Electricity rates — Ameren Illinois Company
A household served by Ameren Illinois Company using 1,000 kWh a month pays about $2,743.60 a year on the cheapest of 2 generally available plans — DS-1 Residential Zone 2 from Ameren Illinois Company, in effect since March 2026. Rates checked September 23, 2026. A further 2 restricted and 1 older schedules are priced further down but not ranked.
Every priced plan, 1,000 kWh/mo
| Plan | Per year | vs cheapest | Effective |
|---|---|---|---|
| DS-1priced by season · no start date · older schedule, not ranked | $358.66 | −$2,384.94 | 3.0¢ |
| DS-1 Residential Zone 1priced by season · tiered · in effect since March 2026 · delivery charges only | $2,280.08 | −$463.52 | 19.0¢ |
| DS-1 Residential Zone 3priced by season · tiered · in effect since March 2026 · delivery charges only | $2,344.64 | −$398.96 | 19.5¢ |
| DS-1 Residential Zone 2✓ cheapestpriced by season · tiered · in effect since March 2026 | $2,743.60 | — | 22.9¢ |
| DS-1 Residential Zone 3priced by season · tiered · in effect since March 2026 | $5,616.04 | +$2,872.44 | 46.8¢ |
Cost across usage levels
The cheapest plan at each consumption level, showing whether the ranking holds as usage changes.
- 500 kWh/mo — cheapest $1,480.32 (DS-1 Residential Zone 2), dearest $2,916.56, a $1,436.24 spread
- 1,000 kWh/mo — cheapest $2,743.60 (DS-1 Residential Zone 2), dearest $5,616.04, a $2,872.44 spread
- 2,000 kWh/mo — cheapest $5,122.96 (DS-1 Residential Zone 2), dearest $10,867.88, a $5,744.92 spread
What a typical bill costs
At 1,000 kWh a month the 2 generally available plans here run from $2,743.60 on DS-1 Residential Zone 2 to $5,616.04 on DS-1 Residential Zone 3, with a median of $4,179.82.
Effective rates, bill divided by kilowatt-hours, span 22.9¢ to 46.8¢ per kWh at that usage.
What Ameren Illinois Company's customers were billed in 2024
Ameren Illinois Company's open plans and its customers' bills disagree by more than a quarter: at 853 kWh a month, the median plan is 35.4¢ per kWh against 15.3¢ billed in 2024. Before relying on a plan price here, test it against a real Ameren Illinois Company bill in the bill analyzer.
| Ownership, as EIA classes it | Investor-owned |
|---|---|
| Full-service homes in Illinois | 520,498 |
| Homes it delivers to for other suppliers | 540,396 |
| Share of Illinois's households | 20% |
| Average use per home | 853 kWh a month |
| Average bill per home | $130.20 a month |
| Billed per kWh, riders included | 15.3¢ |
| Median open plan here, at that use | 35.4¢ |
Ameren Illinois Company in U.S. Energy Information Administration, Form EIA-861, 2024 (Sales_Ult_Cust_2024.xlsx), retrieved September 23, 2026.
How it compares
Among the 109 utilities indexed, Ameren Illinois Company's cheapest open plan is the 15th-highest, 66% more than their median of $1,649.16. It sits between PECO Energy Co ($2,723.54) and Baltimore Gas & Electric Co ($2,776.94).
In Illinois it is the dearest of the 2 utilities indexed; Commonwealth Edison Co starts lowest, at $1,750.64.
DS-1 Residential Zone 3 is tiered: past 800 kWh a month, each kWh costs 3.1¢ less. Of the 51 utilities whose plans step, that is the 16th-largest step.
DS-1 Residential Zone 3 changes price with the season: a kWh costs 67.6¢ more in June to September than in October to May, and the same 1,000 kWh is billed $922.83 in its dearest month against $240.59 in its cheapest.
In the guides: The price that changes once the meter passes a line · The price that changes with the month
How the answer changes with usage
DS-1 Residential Zone 2 is cheapest at every level tested — $1,480.32 a year at 500 kWh a month, $5,122.96 at 2,000 kWh.
The penalty for a poor choice grows with usage: $1,436.24 a year at 500 kWh against $5,744.92 at 2,000 kWh.
Cheapest 5 plans at 1,000 kWh a month
DS-1 — $358.66 a year, 3.0¢ per kWh effective, priced by season. It carries no standing charge. It states no start date. Too old to quote as a current price.
DS-1 Residential Zone 1 — $2,280.08 a year, 19.0¢ per kWh effective, tiered and priced by season. It carries a $14.01 monthly standing charge. In effect since March 2026. Restricted: delivery charges only.
DS-1 Residential Zone 3 — $2,344.64 a year, 19.5¢ per kWh effective, tiered and priced by season. It carries a $14.01 monthly standing charge. In effect since March 2026. Restricted: delivery charges only.
DS-1 Residential Zone 2 — $2,743.60 a year, 22.9¢ per kWh effective, tiered and priced by season. It carries a $14.01 monthly standing charge. In effect since March 2026.
DS-1 Residential Zone 3 — $5,616.04 a year, 46.8¢ per kWh effective, tiered and priced by season. It carries a $14.01 monthly standing charge. In effect since March 2026.
How these plans are structured
Of 5 priceable plans: 4 tiered, 5 priced by season.
Every plan carries a $14.01 fixed monthly charge.
Who provides these plans
EIA-861 lists Ameren Illinois Company serving homes in Illinois and in no other state, which is how its plans are placed there. 5 of its 5 published residential schedules can be priced.
The largest saving available here
Moving from DS-1 Residential Zone 3 to DS-1 Residential Zone 2 saves $2,872.44 a year at 1,000 kWh a month, with no change in consumption.
New to these terms? The methodology page explains tiered bands, time-of-use periods and fixed charges, and sets out exactly what the rate engine assumes.
Estimate — your actual bill may differ.
Tariff structures from NREL/OpenEI Utility Rate Database (CC0 1.0), retrieved September 23, 2026.