If your central heating system is old, inefficient, or broken, you could get it replaced for free under ECO4 or heavily subsidised through the Boiler Upgrade Scheme. ECO4 covers the full cost for eligible low-income households, while BUS knocks £7,500 off a heat pump installation. Your options depend on what you currently have, your EPC rating, and your household income.
What Type of Central Heating System Do You Currently Have?
This matters more than most people realise. The grants available to you, the upgrade path that makes sense, and the cost you'll face all depend on what's currently heating your home.
Most UK homes run on a gas boiler connected to radiators via a wet central heating system. If that's you, your boiler heats water, pumps it through pipes to your radiators, and the radiators warm your rooms. Simple enough. But around 4 million homes don't have mains gas at all, and they're running on oil, LPG, electric storage heaters, or in some older properties, solid fuel systems like coal or wood.
Check if you qualify
Answer a few quick questions to see which government energy grants you're eligible for. Free, instant results.
Here's why this matters for grants: homes without mains gas are prioritised by almost every funding scheme. If you're on oil or LPG, you're actually in a stronger position for a funded heat pump than someone with a relatively modern gas combi boiler.
So what's your system? Roughly:
Gas combi boiler (no hot water tank, heats water on demand)
Gas system or regular boiler (has a hot water cylinder, possibly a tank in the loft)
Oil boiler (external oil tank, usually in rural areas)
LPG boiler (gas bottles or a bulk tank)
Electric storage heaters (charge overnight on Economy 7, release heat during the day)
Warm air systems (ducted heating, common in 1960s-70s builds)
If you're not sure, check your EPC. It lists your heating system type. And if you don't have a current EPC, here's what one costs and why it's worth getting before you apply for anything.
Which Grants Can Help Cover the Cost of a New Central Heating System in 2026?
Right, this is what you're here for.
Two schemes are doing the heavy lifting for central heating upgrades right now. They work very differently, cover different people, and can't be combined on the same measure, so let's be clear about which one applies to you.
ECO4
ECO4 is the one that can fund your entire central heating system at no cost to you. It's open until December 2026 and targets low-income households in poorly insulated homes. If you receive benefits like Universal Credit, Pension Credit, Child Tax Credit, or Income-based JSA, and your home has an EPC of D or below, you're likely eligible.
The scheme doesn't just cover boiler replacements. It funds first-time central heating installations (if you've never had a proper system), heat pumps, insulation, and sometimes a combination. We've covered the full eligibility criteria in our free boiler scheme guide, which walks through exactly who qualifies and how to apply.
One thing most guides won't tell you: ECO4 is delivered by energy suppliers, and each supplier has different priorities. Some are actively funding first-time central heating in rural homes. Others are focused on insulation. The installer you go through matters enormously because they determine which supplier's obligation they fulfil.
Boiler Upgrade Scheme (BUS)
This one's simpler but narrower. BUS gives you a flat £7,500 off an air source heat pump or ground source heat pump, £5,000 off a biomass boiler, or £2,500 off an air-to-air heat pump or heat battery. It's open until March 2028.
No income test. No benefits requirement. But you do need a valid EPC with no outstanding loft or cavity wall insulation recommendations, and the property must not currently be on the gas grid if you're claiming for biomass. For heat pumps, gas-connected homes are eligible.
The catch? Even with £7,500 off, you're still paying £4,000 to £7,000 out of pocket for a typical air source heat pump installation. That's not nothing. We'll get into the full cost breakdown below.
Warm Homes: Local Grant
This varies wildly by council area. Some local authorities are offering funded heating upgrades, others are focused entirely on insulation. The scheme runs until December 2028 and the amounts depend on where you live and what your local authority has decided to prioritise. Check your council's website or read our full guide to the Warm Homes: Local Grant for how to find your area's specific offer.
How Much Does It Cost to Upgrade or Replace a Central Heating System?
£2,500 to £15,000. That's the honest range, and it's wide because "central heating system" covers everything from swapping a boiler to ripping out storage heaters and installing a complete wet system from scratch.
Here's what we typically see:
Upgrade type
Typical cost (2026)
Notes
Gas boiler replacement (like-for-like)
£2,500–£4,500
Combi swap, existing pipework
Gas boiler + new radiators
£4,000–£7,000
Older systems needing full refresh
First-time central heating (no existing system)
£5,000–£9,000
Pipework, radiators, boiler, controls
Air source heat pump
£11,000–£15,000
Before BUS grant
Ground source heat pump
£20,000–£35,000
Before BUS grant
Biomass boiler
£10,000–£19,000
Before BUS grant
Those heat pump figures look alarming. But after the £7,500 BUS grant, an air source heat pump comes in at £4,000 to £7,500, which isn't dramatically more than a full gas system replacement with new radiators. And if you're on oil or LPG, the running cost savings close the gap within 5-7 years in most cases.
Heat Pumps vs Gas Boilers: Which Central Heating System Is Right for Your Home?
Honestly, this one depends on your situation and we can't give you a straight answer without knowing your home. But here's how we'd think about it.
