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Gas vs electric heating: which costs less?

By Last reviewed

Multiply your gas c/MJ by 3.6, then divide by the heater's efficiency. That is the cost of 1 kWh of heat. On the Victorian rates below it is 17.19c for flued gas, 7.77c for reverse-cycle and 27.2c for a plug-in electric heater.

Your room and heater

Sets the heat needed. Every heater gets the same.

Between 1 and 500

Between 0 and 24

Between 1 and 365

Yes only if you would cancel gas without this heater. Adds a full year of it.

Pick yes or no

Your rates

Between 0 and 200

Check your bill. $/MJ × 100 = c/MJ.

Between 0 and 20

Between 0 and 400

Advanced settings
Advanced

Estimate. CHOICE rule of thumb.

Between 20 and 300

Type a heater's kW to use it.

Between 0.1 and 50

Estimate. Same for every heater.

Between 10 and 100

Estimate. See the energy label.

Between 1 and 7

Estimate. Type your own if you know it.

Between 40 and 100

See result ↓

Your result

Per winter

$131

Flued gas heater: 764 kWh of heat at 17.19c each

An hour on full
$0.34
Over the cheapest
$72
Heat output
2kW
Hours a winter
546
Cheapest at this heat
Reverse-cycle air conditioner
$59 a winter
Rates used
27.2c/kWh · 3.82c/MJ gas

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Every heater, same heat
HeaterAn hourA winterExtra
Fan heater$0.54$208$149
Oil column$0.54$208$149
Panel or convection$0.54$208$149
Radiant or infrared$0.54$208$149
Reverse-cycle$0.16$59Cheapest
Flued gas$0.34$131$72

Each row gives 2 kW of heat for 546 hours at 70% thermostat on-time. An hour is on full. Extra is the winter cost above the cheapest heater, marked "Cheapest".

How we calculated this

  • The room size sets the heat needed. Hours, days and thermostat on-time add it up over a winter.
  • Each heater type has its own price for a kWh of heat, from its efficiency and its fuel.
  • The cost is the heat times that price, so every heater is compared on the same heat.

Full method, tables and sources: Heater running cost comparison

  1. Work out the heat the room needs

    2 kW

  2. Add up the heat over a winter

    764 kWh of heat

  3. Price 1 kWh of heat for each heater

    27.2c electric · 7.77c reverse-cycle · 17.19c gas

  4. Multiply out your heater

    764 kWh × 17.19c = $131

Gas is sold by the megajoule and electricity by the kilowatt hour, so the two prices are hard to compare. This version starts with a flued gas heater on Victorian rates, then puts every heater on the same heat.

What we found

Dated third-party source

  • The Victorian default gas price is the Finder market average on the AGN network, last checked September 2026: 3.82c/MJ for the first block and a 90.36c daily supply charge. The Origin Energy standing offer (4.466c/MJ and 104.962c a day, Victoria Government Gazette S280) is the upper end of the market.

Official source

  • Victoria banned the sale of open-flued gas heaters that cannot shut down automatically if they spill carbon monoxide, from 1 August 2022 (Energy Safe Victoria, via Consumer Affairs Victoria).
  • Western Australia banned the sale of open-flued gas heaters without the new safety shutdown features. The prohibition order was issued on 10 October 2022.
  • WA gas bills use units of 3.6 MJ. The regulated maximum of 19.06c per unit is 5.29c/MJ (Energy Policy WA, updated 30 June 2026).

If heating is your last gas use besides the cooktop, see what leaving gas saves →

Gas heater safety

A faulty or badly vented gas heater can fill a room with carbon monoxide, which you cannot see or smell. Fit a carbon monoxide alarm. This calculator only covers flued gas heaters.

  • Victoria: Since 1 August 2022, open-flued gas heaters that cannot shut down automatically if they spill carbon monoxide cannot be sold. Source: Consumer Affairs Victoria.
  • Western Australia: A prohibition order of 10 October 2022 bans the sale of open-flued gas heaters without the new safety shutdown features. Source: WA Government.

Rules differ by state. Check with your state's gas safety regulator, for example:

Why compare at the same heat? Read the full guide on the main heater running cost comparison.

Questions

How many MJ are in a kWh?

Exactly 3.6 MJ. WA bills use "units" of 3.6 MJ, so divide the c/unit price by 3.6 to get c/MJ.

Is gas heating 100% efficient?

No. A flued heater sends some heat up the flue with the exhaust. Set your heater’s efficiency under Advanced settings.

Is it worth switching off gas altogether?

The daily supply charge decides that, because you pay it all year. Set "Count the gas supply charge?" to Yes to add a full year of it to the gas heater.