Electricity Bill Check Calculator
Check whether your electricity bill adds up correctly by re-calculating it from your usage, tariff and supply charge.
Your results
Calculation breakdown
- Expected bill
- Expected = (usage × usage rate) + (daily supply charge × days)
Worked example
900 kWh at 30c/kWh plus a $1.10 daily charge over 90 days gives an expected bill of $369, so a $380 charge is $11 higher than expected, worth checking with your retailer.
Assumptions
- Small differences can be explained by GST or rounding; only large gaps suggest a billing issue.
- Excludes controlled load, feed-in credits or one-off fees unless added manually.
- Compare using GST-inclusive figures throughout for accuracy.
How this calculator works
Enter the usage in kWh and days on your bill along with your usage rate and daily supply charge to recalculate the expected total, then compare it to the amount your retailer actually charged. This can help spot billing errors or a rate change you were not aware of.
Check the main parts of an electricity bill
For a flat-rate plan, multiply electricity use in kilowatt-hours by the usage rate, then add the daily supply charge for every day in the billing period. Add any other applicable fees and subtract credits, rebates or feed-in tariff amounts shown on the bill.
Time-of-use, controlled-load and demand plans need each charge calculated separately. Copy the units and rates from the same bill because prices can change between plans and billing periods.
- Usage charge = kWh × cents per kWh
- Supply charge = billing days × daily charge
- Check whether rates and totals include GST
Actual versus estimated meter readings
Check whether the retailer marked the reading as actual or estimated. An estimated reading can later be adjusted when an actual reading becomes available, so it may not match your meter or smart-meter data for that period.
This calculator checks the arithmetic from the figures entered. Contact the retailer if the tariff, meter reading, billing dates or account adjustments appear wrong.
Official sources and assumptions
Check the underlying Australian Government guidance used to review this calculator's rates and assumptions.
Frequently asked questions
What if my recalculated total doesn't match my bill?
Small differences can arise from GST rounding or discounts; a large gap is worth raising with your retailer or checking for a rate change.
Where do I find my usage rate and supply charge?
Both are listed on your bill, usually in a section titled 'your electricity charges' or similar, in cents per kWh and cents per day.
Does this include GST?
Toggle the GST setting depending on whether your entered rates are GST-inclusive or exclusive to match your bill exactly.
Editorial review and responsibility
Reviewed by the CalcAussie editorial team on 21 September 2026. Review scope: Method, Australian terminology, material assumptions, source links and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.
Actual prices, usage, efficiency and savings vary by provider, equipment, location and behaviour.