically, connecting diverse supply areas to market centers.

Customers - Our Natural Gas Gathering and Processing and Natural Gas Liquids segments derive services revenue from major and independent crude oil and natural gas producers. Our Natural Gas Liquids segment’s customers also include NGL and natural gas gathering and processing companies. Our downstream commodity sales customers are primarily utilities, large industrial companies, natural gasoline distributors, propane distributors, municipalities and petrochemical, refining and marketing companies. Our Natural Gas Pipeline segment’s assets primarily serve local natural gas distribution companies, electric-generation facilities, large industrial companies, municipalities, producers, processors and marketing companies. Our utility customers generally require our services regardless of commodity prices. See discussion regarding our customer credit risk under “Counterparty Credit Risk” in Part II, Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Other

Through ONEOK Leasing Company, L.L.C. and ONEOK Parking Company, L.L.C., we own a 17-story office building (ONEOK Plaza) with 505,000 square feet of net rentable space and a parking garage in downtown Tulsa, Oklahoma, where our headquarters are located. ONEOK Leasing Company, L.L.C. leases excess office space to others and operates our headquarters office building. ONEOK Parking Company, L.L.C. owns and operates a parking garage adjacent to our headquarters.

REGULATORY, ENVIRONMENTAL AND SAFETY MATTERS

Environmental Matters - We are subject to a variety of historical preservation and environmental laws and/or regulations that affect many aspects of our present and future operations. Regulated activities include, but are not limited to, those involving air emissions, storm water and wastewater discharges, handling and disposal of solid and hazardous wastes, wetlands and waterways preservation, cultural resources protection, hazardous materials transportation, and pipeline and facility construction. These laws and regulations require us to obtain and/or comply with a wide variety of environmental clearances, registrations, licenses, permits and other approvals. Failure to comply with these laws, regulations, licenses and permits may expose us to fines, penalties and/or interruptions in our operations that could be material to our results of operations. For example, if a leak or spill of hazardous substances or petroleum products occurs from pipelines or facilities that we own, operate or otherwise use, we could be held jointly and severally liable for all resulting liabilities, including response, investigation and cleanup costs, which could affect materially our results of operations and cash flows. In addition, emissions controls and/or other regulatory or permitting mandates under the Clean Air Act and other similar federal and state laws could require unexpected capital expenditures at our facilities. We cannot assure that existing environmental statutes and regulations will not be revised or that new regulations will not be adopted or become applicable to us.

Some scientists have determined that GHG emissions endanger public health and the environment because emissions of such gases may contribute to warming of the earth’s atmosphere and other climatic changes. GHG emissions originate primarily from combustion engine exhaust, heater exhaust and fugitive methane gas emissions. International, federal, regional and/or state legislative and/or regulatory initiatives may attempt to control or limit GHG emissions, including initiatives directed at issues associated with climate change. Various federal and state legislative proposals have been introduced to regulate the emission of GHGs, particularly carbon dioxide and methane, and the United States Supreme Court has ruled that carbon dioxide is a pollutant subject to regulation by the EPA. In addition, there have been international efforts seeking legally binding reductions in emissions of GHGs.

Our environmental and climate change actions focus on minimizing the impact of our operations on the environment. These actions include: (i) developing and maintaining an accurate GHG emissions inventory according to current rules issued by the EPA; (ii) improving the efficiency of our various pipelines, natural gas processing facilities and natural gas liquids fractionation facilities; (iii) following developing technologies for emissions control and the capture of carbon dioxide to keep it from reaching the atmosphere; and (iv) utilizing practices to reduce the loss of methane from our facilities. In addition, many of our compressor station facilities are designed and operated with electric-driven compression units, which greatly reduce the potential emission from these facilities, including GHG emissions.

We participate in the EPA’s Natural Gas STAR Program to reduce voluntarily methane emissions. We continue to focus on maintaining low methane gas release rates through expanded implementation of best practices to limit the release of natural gas during pipeline and facility maintenance and operations.

We believe it is likely that future governmental legislation and/or regulation may require us either to limit GHG emissions from our operations or to purchase allowances for such emissions. However, we cannot predict precisely what form these future regulations will take, the stringency of the regulations or when they will become effective. In addition to activities on the federal level, state and regional initiatives could also lead to the regulation of GHG emissions sooner than and/or independent of federal regulation. These regulations could be more stringent than any federal legislation that may be adopted.

For additional information regarding the potential impact of laws and regulations on our operations see Item 1A “Risk Factors.”

