Your electric bill has two main parts: a flat monthly fee for being connected, and a charge for how much electricity you actually used. Use is counted in kilowatt-hours. The rest is delivery charges and taxes stacked on top.
Electric bills look like they were designed to confuse you. They were not — but nobody translated them, either. Here is the translation.
The kilowatt-hour, without the headache
Electricity is sold by the kilowatt-hour, written kWh. One kWh is 1,000 watts running for one hour. Picture a bright old-school bulb using 100 watts: leave it on for 10 hours and you used exactly 1 kWh. A big appliance like a dryer might use 3 kWh in one load. Your bill takes everything your home ran all month and adds it up in kWh.
The lines on the bill
Customer charge: a flat fee, often $8 to $15, that you pay just for having service. You owe it even if you use almost nothing. Supply or energy charge: the cost of the electricity itself — your kWh times the price per kWh. Delivery charge: what the utility charges to bring power to your home over its wires. Some bills split these apart; some roll them into one rate. Either way, you are paying for the power and the trip it took to reach you.
Say your home used 900 kWh last month and your all-in price works out to about 15 cents per kWh. That is $135 for electricity. Add a $12 customer charge and a few dollars of taxes and fees, and you land near $155 — before any late fees or add-on programs.
Why the bill jumps
Heating and cooling are the big swing. A hot month means the air conditioner runs for hours, and hours are what you pay for. The bill also shows two dates — when the meter was read last month and this month — so a “month” with 35 days between readings costs more than one with 28. If a bill says estimated, the company guessed your use and will correct it on a later bill.