Item 1A. RISK FACTORS.

The Form 10-K includes a detailed discussion of our risk factors. The information presented below updates, and should be read in conjunction with, the risk factors and information disclosed in the Form 10-K.

The COVID-19 vaccine mandate issued under an executive order may have a material adverse effect on our results of operations, financial position, or liquidity.

In September 2021, President Biden issued an executive order directing that federal agencies require employers with United States government contracts to ensure that their United States-based employees, contractors, and subcontractors, at on-site and remote locations, are fully vaccinated for COVID-19, subject to certain exceptions for valid medical and religious reasons, as identified in applicable guidance. Without further change, the expected deadline for compliance is January 4, 2022. The executive order does not provide an exception for regular COVID-19 testing as an alternative to vaccination. As a United States government contractor, the Ameren Companies will be required to comply with the executive order’s vaccine mandate.

The timing of implementation of the executive order may be affected by additional guidance issued, including any extensions of time granted to comply. Compliance with the executive order or any future vaccine mandates may result in labor shortages, including shortages in skilled professional and technical labor, supply chain disruptions, delays in contractors’ performance or completion of work, and/or increased costs for us, our contractors, or our suppliers, which may have a material adverse effect on our results of operations, financial position, and liquidity.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS.

Ameren Corporation, Ameren Missouri, and Ameren Illinois did not purchase equity securities reportable under Item 703 of Regulation

S-K during the period from July 1, 2021, to September 30, 2021.