Start with the biggest lever: your plan
Most households never switch gas plans, yet the gap between a stale offer and a sharp one can be worth hundreds of dollars a year. Retailers rely on inertia — they quietly move you off an introductory discount and onto standing rates once your benefit period ends, and the increase rarely arrives with a warning that feels like one.
The single most effective thing you can do is compare your current plan against what is available today. Gas is billed differently from electricity, so a good comparison has to account for stepped (block) rates and supply charges, not just a single headline number. EnergySorted costs each plan against your real usage, including the way stepped rates change the price of each megajoule as you use more, so the ranking reflects what you would actually pay rather than a marketing figure.
Before you compare, grab a recent bill. You want your annual or quarterly usage in megajoules (MJ), your supply (daily) charge, and your usage rates. With those three things, a comparison tells you the truth in a couple of minutes.
Understand how gas is priced
Gas usage is measured in megajoules, and most plans use stepped rates. That means the first block of gas each billing period is charged at one rate, the next block at a lower rate, and so on. Heavy winter usage can push you into cheaper steps, which is why comparing plans on a flat average can be misleading.
On top of usage you pay a daily supply charge that applies whether you burn any gas or not. For low-usage households — a couple who cook with gas but heat with a reverse-cycle split system, say — the supply charge can be the majority of the bill, so a plan with a low daily charge matters more than a sharp usage rate.
- Megajoule (MJ)
- The unit gas is billed in. A typical home uses somewhere between 10,000 and 30,000 MJ a year depending on climate and how much gas heating it runs.
- Stepped (block) rate
- A pricing structure where the per-MJ price changes after you pass a usage threshold within a billing period. Later blocks are usually cheaper.
- Supply charge
- A fixed daily fee for being connected to the gas network, charged regardless of how much gas you use.
Trim the usage that actually costs you
- Tackle hot water first — it is the largest gas load in most homes. Shorter showers, a water-efficient showerhead and washing clothes in cold water all chip away at it.
- Set your gas heating deliberately. Every degree above about 20°C on a ducted or space heater adds noticeably to winter usage; heating only the rooms you use beats warming the whole house.
- Seal draughts around doors, windows and unused vents so your heater is not fighting cold air leaks. This is cheap and pays back quickly.
- Check your hot water system temperature. Storage systems set far hotter than needed waste gas keeping water hot around the clock.
- For cooking, a lid on the pot and right-sized burner make a small but real difference over a year.
Review the extras and the fine print
Pay-on-time discounts, direct debit conditions and the length of a discount period all change the real cost of a plan. A plan advertising a big percentage off can end up dearer than a plan with a modest discount but lower base rates — the discount is applied to rates that were higher to begin with.
Concessions matter too. Every mainland state and the ACT offers energy concessions for eligible pensioners and concession-card holders; these are applied by your retailer once you register, so make sure yours is recorded. If you have both gas and electricity, ask whether a dual-fuel offer beats keeping them separate — sometimes it does, often it does not, and only costing it on your usage settles the question.