What is a kilowatt-hour (kWh)?

The short answer

A kilowatt-hour is a unit of energy: one kilowatt of power, which is 1,000 watts, used for one hour. EIA's Energy Explained page on measuring electricity defines it the same way: "one kWh is one kilowatt generated for one hour". A 100-watt bulb left on for 10 hours uses one kWh; so does a heater drawing 1,000 watts for one hour, or a 50-watt device running for 20 hours.

The kWh matters because it is what the meter counts and what most of a residential bill is priced on. The why is my electric bill so high guide uses it to diagnose a bill; this page explains the unit itself and what one of them costs across the country.

Kilowatts measure power, kilowatt-hours measure energy

The two are easy to confuse because they share a name. A kilowatt (kW) is a rate: how much power a device draws at one moment, the way speed is a rate. A kilowatt-hour is a quantity: how much energy was used over a period, the way distance is speed times time. A space heater rated at one kilowatt uses half a kWh in 30 minutes and two kWh in two hours.

Residential bills charge for kWh. Many commercial and industrial tariffs also charge for kW, the highest rate of draw in the billing period; that is a separate line called a demand charge, explained in the demand charges guide. A watt-hour is a thousandth of a kWh, the unit printed on small appliance labels and phone batteries.

What one kWh costs in the US

EIA does not publish one national price per kWh. It publishes average revenue per kWh: what customers paid in total divided by the kWh they bought. That figure includes fixed monthly charges, fuel adjustments and riders, excludes most taxes, and is not anyone's tariff.

The 12-month figure is the best single answer to "how much is a kWh": it averages out the season. The single month reads differently because the mix of customers and the share of fixed charges change from month to month. Over the last 12 months the residential average per kWh was highest in April 2026 (18.86¢ per kWh) and lowest in December 2025 (17.11¢ per kWh¹). Mild months carry a fixed customer charge over fewer kWh, which lifts the average per kWh even when the tariff has not changed.

The Bureau of Labor Statistics measures the same thing another way. Its average price for the U.S. city average was $0.190 per kWh³ in October 2026, quoted in dollars rather than cents, collected in urban areas and including taxes and fixed charges as billed. Neither number is wrong; they cover different customers and charges, so compare a figure only with others of its own kind.

Looking ahead, EIA's November 2026 Short-Term Energy Outlook forecasts a residential average of 18.17¢ per kWh for 2026 (partly estimated) and 18.68¢ per kWh⁴ for 2027. These are forecasts, not measured prices.

The same kWh at very different prices

The price of a kWh depends heavily on where it is bought. Over the last 12 months (September 2025 to August 2026), residential customers paid an average of 44.27¢ per kWh in Hawaii and 12.35¢ per kWh in North Dakota. In 15¹ of the 50 states and DC the average was 20¢ or more.

The US average sits above most states. Only 18 of the 50 states and DC paid more than the national 18.04¢ per kWh over the same 12 months, and the median state paid 15.77¢ per kWh. The national figure weights each state by its kWh sold, so large high-priced states such as California¹ pull it up. A "national average" quoted for your own home will usually be off in one direction or the other; your state's page gives the local average.

Who owns the utility also lines up with the price. In 2025, residential customers of investor-owned utilities paid an average of 17.78¢ per kWh, against 14.49¢ per kWh for public power and 14.10¢ per kWh for electric cooperatives (bundled full-service customers). Among utilities with 100,000 or more residential customers, averages ran from 10.51¢ per kWh at Magic Valley Electric Cooperative (Texas) to 45.77¢ per kWh at SDG&E (California)⁶.

Investor-owned utilities17.78¢

Electric cooperatives14.10¢

Public power (municipal, districts, state)14.49¢

Source: EIA-861 annual electric power industry report, 2025 final. Bundled (full-service) residential revenue divided by kWh, summed over every utility of each type (EIA-861 2025). Small utilities filing the short form report no residential split and are not included.