Pipeline Safety - We are subject to PHMSA safety regulations, including pipeline asset integrity-management regulations. The Pipeline Safety Improvement Act of 2002 requires pipeline companies operating high-pressure pipelines to perform integrity assessments on pipeline segments that pass through densely populated areas or near specifically designated high-consequence areas. The Pipeline Safety, Regulatory Certainty and Job Creation Act of 2011 (the 2011 Pipeline Safety Act) increased maximum penalties for violating federal pipeline safety regulations, directs the DOT and Secretary of Transportation to conduct further review or studies on issues that may or may not be material to us and may result in the imposition of more stringent regulations.

Since 2015, PHMSA has issued notices of proposed rule-making for hazardous liquid pipeline safety regulations, natural gas transmission and gathering lines and underground natural gas storage facilities, none of which have become final. The potential capital and operating expenditures related to the proposed regulations are unknown, but we do not anticipate a material impact to our planned capital, operations and maintenance costs resulting from compliance with the current or pending regulations.

Air and Water Emissions - The Clean Air Act, the Clean Water Act, analogous state laws and/or regulations impose restrictions and controls regarding the discharge of pollutants into the air and water in the United States. Under the Clean Air Act, a federally enforceable operating permit is required for sources of significant air emissions. We may be required to incur certain capital expenditures for air pollution-control equipment in connection with obtaining or maintaining permits and approvals for sources of air emissions. The Clean Water Act imposes substantial potential liability for the removal of pollutants discharged to waters of the United States and remediation of waters affected by such discharge.

International, federal, regional and/or state legislative and/or regulatory initiatives may attempt to control or limit GHG emissions, including initiatives directed at issues associated with climate change. We monitor all relevant legislation and regulatory initiatives to assess the potential impact on our operations and otherwise take efforts to limit GHG emissions from our facilities, including methane. The EPA’s Mandatory Greenhouse Gas Reporting Rule requires annual GHG emissions reporting from affected facilities and the carbon dioxide emission equivalents for the natural gas delivered by us and the emission equivalents for all NGLs produced by us as if all of these products were combusted, even if they are used otherwise.

Our 2017 total emissions reported pursuant to EPA requirements were approximately 50 million metric tons of carbon dioxide equivalents. This total includes direct emissions from the combustion of fuel in our equipment, such as compressor engines and heaters, as well as carbon dioxide equivalents from natural gas and NGL products delivered to customers and produced as if all such fuel and NGL products were combusted. The additional cost to gather and report this emission data did not have, and we do not expect it to have, a material impact on our results of operations, financial position or cash flows. In addition, Congress has considered, and may consider in the future, legislation to reduce GHG emissions, including carbon dioxide and methane. Likewise, the EPA may institute additional regulatory rule-making associated with GHG emissions from the oil and natural gas industry. At this time, no rule or legislation has been enacted that assesses any costs, fees or expenses on any of these emissions.

We closely monitor proposed and final rule-makings. At this time we do not anticipate a material impact to our planned capital, operations and maintenance costs resulting from compliance with the current or pending regulations and EPA actions. However, the EPA may issue additional regulations, responses, amendments and/or policy guidance, which could alter our present expectations. Generally, EPA rule-makings require expenditures for updated emissions controls, monitoring and record-keeping requirements at affected facilities.

Chemical Site Security - The United States Department of Homeland Security (Homeland Security) released the Chemical Facility Anti-Terrorism Standards in 2007, and the new final rule associated with these regulations was issued in December 2014. We provided information regarding our chemicals via Top-Screens submitted to Homeland Security, and our facilities subsequently were assigned one of four risk-based tiers ranging from high (Tier 1) to low (Tier 4) risk, or not tiered at all due to low risk. To date, one of our facilities has been given a Tier 4 rating. Facilities receiving a Tier 4 rating are required to complete Site Security Plans and possible physical security enhancements. We do not expect the Site Security Plans and possible security enhancement costs to have a material impact on our results of operations, financial position or cash flows.

Pipeline Security - The United States Department of Homeland Security’s Transportation Security Administration and the DOT have completed a review and inspection of our “critical facilities” and identified no material security issues. Also, the Transportation Security Administration has released new pipeline security guidelines that include broader definitions for the determination of pipeline “critical facilities.” We have reviewed our pipeline facilities according to the new guideline requirements, and there have been no material changes required to date.

EMPLOYEES

At January 31, 2019, we employed 2,684 people.

EXECUTIVE OFFICERS

All executive officers are elected annually by our Board of Directors. Our executive officers listed below include the officers who have been designated by our Board of Directors as our Section 16 executive officers.

