How to Reduce Your Gas Bill: Practical UK Tips

For most households running a gas combi, system or heat-only boiler, the central heating and hot water account for the lion's share of energy use. The good news is that several of the changes that make the biggest difference are free or low-cost, and you can do them yourself today.

Below we've grouped the most effective tips, from a quick tweak on your boiler to longer-term insulation work.

1. Lower your boiler's flow temperature

This is the single most overlooked saving. Many condensing combi boilers leave the factory with the central-heating flow temperature set far higher than it needs to be — often around 75–80°C. At that temperature the boiler rarely enters condensing mode, where it recovers extra heat from the flue gases and runs most efficiently.

Turning the heating flow temperature down to roughly 50–60°C lets a condensing boiler condense properly, which can noticeably improve efficiency.

Nesta's Money Saving Boiler Challenge estimates that dropping a combi from a typical 75–80°C down to 60°C can cut gas use by around 6–9% — very roughly in the region of £100 a year for an average household (indicative, last checked June 2026; your figure depends on the cap and your usage).

Your home takes a little longer to warm up, so it suits people who heat over longer periods rather than short bursts. This is a homeowner-safe adjustment made on the boiler's controls — it is not gas work. For a full walkthrough, see our guide to boiler flow temperature.

Important: lower the heating flow temperature only. Leave the hot water temperature high enough to stay safe against bacteria — never drop it to lukewarm.

2. Set the thermostat sensibly and use TRVs

Every degree on the room thermostat adds up over a heating season.

Turning the thermostat down by just 1°C is one of the best-known wins: the Energy Saving Trust's long-standing rule of thumb is that it can trim roughly 10% off your heating — often quoted as somewhere in the region of £80–£100 a year for a typical household, though the Trust's own figure varies with the home and the year (indicative, last checked June 2026; varies with the cap).

Set it to a comfortable but not excessive temperature — many people are comfortable around 18–21°C — and resist the urge to crank it higher to "warm up faster". A thermostat is a target, not an accelerator; turning it to 28°C doesn't heat the room any quicker, it just runs the boiler for longer.

• Use TRVs (thermostatic radiator valves) to turn radiators down in rooms you use less, like spare bedrooms.
• Zone your home if you can, so you're not heating the whole house to the same level all day.
• Only heat rooms you actually use — closing internal doors helps keep heat where you want it.

Heating-related quick wins

A few cheap radiator tweaks help the heat you've paid for reach the room instead of being wasted:

• Radiator reflector panels fitted behind radiators on uninsulated external walls bounce heat back into the room rather than letting it escape through the wall. The Energy Saving Trust puts the saving at around £25 a year in Great Britain, for a roll costing roughly £13 (indicative, last checked June 2026). Use purpose-made panels — ordinary kitchen foil won't stay put or work as well.
• Keep radiators clear of sofas, beds and long curtains. Furniture pushed against a radiator soaks up heat instead of letting it circulate, and curtains draped over one funnel warm air straight out of the window. Tuck curtains behind the radiator or onto the sill.
• Bleed radiators if the tops are cold while the bottoms are warm — trapped air stops them heating fully. This is a safe DIY job; see our guide to bleeding a radiator.

3. Use smart controls and a timer

A programmer or smart thermostat lets you heat the home around your routine instead of leaving the heating on constantly. Schedule it to come on shortly before you wake and before you get home, and to wind down before bed.

Smart thermostats add features like learning schedules, geolocation (turning heating off when the house is empty) and app control, which make it easier to avoid heating an empty home.

The Energy Saving Trust estimates that installing a full set of heating controls — a programmer, room thermostat and TRVs — saves a typical Great Britain household around £110 a year; a well-used smart thermostat is broadly in the same ballpark, often quoted at around 5% of heating costs (indicative, last checked June 2026; depends on your current controls and how you use them).

If you're choosing between systems, see our Nest vs Hive comparison.

4. Service your boiler

An annual service by a Gas Safe registered engineer keeps the boiler running efficiently and safely, and catches small faults before they become expensive breakdowns. A poorly maintained boiler can burn more gas to deliver the same heat. To understand what's involved and what it typically costs, read our guide to boiler service cost.

5. Draught-proof and insulate

You can lower the flow temperature and tune the thermostat all you like, but if the heat leaks straight out, you're paying to warm the street. Draught-proofing and insulation reduce how much heat you need to produce in the first place.

• Draught-proof doors, windows, letterboxes and unused chimneys with cheap strips and brushes.
• Loft insulation to the recommended depth is one of the most cost-effective upgrades for many homes.

6. Cut your hot-water costs

Hot water is the second-biggest use of gas in most homes after heating, so a few low-cost changes here add up — particularly if you have a stored hot-water cylinder rather than a combi.

• Efficient or aerated shower heads mix air into the flow, so showers feel just as strong while drawing less hot water. Pair this with shorter showers — cutting a few minutes off each one reduces the gas your boiler burns to reheat the water. (Don't fit a flow restrictor to an electric shower or some combis without checking compatibility.)
• Insulate the hot-water cylinder. Fitting an 80mm British Standard jacket over a cylinder with only thin factory foam can save around £40 a year in Great Britain, for a jacket costing roughly £18 — one of the fastest paybacks of any measure (Energy Saving Trust figures, indicative, last checked June 2026).
• Lag the exposed hot-water pipes with cheap foam tubing where they run through cupboards, lofts or under floors. The saving is small — around £6 a year in GB — but the materials cost very little and it keeps water hotter between the cylinder and the tap (Energy Saving Trust, indicative, last checked June 2026).
• Set an immersion timer if you have an electric immersion heater as backup, so it only heats water around the times you need it rather than around the clock.

