Why a bill differs from the rate schedule

A rate schedule, or tariff, is the legal price list a utility bills from. The average price on this site is what came out of all those bills, divided by the kilowatthours sold. The two seldom match, for reasons that are worth separating.

Fixed charges

Most residential schedules have a monthly customer charge that is owed whatever the use. It raises the cost per kilowatthour for a household that uses little and barely registers for one that uses a lot.

Tiers and seasons

Some schedules charge more per kilowatthour above a monthly threshold (inclining blocks), a few charge less (declining blocks), and many have different summer and winter rates. A household's average cost per kilowatthour then depends on the month and on where its use falls against the thresholds.

Time of use and demand

Time-of-use schedules price a kilowatthour by the hour it is used. A small number of residential schedules, and most commercial ones, also charge for the highest demand in the month. Two households with the same monthly kilowatthours can owe different amounts.

Riders and adjustments

The energy rate printed on a schedule is usually joined by separate lines: fuel or purchased-power adjustments that move with wholesale costs, storm-recovery charges, efficiency and renewable programme charges, transmission charges. They are set in separate proceedings and can change more often than the base rate.

Taxes and fees

Local franchise fees, state taxes and municipal surcharges appear on bills and differ from town to town within one utility's territory.

How much power a home uses

Consumption moves bills more than any of the above. Average residential use in 2024 ran from 495 kWh a month in Hawaii to 1,202 kWh in Louisiana, against a US average of 863 kWh. Electric heating, air conditioning, water heating and home size account for most of the spread. Louisiana's average price was 11.73¢ and its average bill $140.96; Hawaii's price was 42.86¢ and its bill $212.12.

What the average does and does not cover

EIA's average price folds all of this into one number per utility, sector and year. It is a sound basis for comparing utilities and tracking change over time. It is not a quote. The tariff book filed with the state utility commission, or published by a municipal or cooperative utility's board, is the source for the schedule a household is billed under.