rates / Ameren Illinois Company

Ameren Illinois Company

Rate DS-1 Residential Delivery Service, bundled with Rider BGS-1 supply and Rider TS transmission

0.12122–0.20512$/kWh

by season and by usage tier · plus $13.28 per month · covers the full bill — everything the utility bills for energy - directly comparable to another bundled rate

Monthly bill

Usage	January to May and October to December	June to September
500 kWh	$94.02	$115.84
1,000 kWh	$166.70	$218.40
2,000 kWh	$287.92	$423.52

Computed from the rates on this page at 30.4 days a month. The same arithmetic is checked against the utility's own published typical bill on every build. Before taxes, franchise fees and any local surcharge.

Provenance

Confidence

• verifiedTranscribed from the utility's filed sheetIll. C.C. No. 1, 1st Revised Sheet No. 11 (Rate DS-1) with its charges in the Appendix of Rate PBR-R, 6th Revised Sheet No. 8.011, filed 21 August 2025 pursuant to ICC Order in Docket No. 25-0083
• verifiedEffective date on the sheet: 2026-10-01
• verifiedReconciles to a total the utility published itselfThe ICC's published Price to Compare for June 1 - September 30 2026, 11.326 cents/kWh. PTC is defined as supply + supply cost adjustment + transmission, and Ameren's filed 8.200 + 0.308 + 0.053 with the ICC's 2.765 trans
• verifiedRead twice, from independent sourcesThe delivery figures exist only as an image, so they were read a second time from the Citizens Utility Board's 2026 rate guide, which states it read the tariffs. All six 2026 figures and all six 2025 figures agree exactl
• verifiedSource document checked daily for changes
• excludedTaxes, franchise fees and local surchargesJurisdiction-specific, so they are deliberately not encoded. A bill will be higher than this figure by that amount.

Energy rates

Period	Applies to	$/kWh
June to September	all usage	$0.20512
January to May and October to December — tier 1	up to 800 kWh	$0.16147
January to May and October to December — tier 2	above 800 kWh	$0.12122

What this figure does and does not include

Transcription notes recorded when this tariff was encoded, including anything deliberately left out.

• THE DEFAULT RESIDENTIAL RATE in Ameren Illinois' territory, bundled with Rider BGS-1 default supply. Seasonal, and NOT time-of-use. ComEd is encoded the same way.
• THE DELIVERY CHARGES EXIST ONLY AS A PICTURE. Rate DS-1 is a pointer sheet with no numbers; the Rate PBR-R Appendix holds them, and its tables are images pasted into Word. Nothing extracts. The figures here were read off the image and then read a SECOND time from the Citizens Utility Board's independent 2026 guide - twelve figures across two years, all agreeing. That second reading is the only check that exists; do not overrule it without a third source.
• RATE MAP-P IS A SUPERSEDED REGIME, NOT A STALE SHEET. aiifmapp123.ashx gives DS-1 in clean text at customer $5.57 and summer $0.06008, dated January 2023, under the Modernization Action Plan formula that CEJA replaced with Performance-Based Ratemaking. The informational series ends at 123 because the regime ended. Right utility, right rate class, real text, plausible numbers - only the date and the regime name give it away.
• BOTH TIER BOUNDARIES ARE 800 kWh. Delivery and supply tier at the same point in non-summer and are both flat in summer, which is what makes one bundled block structure correct. If they ever diverge, this encoding is wrong.
• THE SUPPLEMENTAL CUSTOMER CHARGES ARE A NET CREDIT of $-0.10. Sheet No. 38 defines exactly four, billed as one line combined with the Customer Charge, and the UCB/POR Program Charge among them is ($0.99) for the April to December 2026 billing periods and $0.00 for January to March. A 'charge' here can be negative, and the tariff prints no total.
• THE $0.52 UNCOLLECTIBLE IS NOT BILLED. The Appendix lists it, but DS-1 puts it under Terms and Conditions as the amount 'recovered in base rates' pursuant to ICC Order in Docket No. 09-0399, which exists so Rider EUA recovers only the shortfall. Adding it would double-count. This is the least certain call here and it is worth $6.24 a year.
• TWO AMEREN SHEETS DISAGREE ABOUT THE EUA SUPPLY COST ADJUSTMENT. The annual filing prints (0.099); the monthly HSS/PER sheet prints 0.053. The annual sheet's own footnote defers to the monthly one, and only 0.053 reconciles to the ICC's Price to Compare. The annual figure would miss by 0.152 cents/kWh and nothing would look wrong.
• THE PURCHASED ELECTRICITY ADJUSTMENT IS EXCLUDED, as it is from the ICC's own Price to Compare. It is -0.00055/kWh this month, is a true-up that changes every billing cycle, and the ICC states Ameren expects it near zero.
• RATE ZONE I IS ENCODED. Rider EEA differs by zone - 0.00987 cents in Zone I and 0.00711 in Zone III for September 2026 - and Rider HMAC applies only in Zone III, at zero. The gap is 0.00267 cents/kWh, about three cents a year at 12,000 kWh, so no territory table is built for it.
• SHELVE WHAT HAS A PERIOD, DISCLOSE WHAT HAS A CADENCE. Rider CSESC is filed QUARTERLY and its October-December 2026 period is $0.00008/kWh, down from $0.00009 since April - about twelve cents a year at 12,000 kWh. That has a start and an end, so it is encoded as its own vintage. Rider EEA changes EVERY MONTH and has no next value until Ameren files one, so no vintage is created for it alone; each vintage carries the EEA of the month it is dated for and the source is watched daily. The October vintage's EEA, 0.00985 cents, is right for October and will drift in November by about two hundredths of a cent a year, which is disclosed rather than chased.
• TRANSMISSION IS THE ICC'S FIGURE, NOT AMEREN'S. Rider TS says a Transmission Service Charge informational sheet is filed, but Ameren's residential rates index does not carry one. The 2.765 cents/kWh here is published by the ICC on plugin.illinois.gov and is watched there.
• SEASONS ARE DEFINED IN THE CUSTOMER TERMS AND CONDITIONS, not in DS-1: Summer is June, July, August and September; Non-Summer is the other eight months. Delivery and supply use the same definition.
• SEVEN NAMED RIDERS ARE ABSENT ON PURPOSE, having been checked rather than skipped: HMAC (Zone III only, 0.00000), EDR (0.000, superseded by Rider EE), EF and IMF and GC (named municipalities only), PTR (an optional credit programme), and Tax Additions (jurisdiction-specific, as everywhere else here).
• NOT ENCODED: Rider RTP real-time pricing, Power Smart Pricing as a supply option, Rider EVCP for electric vehicles, and the Delivery-Time-of-Use pilot.

Think a figure here is wrong?

Email support@rategrid.dev with this plan's name and what the filed sheet says. Every rate on this page was transcribed from the document linked above, so a report that quotes the sheet can be checked against it and corrected.

Change history

The source document is fetched daily and every version is kept. Utilities do not publish superseded rates, so this record does not exist elsewhere once a rate changes.

No changes detected since monitoring began. The source sheet is checked daily.

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Estimates only. Excludes taxes, franchise fees, medical baseline, FERA and annual true-up. Not a bill.