7. Keep the system healthy

A few simple, homeowner-safe checks keep your system running as it should:

• Check the pressure on the gauge — typically around 1–1.5 bar when cold, rising toward 2 bar when hot. If it's low, you can usually top it up via the filling loop (check your manual first).
• In winter, a frozen external condensate pipe is a common cause of a boiler cutting out; thawing it gently with warm (not boiling) water often gets things going again.

If you see error codes, leaks, or smell gas, stop and call a professional — never attempt DIY on the gas valve, pipework, flue, sealed circuit, pressure relief valve or boiler casing. For any gas emergency or if you suspect a leak, call the National Gas Emergency line on 0800 111 999 and book a Gas Safe registered engineer.

8. In the kitchen and laundry

If you cook on gas, a few habits trim your gas use directly: use a lid on pans so water boils faster on a lower flame, match the flame to the pan size, and batch-cook to make the most of the heat. Be realistic, though — for most homes the bigger kitchen and laundry savings are on the electricity bill, not gas:

• Wash at 30°C and run full loads — modern detergents work fine cool, and most of a washing machine's energy goes on heating the water.
• Switch off standby on appliances and chargers left idle.
• Only boil the water you need in the kettle.

We've flagged these as mostly electricity savings so you know what to expect — they won't move your gas bill much unless you cook on gas, but they cut your overall energy spend.

9. UK help to save: smart meters, tariffs and grants

Beyond your own habits, there are UK-wide routes that help you monitor and reduce what you pay. This is general information, not financial advice — always check the official sources for the current rules and your own eligibility.

• Get a smart meter so you can see your gas use in near real time on the in-home display. Spotting when usage spikes makes it far easier to act on the tips above. Smart meters are offered by your supplier, usually at no extra upfront cost.
• Check you're on the best tariff. Compare your current deal against the latest Ofgem price cap and any fixed deals available to you — the cap is a backstop, not always the cheapest option. Ofgem's price-cap pages explain how it works.
• Government energy schemes. Depending on your home and circumstances you may qualify for help with insulation or low-carbon heating:
  • ECO4 — support for insulation and heating upgrades for households on certain means-tested benefits in lower-rated (EPC D–G) homes; the current phase runs to 31 December 2026.
  • Boiler Upgrade Scheme (England & Wales) — a grant of up to £7,500 towards an air-source or ground-source heat pump, or £5,000 towards a biomass boiler, applied as a discount on your installation. See our explainer on the Boiler Upgrade Scheme.
  • Great British Insulation Scheme — note this scheme closed to new applications on 31 January 2026, so check GOV.UK for the latest replacement support before relying on it.
• Independent advice is available free from the Energy Saving Trust and via GOV.UK's energy-efficiency support pages.

Scheme names, grant amounts and deadlines change — these are indicative and last checked June 2026. Always confirm the current details and eligibility on GOV.UK before applying.

Quick comparison: effort vs payback

Change	Cost	DIY-safe?
Lower heating flow temperature	Free	Yes
Set thermostat & TRVs sensibly	Free	Yes
Bleed radiators	Free	Yes
Keep radiators clear of furniture/curtains	Free	Yes
Shorter showers & aerated shower head	Low	Yes
Hot-water cylinder jacket & pipe lagging	Low	Yes
Radiator reflector panels (external walls)	Low	Yes
Draught-proofing	Low	Yes
Smart thermostat	Moderate	Yes (or fitter)
Annual boiler service	Moderate	Gas Safe engineer only
Loft insulation	Moderate	Often DIY

Typical savings by measure

The figures below are indicative ranges, last checked June 2026, drawn mainly from the Energy Saving Trust and Nesta. They assume a typical Great Britain household and will rise or fall with the current Ofgem price cap and your own usage — treat them as a guide, not a quote.

Measure	Indicative saving / year*	Rough cost
Thermostat down 1°C	~£80–£100 (≈10% off heating)	Free
Flow temperature 80→60°C	~£100 (≈6–9% of gas)	Free
Full heating controls (programmer + thermostat + TRVs)	~£110	Moderate
Hot-water cylinder jacket (80mm)	~£40	~£18
Radiator reflector panels (uninsulated external walls)	~£25	~£13/roll
Hot-water pipe lagging	~£6	A few £

*Indicative, last checked June 2026, for a typical Great Britain household on the July–September 2026 Ofgem cap. Savings don't simply add up — measures overlap — and your real figure depends on your home, tariff and habits.

Where boiler cover fits in

Reducing your gas bill is about efficiency; boiler cover is about protecting yourself from the cost of a breakdown. The two work together — many cover plans include an annual service, which keeps the boiler efficient and helps you avoid surprise repair bills.

If you're weighing it up, our explainer on whether boiler cover is worth it walks through the trade-offs.

This article is general information, not financial or technical advice. We compare a selected panel of providers, not the whole market, and may earn a commission if you buy through our links.