Show the numbers

Type	¢/kWh	Residential customers
Investor-owned utilities	17.78¢	81,897,613
Electric cooperatives	14.10¢	18,637,750
Public power (municipal, districts, state)	14.49¢	18,508,158

Homes pay more per kWh than factories

The price of a kWh also depends on who buys it. Over the last 12 months the US average was 18.04¢ per kWh for residential customers, 13.87¢ per kWh for commercial customers and 8.91¢ per kWh for industrial customers (September 2025 to August 2026). EIA's explainer on electricity prices gives the reason: industrial consumers use more electricity and can receive it at higher voltages, while it costs more to distribute electricity to homes and businesses. This is why an "electricity price" quoted without the sector, such as the all-sector average of 14.15¢ per kWh¹, understates what a household pays.

Residential18.04¢

Commercial13.87¢

Industrial8.91¢

All sectors14.15¢

Source: EIA, Electric Power Monthly / EIA-861M sales and revenue by state. Average revenue per kWh: what each customer class paid in total divided by what it used. Industrial customers take power at higher voltage and in large, steady volumes, so their average is lower. Monthly EIA data through August 2026 (released October 23, 2026); months since January 2026 are preliminary.

Show the numbers

Sector	United States (¢/kWh)
Residential	18.04¢
Commercial	13.87¢
Industrial	8.91¢
All sectors	14.15¢

How many kWh a home uses

The average US residential customer used 874 kWh⁷ a month in 2025, according to EIA's annual survey of utilities, and 875 kWh¹ a month over the last 12 months (September 2025 to August 2026). EIA's household survey put annual use at 10,580 kWh a year⁸ in 2020, a pandemic year with more time at home; its 2024 figures are due in spring 2027.

Use is not steady. In the last 12 months US use per home ran from 678 kWh in April 2026 to 1,160 kWh in July 2026, a peak 1.7 times¹ the low. Air conditioning drives the summer peak in most of the country and electric heating the winter one.

Worked example: why the price per kWh is not the bill

A monthly bill is roughly the kWh used times the average price per kWh. The two pull in different directions across states, so the most expensive kWh does not always mean the most expensive bill.

In 2025, Hawaii homes paid an average of 40.40¢ per kWh, several times the 11.82¢ per kWh paid in North Dakota. But the average Hawaii home used 515 kWh a month against 1,070 kWh in North Dakota. The result: an average bill of $207.89 in Hawaii and $126.40 in North Dakota, a gap far smaller than the gap in price. California and Louisiana show the same effect: California averaged 31.35¢ per kWh on 494 kWh a month, Louisiana 12.52¢ per kWh² on 1,225 kWh, and their average bills ended close together ($154.73 and $153.32⁷).

To make the same calculation for your home, take the kWh from your bill and the 12-month average for your state or utility; the bill calculator does it with EIA's averages preloaded, and the electricity cost guide covers appliances.

Where your kWh are counted

The meter at your home records cumulative kWh; the bill shows the difference between two readings. Most meters now report readings to the utility automatically. In 2025, advanced two-way meters made up 91.6% of residential meters in the median state, according to EIA-861. Those meters record kWh by hour, which is what makes time-of-use pricing possible: a kWh used at the evening peak can cost more than one used overnight. 11.3%⁹ of US residential customers were on a time-varying rate in 2025; see time-of-use rates.

On the bill itself, look for three things: the kWh for the billing period, the number of days it covers, and charges listed "per kWh" separately from the fixed monthly charge. Some bills split the per-kWh price into a supply part and a delivery part; the delivery vs supply guide explains the split.

Bigger units: MWh, GWh and TWh

Utilities and power plants work in larger multiples of the same unit. A megawatt-hour (MWh) is 1,000 kWh, the unit of most wholesale power prices. A gigawatt-hour is a million kWh and a terawatt-hour a billion. US power plants generated 4,425.0 terawatt-hours¹⁰ in 2025. For scale, EIA counted 144,800,940² residential customer accounts that year, each using an average of 874 kWh⁷ a month.