Stick with gas if:
Your current boiler is broken and you need heat urgently (heat pump installations take weeks to arrange)
Your home is poorly insulated and you're not ready to address that yet
You have very small rooms where larger heat pump radiators won't physically fit
You're planning to sell within 2-3 years and want minimal disruption
Go for a heat pump if:
You're off the gas grid (oil and LPG are expensive, and you'll qualify for BUS)
Your home is reasonably well insulated, say EPC band D or above
You're eligible for ECO4 or BUS funding
You're staying long-term and want to lock in lower running costs as gas prices rise
Here's the honest bit. A heat pump in a draughty, uninsulated Victorian terrace will struggle. It'll run constantly, your bills won't drop, and you'll be cold. But a heat pump in a well-insulated 1990s semi? That's a different story entirely. The insulation comes first. Always.
One tangent worth mentioning: hybrid systems exist. A heat pump handles most of your heating, and a gas boiler kicks in on the coldest days. They're not covered by BUS (the grant requires a full fossil fuel replacement), but some ECO4 installations have included them. Anyway.
How to Check If You Qualify for a Funded Central Heating System
Two routes. Both start with your EPC.
If you don't have one, get one. They cost £60 to £120 and take about 45 minutes. Your EPC rating determines which schemes you can access. A D rating or below opens up ECO4. Any rating works for BUS, provided you've addressed any recommended loft or cavity insulation. Here's what each EPC band means for grants.
For ECO4, you need to be receiving a qualifying benefit AND have a home rated D, E, F, or G. The process goes through an installer who handles the application to the energy supplier. You don't apply to a government website directly.
For BUS, you need an MCS-certified installer to submit the application on your behalf. They apply for the voucher, and the £7,500 (or £5,000 for biomass) comes off your invoice. You never see the grant money yourself.
The simplest first step? Check your eligibility through our tool. Two minutes, no commitment, and you'll see exactly which schemes apply to your home.
How to Get the Most Out of Your Central Heating System After an Upgrade
So you've got a new system. Now what?
If you've had a heat pump installed, your heating habits need to change. Heat pumps work best running at a lower temperature for longer periods, not the blast-it-for-an-hour approach that works with gas boilers. Set your flow temperature to around 35-45°C (your installer should configure this) and let the system maintain a steady warmth rather than cycling on and off.
Insulation amplifies everything. Even after a new system goes in, adding loft insulation or addressing wall insulation makes your new heating work less hard, which means lower bills and a longer system lifespan.
Three quick wins that cost nothing:
Turn your boiler flow temperature down to 55°C if you're on a condensing gas boiler. Most are set to 70-80°C from the factory, which wastes energy and stops the boiler condensing properly.
Bleed your radiators annually. Trapped air means cold spots and wasted energy.
Use your programmer properly. Heating an empty house for 8 hours while you're at work is just burning money.
And look, if your walls and loft are already sorted, consider whether your windows are the weak link. Our guide to window grants covers what funding exists for glazing upgrades in 2026.
The system is only half the equation. The fabric of your home determines whether that heat stays inside or leaks straight out through the walls and roof. Get the envelope right, and even a modest heating system keeps you comfortable.
This article contains affiliate links. If you request quotes through our links, we may receive a commission at no extra cost to you. This helps keep Eco Home Check free and independent. How we earn
Grant amounts and eligibility criteria are based on publicly available government data and may change. Always verify current terms directly with the scheme provider.
Frequently asked questions
Can I get a completely free central heating system in the UK?
Yes, but only through ECO4. If your household receives qualifying benefits (Universal Credit, Pension Credit, Child Tax Credit, or similar) and your home has an EPC rating of D or below, you can get a full central heating system installed at no cost. This includes first-time installations in homes that have never had central heating. The scheme runs until December 2026.
Do I need to replace my gas boiler with a heat pump?
No. Nobody is being forced to replace a working gas boiler. The government's grants incentivise heat pumps, but if your boiler breaks down, you can still install a new gas boiler without any penalty. The 2035 gas boiler ban applies to new-build homes, not existing ones.
How long does it take to install a new central heating system?
A like-for-like gas boiler swap takes 1-2 days. A full central heating installation with new pipework and radiators takes 3-5 days. Heat pump installations typically take 2-4 days for the unit itself, but the whole process from survey to commissioning can stretch to 6-8 weeks because of the MCS certification paperwork, the BUS voucher application, and scheduling. If you need heat urgently in winter, a heat pump isn't a quick fix.
Will a heat pump work in an older house?
It depends entirely on insulation. A well-insulated older home, yes, absolutely. A draughty Victorian terrace with single glazing and no wall insulation? You'll struggle. The general rule is: insulate first, then install a heat pump. Most MCS installers will do a heat loss calculation and tell you honestly if your home needs work before a heat pump makes sense.
Can I combine ECO4 and the Boiler Upgrade Scheme?
Not on the same measure. You can't use both schemes to fund one heat pump. However, you could potentially use ECO4 for insulation and then apply for BUS for the heat pump separately, provided you meet the eligibility criteria for both. This is actually a smart strategy if you qualify.