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FrugalWatt / Electric bill explainer

Your bills. A clearer answer.

Why did my electric bill go up?

More electricity? A longer billing period? A higher effective price? Compare two bills and see how the numbers fit together.

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Grab your two electric bills

Use current-period electric charges, including supply, delivery, fixed charges and taxes. Exclude previous balances, payments, late fees and other services such as gas. Do not use “total amount due” if it includes those items.

Compare the same account and currency (USD). Budget-plan payments, net export/zero-kWh bills and negative credits need a line-by-line review instead.

01 Earlier bill
Charges for this billing period only.
Use the billed kWh, not the meter reading.
Use the number of service days on the bill.
02 Later bill
Charges for this billing period only.
Use the billed kWh, not the meter reading.
Use the number of service days on the bill.

What this comparison can—and cannot—tell you

This is an exact accounting breakdown, not a diagnosis. Weather, occupancy and appliances may affect usage, but two bill totals cannot identify the cause.

Effective price = current-period charges ÷ kWh. It blends energy rates, fixed fees, taxes, credits and usage mix. A change does not prove your utility raised its tariff. Fixed charges alone can make effective price rise when usage falls.

We first change billing days at the earlier daily usage and effective price; then change daily usage at the earlier effective price; then change effective price at the later kWh. These three amounts add to the total change before rounding. Changing the order would allocate the interaction differently. This is not a forecast of marginal savings.

With earlier values C₀, K₀, D₀ and later values C₁, K₁, D₁: billing days = (D₁ − D₀) × (K₀ / D₀) × (C₀ / K₀); daily usage = (K₁ / D₁ − K₀ / D₀) × D₁ × (C₀ / K₀); effective price = K₁ × (C₁ / K₁ − C₀ / K₀).

Keep going: explore home energy savings or see state electricity price trends. State averages are context, not a comparison with similar homes.