Gas and electricity tariffs have two parts:

  • the daily supply charge
  • the usage charge.

Daily supply charge

The daily supply charge is also known as the:

  • service charge (or service to property charge)
  • fixed charge.

This is the cost of getting electricity or gas to your home or small business, even if you don’t use any.

You might see it on your bill:

  • in cents per day
  • as the total amount for the billing period.

Usage charge

The usage charge is also known as the:

  • consumption charge
  • variable charge.

This is the cost of the electricity or gas that you use.

You might see it on your bill in:

  • cents per kilowatt hour (c/kWh) for electricity
  • cents per megajoule (c/MJ) for gas.

Some bills might show more than one usage charge.

For example, a time-of-use plan might have different usage charges for different time periods, which are usually called:

  • peak
  • shoulder
  • off-peak.

Your retailer can calculate the usage charges on your bill in different ways, depending on your plan.

How tariff blocks look on a bill

Some energy plans split your energy usage into different tariff blocks. With tariff blocks, you pay:

  • one rate or cost for the first part of your usage, then
  • a different rate or cost for the next part (or parts) of your usage.

Blocks can apply to:

  • daily
  • monthly
  • quarterly usage.

For time-of-use electricity plans, blocks can also apply to the different rates that make up a tariff.

For example, you get charged one rate for the first part of your peak usage, then a different rate for the next part.

Have a look at our sample electricity and gas bills to see examples of how tariff blocks might look on your bill.