For an appliance electricity-cost estimate, start with the charges that change when you use another kilowatt-hour. That can include both supply and usage-based delivery charges, not just the largest rate printed on the front of the bill. A fixed monthly customer charge usually does not increase because you run a dryer one more time.
This guide shows how to read an electric bill, distinguish a household’s average billed cost from an incremental appliance estimate, and enter the appropriate rate in a calculator. Examples are fictional and do not represent a current offer from any utility.
1. Find the billing period and electricity usage
Locate electricity consumption in kWh and the dates it covers. A bill may cover more or fewer than 30 days. Check whether electricity is combined with gas, whether there is a separate supplier statement, and whether an amount is a past balance rather than a current charge.
Do not divide a combined gas-and-electric payment or an amount including arrears by electric kWh. That ratio would not describe this period’s electricity cost.
2. Separate supply, delivery and fixed charges
Con Edison’s bill-reading guide distinguishes supply, delivery and taxes. Your utility may use different labels, and a delivery section can contain both fixed and usage-based components.
| Bill item | How it may be charged | How to treat it |
|---|---|---|
| Electricity supply | Dollars or cents per kWh | Include the applicable variable rate |
| Delivery | Per kWh and/or a fixed amount | Separate the variable component |
| Customer/service charge | Fixed amount per billing period | Keep separate from an extra-use estimate |
| Fuel or other adjustments | May vary with usage | Check the unit and whether already included |
| Taxes, credits and demand charges | Tariff-specific | Need separate treatment; not covered by the mini calculator |
The word “delivery” does not mean the entire delivery total should be excluded. Equally, it does not mean every delivery dollar is a per-kWh charge. Read the line items and current tariff, or ask your utility to identify charges that change with usage.
3. Two valid rates answer different questions
Average billed cost per kWh = current-period electricity charges ÷ current-period electric kWh. This can help describe what your household paid overall, including the fixed costs included in your chosen numerator.
Incremental variable rate = applicable supply + variable delivery + other applicable per-kWh adjustments. This is usually the more useful starting point for estimating an additional appliance’s energy charge under a simple flat-rate plan. It is not a universal formula for every tariff.
The EIA explains its average retail price statistics as revenue per kWh. Those statistics provide context; they are not a lookup for your individual contract or the next kWh you consume.
4. A fictional bill, worked through
Suppose a household uses 600 kWh and has these current-period electric charges, with no taxes, credits or other fees in this simplified example:
- Supply: 12¢/kWh = $72.
- Variable delivery: 7¢/kWh = $42.
- Other variable adjustment: 1¢/kWh = $6.
- Fixed customer charge: $15.
Total: $135. Average billed cost: $135 ÷ 600 = $0.225, or 22.5¢/kWh. The combined variable rate is 12 + 7 + 1 = 20¢/kWh.
A 1,500W appliance running for one hour uses 1.5 kWh. At that variable rate, its energy charge is 1.5 × $0.20 = $0.30. Multiplying by the average billed rate gives $0.3375 instead, allocating some fixed cost to the appliance. Both calculations have a meaning, but they answer different questions.
5. Convert dollars and cents correctly
If your tariff shows $0.12/kWh, enter 12 in a calculator labeled cents/kWh. Entering 0.12 would make the result 100 times too small. For a rate shown as 20¢/kWh, enter 20, not 0.20.
Make sure an adjustment is not already included in the quoted combined rate. Do not add the same supply or delivery amount twice. The widget below accepts non-negative per-kWh components only; credits or more complicated adjustments require a separate calculation.
6. When one rate is not enough
- Time-of-use: multiply each period’s appliance kWh by that period’s applicable rate, then add the costs.
- Tiered pricing: an extra appliance may cross a threshold, so the household average may not describe its incremental cost.
- Demand charges: maximum kW can matter in addition to total kWh.
- Solar, credits or minimum bills: import/export rules and minimum charges may change the bill effect.
As a fictional TOU example, 2 kWh at $0.15 plus 1 kWh at $0.35 costs $0.65. Applying either price to all 3 kWh would give a different result. Actual peak periods and eligibility must be checked for your utility and plan.
7. Keep a small calculation record
Write down the utility, rate-plan name, tariff effective date, usage period and the line items you included. You do not need to enter your name, account number, address or upload a bill to use our calculator. Recheck the rate when the tariff changes.
Once you have a suitable rate, explore our dryer cost per load or refrigerator annual kWh examples. Their energy-use assumptions differ, but both depend on choosing a rate that matches the question.
Published October 20, 2026. This is an educational estimation guide, not a utility quote or a full bill audit.
What would this cost in your home?
Use your own electricity rate and usage below. These starting values are examples, not current utility quotes.