Supply vs. Delivery Charges: The Two Halves of Your Electric Bill

Two halves of one bill

Think of an electric bill like a pizza order. Supply is the pizza: the electricity generated at a power plant or bought on the wholesale market. Delivery is the car and the driver: the high-voltage transmission lines, the local distribution poles and wires, the substations and transformers, and the meter on your wall.

Some bills show these as two clearly separate sections. Others, especially from utilities that own their power plants, blend them into one energy charge plus a few extra lines. Either way, both costs are in there. You can find the definitions in our glossary under supply charge and delivery charge.

Which half is bigger?

It depends on where you live and how your bill is set up. Nationally, across all customer types, EIA estimates that in 2025 generation made up about 56% of the average price of electricity, distribution about 30% and transmission about 14%^[1]. EIA describes generation as the largest component of the price.

Home customers, though, are served at lower voltage and tend to bear more of the local distribution cost than large industrial users. A clean national look at households comes from EIA's utility data: in 2025, about 14.6 million residential customers bought their energy from a supplier other than their utility and paid the utility separately for delivery. For that group, energy supply averaged about 12.3 cents per kWh and delivery about 14.1 cents, so delivery was about 53% of the combined cost (Billix calculation from EIA-861 data)^[2]. These households are concentrated in higher-cost states, so this is not a national average, but it shows how delivery can be the larger half.

Why delivery costs have been growing

EIA reported in 2025 that utility spending on electricity distribution had surpassed spending on transmission and on production^[5]. Looking at the largest utilities from 2003 to 2023, after inflation, EIA found that spending on generation fell about 24%, transmission spending nearly tripled, and distribution capital spending reached about $50.9 billion in 2023, up 160% from 2003^[4].

The reasons EIA lists include replacing aging equipment, hardening the grid against storms and wildfires, putting lines underground, connecting new power sources, transformer shortages, and installing smart meters and sensors^[4]. A July 2026 review by Lawrence Berkeley National Laboratory found that investor-owned utilities' distribution spending grew about 5% a year after inflation from 2019 to 2025, with the largest price effects in California, New York and New England^[6].

Retail choice and the "price to compare"

In some states you can buy the supply half from a competitive supplier while your utility keeps delivering the power. As of EIA's last count, published in 2018, 13 states and the District of Columbia had active statewide residential retail choice, and Texas's main grid region requires it^[3]. In most of the country, one utility handles both halves and there is no supplier to switch to.

Where choice exists, regulators publish a price to compare. Pennsylvania's commission defines it as the cost per kWh charged to customers who have not selected a competitive supplier, and notes that generation may account for roughly 50% or more of a total bill^[7]. Labels are not standardized: in Illinois, ComEd's price to compare combines the supply charge and the transmission services charge, so transmission sits in the supply section there^[8]. In many other states, transmission appears under delivery.

Texas shows the delivery half especially clearly. Retail providers pass through the local wires company's charges, which the Public Utility Commission of Texas publishes. As of October 1, 2026, Oncor's delivery charges came to about $64 for 1,000 kWh^[9].

Riders and adjustments can land in either half

Separate cost-recovery lines, often called riders, sit in both sections. A fuel or purchased-power adjustment usually belongs with supply, because it tracks what the utility pays for energy. Storm recovery, wildfire mitigation and grid-modernization charges usually belong with delivery. Lawrence Berkeley National Laboratory's review of utility tariffs found 2025 storm-recovery charges such as 2.5 cents per kWh at Central Maine Power and temporary storm surcharges of 0.9 to 3.2 cents per kWh at four Florida utilities, and estimated that wildfire mitigation costs add more than 4 cents per kWh in California^[6].

Supply prices change too, on their own schedule. In Pennsylvania, default supply prices reset on June 1 and December 1. For June 1, 2026, the commission listed PECO's price to compare rising from 11.024 to an estimated 11.572 cents per kWh and PPL's from 12.953 to 13.147 cents^[7]. In Illinois, ComEd's price to compare for October 2026 through May 2027 is 10.103 cents per kWh: 8.413 cents for supply plus 1.69 cents for transmission^[8]. Because each state packages these lines differently, comparing your own bill year over year is usually more useful than comparing with another state.

Reading the split on your own bill

1. Find the section headers. Look for words like Supply, Generation or Energy Charges, and Delivery, Distribution or Transmission.
2. Add up each section, including its share of riders, but leave out taxes for now.
3. Divide each total by your kWh to get cents per kWh for supply and for delivery. Remember that the fixed customer charge is usually in delivery, which pushes delivery's per-kWh number up in low-use months.
4. If you are in a choice state, compare the supply cents per kWh with your utility's current price to compare. Delivery will be the same whichever supplier you use.

Want to try it with real numbers? Our electricity cost calculator lets you plug in your all-in price per kWh. For the full line-by-line walk-through, see How to read your electric bill.