The first check: usage or price?
Divide the kWh on your bill by the number of days in the billing period. That gives your kWh a day. Do the same for last year's bill for the same season. If kWh a day went up, you used more. If it stayed about the same but the bill rose, the price changed or the billing period was longer.
For context, the AER's consumption benchmarks put a two-person Sydney home at about 14 kWh a day across the year, more in winter and less in spring. Our two-person bill guide and the other household size guides show the figures for each capital.
Common reasons for a high bill
| Cause | How to spot it |
|---|---|
| Seasonal heating or cooling | kWh a day is up in winter or summer, similar to last year's same season. |
| Catch-up after estimated reads | The previous bill was marked E or estimated, and this one has an actual read. See estimated reads. |
| A price change | The rate per kWh or the daily supply charge is higher than last bill. Most prices change on 1 July. |
| A discount or benefit ended | A line for a discount is missing, or the plan name changed. |
| A longer billing period | More days than usual means more supply charges and more usage. |
| A missing concession or solar credit | A line that was on earlier bills is gone. |
| Someone new at home | Working from home, a new baby, visitors or a new pet that needs heating. |
Appliances that push bills up
If your usage really did rise, these are the usual suspects. Each link opens a calculator for that appliance.
| Appliance | Why it adds up | A year |
|---|---|---|
| Pool pump | Runs for hours every day | $798 |
| Hot water system | Heats water every day of the year | $949 |
| Air conditioner | Heating and cooling in extreme weather | $907 |
| Electric heater | Plug-in heaters on cold nights | $1,161 |
| Clothes dryer | Vented dryers in winter | $171 |
| Refrigerator | Especially a second fridge in the garage | $164 |
Faults that quietly add hundreds
A hot water system with a failing thermostat or a leaking hot tap, a pool pump timer that is stuck on, or a heated towel rail nobody knew was running can add hundreds of dollars a year. Check your switchboard and your smart meter data overnight, when usage should be low.
What to do next
Check the read type and dates
Make sure the bill uses an actual read and the period follows on from the last bill.
Check your rates
Compare your usage and supply rates with the regulated price for your network on our rates by state page.
Look at your half-hourly data
Most retailers show smart meter data online. A high overnight base load points to something always on. See reading smart meter data.
Find the big user
Switch suspect appliances off one at a time and watch the meter, or use a plug-in power meter. See measuring energy use.
Query the bill
If the bill looks wrong, call your retailer and ask them to check it. If that does not resolve it, contact your energy ombudsman.
Questions about high electricity bills
The usual reasons are colder or hotter weather, an estimated read being corrected, a price change on 1 July, a discount or benefit period ending, or a longer billing period. Compare kWh per day with the same bill last year to tell usage from price.
Divide the kWh on your bill by the days in the period and compare it with the AER benchmark for your household size and city. A two-person Sydney home averages about 14 kWh a day across the year in the AER's figures.
Heating and cooling, hot water and pool equipment in most homes. energy.gov.au puts heating and cooling at 20% to 50% of household energy use and water heating at 15% to 30%.
It is rare, but possible. Rule out estimated reads, price changes and appliance faults first. If you still think the meter is wrong, ask your retailer for a meter test, which may carry a fee if the meter is accurate.
Your retailer first. If it is not resolved, the free energy ombudsman in your state. You generally only need to pay the part of a bill that is not in dispute while a complaint is open.
Sources
Every rate on this page comes from the regulator or the regulated retailer. Last checked October 2026. Prices include GST unless we say otherwise.