Electricity bills look complicated, but almost everything on them comes down to two charges and a handful of numbers. Once you know where to look, you can pull everything you need to compare your plan against every other retailer in your State in a few minutes.
The two charges behind every bill
Nearly every Australian electricity bill is built from the same two ingredients.
The daily supply charge is a fixed amount, usually shown in cents per day, that you pay just to be connected to the network. It does not change with how much power you use. Over a year, a supply charge of 120 cents a day is about $438 before you switch on a single light.
The usage charge is a rate per kilowatt-hour (kWh) for the electricity you actually use. On a single-rate (flat) tariff there is one anytime rate. On a time-of-use tariff, the rate changes by time of day, with peak, off-peak and sometimes shoulder periods.
Everything else on the bill, from discounts to concessions to solar credits, is an adjustment layered over those two charges.
Where to find each number
Bills differ between retailers, but these items appear on almost all of them.
- Billing period and days. Usually near the top: the start date, end date and the number of days covered. You need the day count to turn totals into daily figures.
- Your NMI. The National Metering Identifier is the unique number for your property's connection. You will be asked for it (or your address) when you switch.
- Supply charge. Listed in the charges breakdown as cents per day, multiplied by the number of days in the period.
- Usage. Shown in kWh, either as a single line (flat rate) or split into peak, shoulder and off-peak lines (time of use).
- Controlled load. If you have electric hot water or another appliance on a separately metered circuit, it appears as its own usage line at its own, usually cheaper, rate. Naming varies by State: it may say controlled load, dedicated circuit, or a tariff number. Our controlled load guide covers the differences.
- Average daily usage. Many bills show this directly, sometimes with a comparison to similar households. If yours does not, divide the period's total kWh by the number of days.
- Read type. Bills note whether the meter reading was actual or estimated. An estimated read means the retailer guessed your usage, and the next actual read will square things up. A surprisingly high bill is sometimes just an estimate.
The better offer box
Look for a box on the bill, usually on the first page, with a heading like "Could you save money on another plan?"
In Queensland, New South Wales, South Australia, Tasmania and the ACT, the Australian Energy Regulator requires retailers to check whether they have a cheaper plan for you, based on your actual usage, and print the answer at least every 100 days. In Victoria, the Essential Services Commission requires a best offer message on the front of electricity bills at least every 3 months.
It is one of the most useful things on the bill, and it is easy to skim past. If it says you could save by switching plans with your current retailer, that saving usually takes one phone call or a few clicks.
The four numbers you need to compare plans
To compare your current plan against the rest of the market like-for-like, pull these from your bill:
- Your average daily usage in kWh (total kWh divided by billing days).
- Your controlled load daily usage in kWh, if you have one (otherwise zero).
- Your current supply charge in cents or dollars per day.
- Your current usage rate(s) in cents or dollars per kWh.
That is exactly what our free calculator asks for. Enter your usage once, and it works out the daily, monthly and yearly cost of your current plan next to every other retailer you add. In Queensland, New South Wales, Victoria, South Australia, Tasmania and the ACT you can also import real plans for your postcode from government data instead of typing them in.
Pick your State and see where your current plan really sits.
A note on GST and discounts
Advertised electricity rates in Australia are generally quoted inclusive of GST on comparison sites and government data, but some bills itemise GST separately, so check whether the rates on your bill are GST-inclusive before comparing them with advertised rates. Conditional discounts (like pay-on-time discounts) only help if you reliably meet the condition, so when in doubt, compare base rates.