Check whether daily electricity use really rose

After a meter-reading date changes, two bills cover 28 and 35 days. Both periods average 8 kWh per day.

Inputs and calculation

Usage: (280 − 224) × 0.25 = 14. Rate: 280 × (0.25 − 0.25) = 0. Actual bill difference: 80 − 66 = 14. Residual: 14 − (14 + 0) = 0. All effects are in USD.

Tool result · USD 14.00

Usage: (224 − 224) × 0.25 = 0. Rate: 224 × (0.25 − 0.25) = 0. Actual bill difference: 66 − 66 = 0. Residual: 0 − (0 + 0) = 0. All effects are in USD.

Tool result · USD 0.00

What the comparison shows

A 25% larger usage total reflects 25% more billed days. Neither daily rate of use nor the unit price changed in the sample.

Assumptions and limits

The Detective uses period totals. Divide by days separately, and compare like-for-like weather and occupancy where relevant.

Related guides and examples

• Why your utility bill changed
• Estimated meter readings and catch-up bills
• A practical investigation of an unexpectedly high water bill
• Compare bills with different billing days
• Compare an estimated statement with a catch-up read
• Read a trend when a bill is missing