Name and Position		Age			Business Experience in Past Five Years
John W. Gibson		66			2011 to present		Chairman of the Board, ONEOK
Chairman of the Board					2007 to 2017		Chairman of the Board, ONEOK Partners
					2007 to 2014		Chief Executive Officer, ONEOK and ONEOK Partners
Terry K. Spencer		59			2014 to present		President and Chief Executive Officer, ONEOK
President and Chief Executive Officer					2014 to 2017		President and Chief Executive Officer, ONEOK Partners
					2014 to present		Member of the Board of Directors, ONEOK
					2014 to 2017		Member of the Board of Directors, ONEOK Partners
					2012 to 2014		President, ONEOK and ONEOK Partners
Robert F. Martinovich		61			2015 to present		Executive Vice President and Chief Administrative Officer, ONEOK
Executive Vice President and Chief Administrative Officer					2015 to 2017		Executive Vice President and Chief Administrative Officer, ONEOK Partners
					2014 to 2015		Executive Vice President, Commercial, ONEOK and ONEOK Partners
					2013 to 2014		Executive Vice President, Operations, ONEOK and ONEOK Partners
Walter S. Hulse III		55			2017 to present		Chief Financial Officer and Executive Vice President, Strategic Planning and Corporate Affairs, ONEOK
Chief Financial Officer, Executive Vice President, Strategic Planning and Corporate Affairs					2015 to 2017		Executive Vice President, Strategic Planning and Corporate Affairs, ONEOK and ONEOK Partners
					2012 to 2015		Managing Member, Spinnaker Strategic Advisory Services, LLC
Kevin L. Burdick		54			2017 to present		Executive Vice President and Chief Operating Officer, ONEOK
Executive Vice President and Chief Operating Officer					2017		Executive Vice President and Chief Commercial Officer, ONEOK and ONEOK Partners
					2016 to 2017		Senior Vice President, Natural Gas Gathering and Processing, ONEOK Partners
					2013 to 2016		Vice President, Natural Gas Gathering and Processing, ONEOK Partners
Wesley J. Christensen		65			2014 to present		Senior Vice President, Operations, ONEOK
Senior Vice President, Operations					2011 to 2017		Senior Vice President, Operations, ONEOK Partners
Charles M. Kelley		60			2018 to present		Senior Vice President, Natural Gas, ONEOK
Senior Vice President, Natural Gas					2017 to 2018		Senior Vice President, Natural Gas Gathering & Processing, ONEOK
					2015 to 2017		Senior Vice President, Corporate Planning and Development, ONEOK and ONEOK Partners
					2014 to 2015		Vice President, Corporate Development, ONEOK and ONEOK Partners
					2008 to 2014		Senior Vice President, Energy Services, ONEOK
Sheridan C. Swords		49			2013 to present		Senior Vice President, Natural Gas Liquids, ONEOK
Senior Vice President, Natural Gas Liquids					2013 to 2017		Senior Vice President, Natural Gas Liquids, ONEOK Partners
Derek S. Reiners		47			2017 to present		Senior Vice President, Finance and Treasurer, ONEOK
Senior Vice President, Finance and Treasurer					2013 to 2017		Senior Vice President, Chief Financial Officer and Treasurer, ONEOK and ONEOK Partners
Stephen B. Allen		45			2017 to present		Senior Vice President, General Counsel and Assistant Secretary, ONEOK
Senior Vice President, General Counsel and Assistant Secretary					2008 to 2017		Vice President and Associate General Counsel, ONEOK and ONEOK Partners
Sheppard F. Miers III		50			2013 to present		Vice President and Chief Accounting Officer, ONEOK
Vice President and Chief Accounting Officer					2013 to 2017		Vice President and Chief Accounting Officer, ONEOK Partners

No family relationships exist between any of the executive officers, nor is there any arrangement or understanding between any executive officer and any other person pursuant to which the officer was selected.

INFORMATION AVAILABLE ON OUR WEBSITE

We make available, free of charge, on our website (www.oneok.com) copies of our Annual Reports, Quarterly Reports, Current Reports on Form 8-K, amendments to those reports filed or furnished to the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act and reports of holdings of our securities filed by our officers and directors under Section 16 of the Exchange Act as soon as reasonably practicable after filing such material electronically or otherwise furnishing it to the SEC. Copies of our Code of Business Conduct and Ethics, Corporate Governance Guidelines, Director Independence Guidelines, Bylaws and the written charter of our Audit Committee also are available on our website, and we will provide copies of these documents upon request.

In addition to our filings with the SEC and materials posted on our website, we also use social media platforms as additional channels of distribution to reach public investors. Information contained on our website, posted on our social media accounts, and any corresponding applications, are not incorporated by reference into this report.