Gas bill calculator
Estimate your annual gas bill based on your postcode, household size, and gas appliances — and see how much you could save by switching providers.
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Estimates are indicative only and based on average published rates. Actual bills vary by usage, plan terms, and distributor. EnergyPlans.com.au is an independent platform.
Example gas bill calculation
To illustrate how a gas bill is calculated, here is a worked example for a typical 3-bedroom NSW household with gas hot water and a gas cooktop:
3-bedroom NSW household — gas hot water & cooking
- Daily appliance usage: hot water (14 MJ) + cooking (4 MJ) = 18 MJ/day
- Annual usage: 18 × 365 = 6,570 MJ
- Usage cost (at 2.72c/MJ): 6,570 × $0.0272 = $178.70
- Annual supply charge (at $0.88/day): $0.88 × 365 = $321.20
- Estimated annual gas bill: ~$500
Note: SA households with gas central heating typically pay $800–$1,100/year due to higher usage (22 MJ/day) and SA's higher average rate of 3.05c/MJ. Victorian households with ducted heating often pay more in winter due to usage spikes above 26 MJ/day.
Actual costs vary by state, plan, distributor, and household. Always compare plans to find the cheapest available rate.
How gas bills are calculated in Australia
Australian gas bills are made up of two components charged by your retailer:
- Usage rate (c/MJ): A charge for every megajoule (MJ) of gas you consume. This is the main variable cost. Usage rates in Australia typically range from 2.45c/MJ (QLD) to 3.05c/MJ (SA).
- Daily supply charge ($/day): A fixed daily fee for being connected to the gas network, regardless of usage. This covers distribution infrastructure costs.
Average gas usage by state
Typical household gas usage varies significantly by state, largely due to climate and reliance on gas for heating.
| State | Avg. rate (c/MJ) | Avg. daily usage (MJ) | Est. annual bill |
|---|---|---|---|
| NSW | 2.72c | 22 MJ | ~$540 |
| VIC | 2.58c | 26 MJ | ~$551 |
| QLD | 2.45c | 14 MJ | ~$417 |
| SA | 3.05c | 22 MJ | ~$595 |
Estimates based on typical 3-bedroom household with gas hot water and heating. Actual bills vary by usage pattern and specific plan.
Understanding gas pricing — c/MJ explained
In Australia, gas is priced in cents per megajoule (c/MJ). This differs from electricity, which is priced in cents per kilowatt-hour (c/kWh). If you see a gas rate quoted in kWh, you can convert it using:
For example, a rate of 2.72c/MJ is approximately 9.8c/kWh. When comparing gas plans, always compare using the same unit (c/MJ) and ensure you account for the daily supply charge, which is a significant part of the total cost.
This analysis is based on EnergyPlans Australia's 2026 energy pricing data across multiple providers and states.
Last updated: 1 April 2026.
Frequently asked questions
How is my gas bill calculated in Australia?
Your gas bill has two main components: a usage charge (c/MJ × your consumption in megajoules) and a daily supply charge (a fixed fee per day for network access). Annual bill = (usage rate × annual MJ used) + (daily supply charge × 365).
What is the average gas bill in Australia?
Average annual gas bills range from approximately $500 in QLD (lower heating usage) to over $1,000 in VIC and SA (high heating demand). NSW households typically pay $600–$900/year depending on appliances.
What does c/MJ mean on a gas bill?
c/MJ means cents per megajoule — the unit used to measure gas consumption in Australia. One kilowatt-hour (kWh) is approximately 3.6 MJ, so a rate of 2.72c/MJ is equivalent to about 9.8c/kWh.
How can I lower my gas bill?
The most effective way to lower your gas bill is to compare plans and switch to a cheaper retailer. You can also reduce usage by improving insulation, using a programmable thermostat, and servicing gas appliances regularly.
Can I switch gas providers to save money?
Yes. In NSW, VIC, QLD, and SA, you can freely compare and switch gas retailers. Switching to a cheaper market offer can save $100–$300/year. Use our comparison tool to see available plans in your area.