Mains gas
Mains gas is still the cheapest kWh for the typical UK household, but the price cap is not the deal — it’s a safety net. Fixed tariffs from challenger suppliers regularly undercut it by 8–14%, and the standing charge is where switchers save most.
This week's best deals
Rates indicative. Confirm with supplier before ordering.
Octopus Energy
4.8Top-rated service, smart-meter tariffs
OVO Energy
4.3Rewards for reducing usage
E.ON Next
4.2Renewable-matched electricity
British Gas
3.9Boiler cover included
Some supplier links may pay us a commission if you switch. It never changes the price you pay.
Why homeowners choose it
- Lowest running cost per kWh for most homes
- Widest supplier choice — ~20 active retailers
- Gas boilers still dominate UK housing stock
Trade-offs to weigh up
- Ofgem cap adjusts every three months — budgeting is hard
- Standing charges apply even when you use nothing
- Exposed to international wholesale price shocks
Three tips from the mains gas desk
Fix when caps look low
If a fixed tariff is within 3% of the current cap, lock it. Wholesale markets are volatile and a winter cold snap routinely pushes the next cap upwards.
Scrutinise the standing charge
A 30p/day charge is £109/year before you burn a single cubic metre. Compare headline unit rates alongside standing charge to find the real winner.
Submit a meter reading before switching
Taking a photo of the meter the day you switch protects you from estimated final bills — the single biggest post-switch complaint.