Check a rate change with stable consumption

A townhouse uses exactly 300 kWh in two consecutive periods. A tariff notice took effect between them and the bill rose despite unchanged usage.

Inputs and calculation

Usage: (300 − 300) × 0.18 = 0. Rate: 300 × (0.23 − 0.18) = 15. Actual bill difference: 79 − 64 = 15. Residual: 15 − (0 + 15) = 0. All effects are in USD.

Tool result · USD 15.00

Usage: (300 − 300) × 0.18 = 0. Rate: 300 × (0.18 − 0.18) = 0. Actual bill difference: 64 − 64 = 0. Residual: 0 − (0 + 0) = 0. All effects are in USD.

Tool result · USD 0.00

What the comparison shows

The five-cent price rise explains the full 15.00. Reducing usage could offset some of it, but the increase itself comes from the unit price.

Assumptions and limits

Enter the flat supply rate printed on each bill. A period split across tariff dates may need a separate weighted calculation.

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