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Breaking down the utility charges on your residential bill - Ameren Illinois

For ease of comparison, we list the Price to Compare before we break down the charges on your utility bill. Items A, B and C below reflect the order in which they appear on your Ameren Illinois bill. When you select service from a retail electric supplier, the Ameren Illinois Electric Supply and Transmission Services Charge (items B and C below) will be replaced with the charges from your new retail electric supplier. Currently, most suppliers will place their charges on your Ameren Illinois bill and some suppliers will send you a bill directly (containing Ameren Illinois delivery service charges as well as the supplier's supply and transmission charges).

Price to Compare = Electric Supply Charges + Transmission Service Charge

Historical Prices to Compare

Combining the electric supply charges and the transmission service charge results in the current Ameren Illinois Price to Compare, which is effective June 1, 2022 through September 30, 2022.

Price to Compare (in cents per kWh)

Summer (June 1, 2022 - September 30, 2022)
10.628 cents per kWh

A. Delivery Service Charges

You will pay the charges to deliver the electric supply from the transmission system to your home regardless of whether you purchase your electric supply from Ameren Illinois or a Retail Electric Supplier. On your Ameren Illinois bill, these charges are listed as DS or Delivery Service charges.

B. Electric Supply Charges

The electric supply charge is the price you pay per kWh for the amount of electricity you use in your home. The price of electric supply is determined by your choice of supplier, whether it be a Retail Electric Supplier or the electric utility. The Ameren Illinois rate for the electric supply during the summer months (June through September) is different from the utility rate during the non-summer months (October through May).

Summer (June 1, 2022 - September 30, 2022)
8.765 cents per kWh

Over the course of a year, your average utility rate per kWh is likely somewhere between the summer rate and the non-summer rate. Whether your average electricity supply charge for a 12-month period is closer to the summer rate or closer to the non-summer rate depends on how much electricity you use and during which months you use it. Please take a look at your electric bill or log in to your Ameren Illinois account here to see how much electricity you typically use over the course of a year and when you use it.

The Electric Supply charge section on your Ameren Illinois bill includes a “Supply Cost Adjustment.” The Supply Cost Adjustment is designed to allow the utility to recover costs associated with procurement, working capital and uncollectible charges. The Supply Cost Adjustment is largely a fixed charge that changes only when the ICC makes changes to Ameren Illinois' delivery service rates, after an annual power supply procurement update, or pursuant to other Commission Orders. The currently effective fixed Supply Cost Adjustment is 0.227 cents per kWh for all Ameren Illinois Rate Zones. When calculating the utility's electric supply price for Ameren Illinois' Price to Compare, we do include the Supply Cost Adjustment.

You will also notice on your bill a monthly "Purchased Electricity Adjustment" that causes the electric supply charges to fluctuate above or below the established electric supply rate from one month to the next. The purpose of the Purchased Electric Adjustment is to "true-up" any difference (over or under) between what Ameren Illinois previously paid to acquire electric supply and what Ameren Illinois previously charged its customers for that electric supply. Ameren Illinois expects the Purchased Electricity Adjustment to be close to zero for the foreseeable future. When calculating the utility's electric supply price for Ameren Illinois Price to Compare, we do not include a value for the Purchased Electricity Adjustment. You will not be subject to the Purchased Electric Adjustment when you switch to a Retail Electric Supplier.

Attention Residential Real Time Pricing (RRTP) Customers

To make a meaningful comparison between variable Power Smart Pricing rates and RES offers, customers should compare their past supply cost savings, provided by their Power Smart Pricing provider, with a supply cost savings estimate provided by RESs. Competitive supplier savings estimates are often calculated on a percentage savings compared to the utility's Price to Compare. Alternatively, customers can compute their average real-time price in cents per kWh to compare with RES offers posted in cents per kWh. Customer should bear in mind, however, that since Power Smart Pricing rates vary over time, past savings do not predict future savings, but only serve as a guide to compare past performance.

C. Transmission Service Charge

Also included in the Electric Supply Section on your Ameren Illinois bill is the Transmission Service Charge. The transmission service charge is designed to allow the utility to recover costs associated with transmission service. The transmission charge is set annually by the Federal Energy Regulatory Commission (FERC). Ameren Illinois determines its transmission charge annually for prices effective each June through the following May.

The currently effective transmission service charge that we include in the Ameren Illinois Price to Compare is 1.62 cents per kWh for Ameren Illinois Non-Interval Metered customers.