How to Reduce Your Heating & Gas Bill
Turn your thermostat down by 1°C, the Energy Saving Trust estimates that alone can cut your heating bill by up to about 10%. Lower your combi boiler's flow temperature, bleed and reflect your radiators, and draught-proof doors and windows (around £125 a year). Only heat the rooms you use, and set the heating to a timer rather than leaving it on all day. None of these cost much, most cost nothing.
In this post, we'll cover
Key takeaways
- 1°C off the thermostat can save up to ~10% of your heating bill (Energy Saving Trust).
- Lowering a combi boiler's flow temperature can make it run more efficiently.
- Draught-proofing is cheap, quick and one of the best-value first jobs.
- Radiator reflector panels and bleeding trapped air help heat reach the room, not the wall.
- Heating on a timer beats heating on all day, warm the home around your routine.
- An annual boiler service keeps it efficient and safe, so it burns less gas doing the same job.
If you only tackle one bill, make it this one. Heating and hot water dominate most households' energy use, so a handful of sensible changes here move the needle more than anything else you can do.
The best part: the biggest heating savings are the cheapest. You can make most of the changes below this weekend, for little or no money.
1. Get your thermostat and controls right.
Your thermostat is the most powerful money-saving dial in the house. The Energy Saving Trust's long-standing rule of thumb is that turning it down by just 1°C can cut your heating bill by up to around 10%, and most people won't notice the difference in comfort. Somewhere around 18–21°C suits most homes; find the lowest setting that still feels comfortable and leave it there.
Just as important is when the heating runs. Use the timer or a programmable/smart thermostat to warm the house around your actual routine, up before you wake, off before you leave, on again before you're home, rather than heating an empty house all day. A smart thermostat that learns your schedule or senses when you're out can trim this further.
Tip: Turn down rooms you don't use. Thermostatic radiator valves (TRVs) let you set each room individually. Turn them down in spare rooms and hallways you rarely sit in; there's no sense paying to heat a room to the same temperature as your living room when nobody's in it.
2. Turn down your boiler's flow temperature
This one's less well known and it's free. If you have a combi boiler, the “flow temperature” is how hot it heats the water it sends to your radiators, and many are set higher than they need to be. Turning the flow temperature down (a common target for condensing combis is around 60°C or lower for the heating circuit) helps the boiler run in its efficient “condensing” mode, so it burns less gas to keep you just as warm.
It's a dial or setting on the boiler itself, separate from your room thermostat. If you're not sure how to adjust it safely, your boiler manual or a heating engineer can point you to the right control. Your rooms may take a little longer to reach temperature, but the efficiency gain is worth it.
3. Get more heat out of your radiators
Radiators quietly under-perform for two common reasons, and both are easy fixes:
- Bleed trapped air: If a radiator is cold at the top but warm at the bottom, air is trapped inside. Bleeding it (with a radiator key, heating off) lets the whole surface heat up again, so you get the warmth you're already paying for.
- Fit reflector panels on external walls: Radiators on outside walls send a chunk of their heat straight into the wall. A reflective panel behind them bounces that heat back into the room, cheap, and especially worthwhile in older, less-insulated homes.
- Keep them clear: Don't drape washing over radiators or block them with furniture and long curtains, it stops warm air circulating and pushes your heating to work harder.
4. Draught-proof and stop heat escaping
Draughts are money leaking out of your home. Unless it's very new, your home loses heat around doors, windows, letterboxes, keyholes, loft hatches and gaps in floors and skirting. The Energy Saving Trust puts typical draught-proofing savings at around £125 a year, and DIY foam strips and brush seals cost very little.
- Cheap draught fixes that punch above their weight:
- Self-adhesive foam or brush strips around door and window frames.
- A letterbox flap and keyhole cover.
- A draught excluder along the bottom of external doors.
- Sealing gaps around skirting boards and floorboards.
5. Insulation: the bigger, longer-term win
Behavioural changes are free; insulation costs money but pays back for years. A large share of a home's heat escapes through the roof and walls, so loft insulation and cavity wall insulation are usually the highest-value structural upgrades. The Energy Saving Trust estimates meaningful annual savings from both, depending on your property.
Because the upfront cost is real, check whether you qualify for help first: government schemes such as the Great British Insulation Scheme and ECO support can fund insulation for eligible households. It's worth checking your eligibility before paying full price.
6. Everyday habits that add up
Small routines, repeated all winter, quietly lower the bill:
- Close curtains at dusk to keep heat in, but don't cover radiators.
- Close doors to keep heat in the rooms you're using.
- Layer up before you reach for the thermostat.
- Service your boiler yearly so it runs efficiently and safely.
- Consider your hot-water cylinder jacket and pipe lagging if you have a hot-water tank.
Savings at a glance
Indicative estimates from the Energy Saving Trust for a typical home. Your savings depend on your property, habits and current energy prices, which change over time.
- Thermostat down 1°C: up to ~10% of heating bill (free).
- Draught-proofing: around £125/year (low cost, cheaper if DIY).
- Radiator reflectors & bleeding: small but adds up (low cost).
- Lower combi flow temperature: improves boiler efficiency (free).
- Loft & cavity wall insulation: significant, property-dependent (higher cost, grants may help).
A note on the numbers: Pound figures for energy savings move up and down with the price cap and your supplier's rates, so treat them as a guide to what's worth doing rather than a fixed promise. The percentages and the priorities (heating first, then draughts and insulation) stay reliable even as prices shift.
An efficient boiler is a cheaper boiler.
A boiler that's serviced and running well burns less gas, and won't leave you with a shock repair bill when it fails. Smart Cover'sboiler and central heating coverkeeps your heating maintained and gets an engineer to you fast when something goes wrong.
Smart Cover protects your heating system from breakdown. It isn't an energy supplier.
Disclaimer
- This guide is general information for UK households and is not financial or professional heating advice. Savings figures are indicative estimates from the Energy Saving Trust for a typical home and vary with property, usage and energy prices. Always follow your boiler's instructions and use a Gas Safe registered engineer for gas work. Smart Cover is a provider of home emergency and appliance cover, not an energy supplier. Cover levels, limits and exclusions vary by plan, see your policy documents and IPID.
- Smart-Cover Direct Limited (FRN 600428) is an Appointed Representative of City and Commercial Limited (FRN 314346), which is authorised and regulated by the Financial Conduct Authority. Registered office: Ashley Court, 32 Main Street, Ashley, Market Harborough, Leicestershire, LE16 8HF. Principal place of business: Citibase, 42-44 Clarendon Road, Watford, WD17 1JJ.
