What we cover
This page is generated from the same registry the engine reads, so it cannot describe coverage the product does not have. A rate class is only marked supported when a deterministic tariff implementation exists, it is validated against real bills for the periods claimed, its fixtures pass in CI, and the charges that carry a bill are filed for the dates being priced.
National Grid · SC-1 — Residential and Farm Service
Niagara Mohawk Power Corporation · P.S.C. No. 220 — Electricity
Validated against four real bills. Three price and every total lands within three cents of the printed bill. The fourth is refused: two merchant-function factors are not on file for that period, and a total missing them would be wrong rather than merely incomplete. Rates are cross-checked against Arcadia's independently maintained model of the same tariff, which confirms them to the digit. Six lines across the three bills differ by two to six cents, so a line-by-line comparison is not exact even though every total is. The rates themselves are not in doubt — the filed surcharge is the tax rate over one minus itself, which is why 3% appears as 3.09278% — and the residue is in how a line built from several filed components is rounded.
Priceable from 2026-03-25 onward. Earlier periods are refused rather than estimated.
National Grid · SC-2D — Small General Service — Demand Metered
Niagara Mohawk Power Corporation · P.S.C. No. 220 — Electricity
Demand-metered commercial, validated against fourteen consecutive real bills. All fourteen price; ten land within five dollars of the printed delivery total and three land exactly. Three differ for reasons we can name — one charges a surcharge National Grid filed in February 2025 and did not bill until July, two need a demand rate from before July 2025 that is published nowhere. Seven bills still differ by amounts we have not explained, all of them under a percent of the bill — and a second account has since shown that phrase was flattered by a small one. Eight bills from a commercial account using ten times the electricity differ by up to sixty-nine dollars on the delivery total. The cause is dated rate data, not arithmetic: the System Benefits Charge fell from $0.007487 to $0.003274 per kWh during July 2025 and only the later value is held, so any period before August 2025 is under-priced by an amount that scales with usage. Five of the eight delivery lines on that bill still match to the cent. Supply is not reconciled and cannot be: National Grid sets it as a 30-day load-shape average of hourly market prices, so it is read from the bill rather than recomputed. The delivery side is the part we check.
Priceable from 2025-05-23 onward. Earlier periods are refused rather than estimated.
National Grid · SC-2ND — Small General Service — Non-Demand
Niagara Mohawk Power Corporation · P.S.C. No. 220 — Electricity
Small general service without a demand meter. Every component is filed and priceable from April 2026, when its current tariff leaf took effect; nothing earlier is claimed, because National Grid publishes no superseded leaf and we hold no bills on this class to derive one from. Unlike SC-2D, its supply cost and reconciliation ARE published, by NYISO zone, in the monthly statements. Not validated against a real bill: we have none. Held mainly to answer whether a demand-metered customer would be better off here, which for the shop in evidence they would not.
Priceable from 2026-04-01 onward. Earlier periods are refused rather than estimated.
Con Edison · all — 81 rate plans (11 residential)
Tariff structure and monthly rate history are held, sourced from Arcadia's model. Nothing is validated against a real bill from this utility, so bills are read and explained but not reconciled to a filed rate.
No period can be priced from a filed rate yet.
PSEG Long Island · all — 53 rate plans (35 residential)
Tariff structure and monthly rate history are held, sourced from Arcadia's model. Nothing is validated against a real bill from this utility, so bills are read and explained but not reconciled to a filed rate.
No period can be priced from a filed rate yet.
NYSEG · all — 28 rate plans (7 residential)
Tariff structure and monthly rate history are held, sourced from Arcadia's model. Nothing is validated against a real bill from this utility, so bills are read and explained but not reconciled to a filed rate.
No period can be priced from a filed rate yet.
Central Hudson · all — 28 rate plans (7 residential)
Tariff structure and monthly rate history are held, sourced from Arcadia's model. Nothing is validated against a real bill from this utility, so bills are read and explained but not reconciled to a filed rate.
No period can be priced from a filed rate yet.
RG&E · all — 20 rate plans (5 residential)
Tariff structure and monthly rate history are held, sourced from Arcadia's model. Nothing is validated against a real bill from this utility, so bills are read and explained but not reconciled to a filed rate.
No period can be priced from a filed rate yet.
Any other utility · —
Upload a bill and we will read it, lay out what each line is, and check the arithmetic on the bill against itself. We will not claim to have checked it against a filed rate, because we do not hold one.
No period can be priced from a filed rate yet.
What “upload and review” means
We read the bill, lay out what each line is, and check the bill’s arithmetic against itself — that the meter reads produce the stated usage, that each charge equals its own printed rate times its own printed quantity, and that the lines sum to the total. What we do not do is compare it to a filed tariff, because we do not hold one for that utility. We will not describe that as an audit.