Mark RobertsThe Ofgem energy price cap jumped 13.5% on 1 July 2026, pushing a typical UK dual-fuel bill to £1,862 a year — the highest since the energy crisis of 2022. With wholesale gas prices spiking on the back of Middle East supply disruptions, millions of homeowners are now asking the same question: should they patch an ageing boiler one more time, or act now while Government grants are still on the table?
Why Your Gas Bill Is the Highest It's Been in Years
The July surge comes down to LNG (liquefied natural gas) supply tightening on global markets. The UK sources roughly one third of its energy from LNG, and ongoing tensions linked to the US-Iran standoff have restricted key supply corridors. Because gas-fired power stations still set the marginal price of electricity on the grid on most days, rising gas costs drag electricity up with them — a mechanism the House of Commons Library has repeatedly flagged as a structural vulnerability in UK energy pricing.
The average UK gas bill as of July 2026 stands at £696.35 per year before the standing charge, according to Ofgem data. The price cap is reviewed quarterly, and while forecasters expect a modest easing into late 2026 and 2027, wholesale markets remain volatile enough that no analysts are guaranteeing a significant fall before winter.
For homeowners whose boiler is already approaching the end of its useful life — roughly 15 years for a modern combi — the timing question is no longer hypothetical. Every additional year spent heating an inefficient system costs money that can be recovered through a planned upgrade.
The Warm Homes Plan Changed the Equation — Here's What It Means
When the Government published the Warm Homes Plan on 20 January 2026, it officially abandoned the proposed 2035 ban on new gas boilers in existing homes. No homeowner is now required to replace a working boiler, and a new gas boiler remains a legal and available option if an existing one fails. The policy shift has been widely described as a "carrots not sticks" approach: rather than mandating low-carbon heating, ministers are using financial incentives to encourage voluntary switching.
The main incentive is the Boiler Upgrade Scheme (BUS), which currently offers a grant of up to £7,500 towards the cost of an air source heat pump installation. That figure represents a substantial portion of the total project cost for many properties, and — unlike previous iterations of the scheme — there is no confirmed end date for the current grant rates, meaning the window is open but not indefinite.
The Numbers: What Replacing Your Heating System Actually Costs in 2026
Understanding whether to repair, replace like-for-like, or switch to a heat pump requires a clear view of the figures involved.
Gas boiler replacement (like-for-like): A standard gas combi boiler replacement, including labour and parts, typically costs between £2,500 and £4,000. The new unit is expected to last 12–15 years and will likely be more efficient than the appliance it replaces — a modern A-rated combi can cut gas consumption by 15–20% compared to a pre-2010 boiler.
Air source heat pump (before grant): A full air source heat pump installation, including the unit, internal pipework adjustments, and commissioning, typically runs between £8,000 and £18,000 depending on property size and the condition of existing radiators.
Air source heat pump (after BUS grant): Applying the maximum £7,500 grant brings the net cost to between £500 and £2,500 for a straightforward installation in a suitable property — in some cases, cheaper than a new gas boiler.
Long-term operating cost difference: At 2026 energy tariffs, air source heat pump running costs are broadly comparable to a modern gas boiler on a standard deal. Over a 20-year horizon, however, a heat pump is projected to save approximately £3,900 versus gas, based on current price trajectories and the expected decarbonisation of the electricity grid.
A Concrete Case: The Ageing Boiler in a North London Terrace
Consider a homeowner in North London with a 15-year-old gas combi that has needed annual repairs for the past three years, at an average call-out and parts cost of £480 per visit. Their total dual-fuel bill under the current price cap runs to approximately £1,400 per year, with gas accounting for around £700.
If they repair again this winter: Another £480 to £600 repair pushes their cumulative repair spend over three years beyond £1,800 — with no reduction in their ongoing gas bill and no certainty the boiler survives another winter intact.
If they replace like-for-like with a new gas combi: Upfront cost of around £3,200. Annual gas bill falls to approximately £595 thanks to higher efficiency, saving roughly £105 per year. Break-even on the investment versus continued repairs: approximately 10 years — or sooner if the old boiler would have failed entirely.
If they apply for the BUS grant and install an air source heat pump: Gross installation cost of £13,500, minus the £7,500 BUS grant, equals a net cost of £6,000 (their property requires some radiator upgrades to handle lower-flow-temperature heating). Running costs at 2026 electricity prices are comparable to their current gas bill, but the long-term trajectory favours the heat pump as electricity decarbonises. Over 20 years, the projected saving versus staying on gas is approximately £3,900. Break-even on the net investment: roughly 8–10 years, falling to 5–6 years if electricity tariffs fall relative to gas as forecast.
The right answer for this homeowner depends on factors a comparison website cannot provide: their EPC rating (the BUS grant requires a D rating or above), the condition of their radiators, and their expected tenure in the property. That is precisely the kind of cost-benefit modelling a home improvement specialist can provide.
What to Check Before You Decide
The route that makes financial sense varies by property. Before speaking to any installer, it's worth gathering four pieces of information.
Your boiler's age and service history. Any boiler over 12 years old that has needed two or more repairs in the past three years is statistically more likely to fail within the next 12 to 24 months. A Gas Safe-registered engineer — the legal requirement for any work on a gas appliance in Great Britain — can give a condition assessment without committing you to a replacement.
Your EPC rating. The BUS grant requires your home to have an Energy Performance Certificate rating of D or above. If your certificate is more than 10 years old, request an updated assessment. An EPC assessor can also identify insulation improvements that reduce the total size of heat pump you need, cutting installation costs.
Your radiator and pipework capacity. Heat pumps operate at lower flow temperatures (typically 45–55°C versus 70–80°C for a gas boiler), which means oversized or upgraded radiators are often needed. An MCS-certified installer can survey your existing system and quote for any necessary upgrades.
Your tariff situation. If your current energy deal expires before the price cap falls, a short-term fixed tariff — even slightly above the cap — may offer predictability worth paying for over the winter months. As rising energy bills continue to affect UK households, support schemes including Warm Home Discount and expanded Cold Weather Payments have also been widened for 2026 — worth checking eligibility before winter.
Three Actions Worth Taking Before October 2026
Get your existing boiler serviced now. An annual gas boiler service costs £80–£120, is recommended annually by manufacturers, and is a legal requirement for landlords in rental properties. A service in August or September catches problems before they become failures in the coldest months.
Request MCS-certified quotes for a heat pump if your home is EPC D or above. The BUS grant has no advertised closing date, but grant budgets have been cut before — and installation lead times across UK heating trades are currently running at 6–10 weeks for air source systems.
Speak to a home improvement expert about your specific property. Generic comparison sites model average homes. A specialist adviser can run the numbers on your actual EPC rating, radiator configuration, hot water demand, and local installer pricing — and tell you whether a heat pump makes financial sense or whether a like-for-like gas boiler replacement is the smarter near-term move.
Important: The figures in this article are based on Ofgem price cap data and BUS grant rates as of August 2026. Individual installation costs vary by property size, insulation level, regional labour rates, and installer availability. Always obtain written quotes from Gas Safe-registered engineers (for gas work) or MCS-certified installers (for heat pumps) before committing to any heating upgrade.
Gas bills are not falling fast enough to make waiting a neutral choice. Whether the right answer for your property is a repair, a like-for-like replacement, or a switch to a heat pump, an expert on ExpertZoom can give you the tailored analysis your heating decision deserves.
