Electricity Bill Calculator
Work out your monthly electricity bill and see what actually drives it. Enter your usage and rates from any country, including tiered and time-of-use plans. You also see what one more unit costs, which is the number that matters when you compare solar or a new appliance.
Your monthly bill
Using 600 kWh a month would cost about $108, or $1,296 a year.
- Energy$108 (100%)
| Point | Monthly bill |
|---|---|
| 0 kWh | $0.00 |
| 60 kWh | $11 |
| 120 kWh | $22 |
| 180 kWh | $32 |
| 240 kWh | $43 |
| 300 kWh | $54 |
| 360 kWh | $65 |
| 420 kWh | $76 |
| 480 kWh | $86 |
| 540 kWh | $97 |
| 600 kWh | $108 |
| 660 kWh | $119 |
| 720 kWh | $130 |
| 780 kWh | $140 |
| 840 kWh | $151 |
| 900 kWh | $162 |
| 960 kWh | $173 |
| 1,020 kWh | $184 |
| 1,080 kWh | $194 |
| 1,140 kWh | $205 |
| 1,200 kWh | $216 |
Assumptions used
- Starting rate
- National residential average forecast for 2026. States differ widely
- Tariff
- Flat
- Charges not included
- Demand charges, fuel adjustments, and levies
What if?
Save this result, change any setting, and compare.
How this is calculated
Energy charge
A flat tariff multiplies your units by one rate. A tiered tariff charges each band of units at that band's rate. A time-of-use tariff splits your units between peak and off-peak prices.
Fixed charges and tax
Fixed charges apply whatever you use. Tax is then added on top of the energy and fixed charges.
Bill = (energy charge + fixed charge) × (1 + tax rate)
Average rate and next unit
Your average rate is the whole bill divided by your units. The next-unit cost is what your bill would rise by if you used one more unit. On a tiered plan the two can be very different, and solar saves you the next-unit rate first.
Worked example: a 600 kWh tiered bill
With 200 units at $0.144, the next 300 at $0.18, and the rest at $0.234, a 600 kWh month costs $106.20.
That is an average of $0.177 a unit, but the next unit costs $0.234, because you are already in the top band.
How accurate is this?
The sums are exact for the rates you enter. Real bills can add charges we do not model, such as fuel adjustments, demand charges, and regional levies, so check the result against one real bill.
Common mistakes
- Dividing your bill by your units and treating that as your saving per unit
- Forgetting that fixed charges stay when you use less
- Using one month's bill when winter and summer use differ a lot
- Assuming all tiers apply to all units. Most tiers charge each band separately
Limits of this tool
- Demand charges and seasonal rates need your supplier's exact tariff
- Tax is applied to the whole bill, which is not true in every region
- Time-of-use results depend on your estimate of peak use
What to do next
- Take your next-unit rate into the solar savings calculator
- Check which appliances use the most with the AC energy calculator
Frequently asked questions
How do I calculate my electricity bill?
Multiply your units by your rate, add any fixed charge, then add tax. For tiered tariffs, charge each band of units at its own rate before adding the rest.
What is a unit of electricity?
One unit is one kilowatt-hour, or kWh. A 1,000 watt appliance running for one hour uses one unit.
Why is my average rate different from my tariff rate?
The average includes fixed charges, taxes, and every tier, so it rarely matches any single rate on your tariff.
What is time-of-use pricing?
Your supplier charges more during busy hours and less at quiet times, so moving use to cheaper hours lowers your bill.