If you are comparing a heat pump vs gas boiler, the first thing to know is that there is no one-size-fits-all answer. In the UK, a heat pump is much more efficient on paper, but that does not always mean it will be cheaper to run in every home. Electricity still costs far more per kWh than gas under the current Ofgem price cap, which changes the maths quite a bit. Between 1 April and 30 June 2026, the average Direct Debit price cap rates are 24.67p per kWh for electricity and 5.74p per kWh for gas.
At Willow Services, we help homeowners, landlords, and property managers make sense of these choices in real-world terms, not just headline claims. We install air source heat pumps and boilers, and we also support customers with wider heating needs across Peterborough and beyond. Our team is Gas Safe registered, Baxi registered, G3 Unvented qualified, and all our work comes with at least a one-year guarantee.
So, when people ask us, “Which is cheaper to run in the UK?” our honest answer is this: a modern gas boiler is often still cheaper or very similar to run on standard tariffs, while a heat pump can become very competitive or even cheaper in the right property and tariff setup. The better system depends on your insulation, radiators, hot water demand, age of boiler, and whether you are looking only at running costs or at the wider picture as well.
Running Costs: Heat Pump vs Gas Boiler in Simple Terms
To understand running costs, it helps to strip the comparison back to heat output.
A modern gas boiler with around 90% efficiency uses gas to create heat, so you are paying the gas unit rate and losing a small percentage in the process. A heat pump uses electricity, but because it moves heat rather than generating it directly, it can deliver around three units of heat for every unit of electricity used. Energy Saving Trust says heat pumps can deliver three to four times as much heat per unit of electricity, compared with an A-rated boiler at around 90% efficiency.
Using the current average Ofgem cap rates, gas is 5.74p per kWh and electricity is 24.67p per kWh.
That means:
A Modern Gas Boiler
Even with strong efficiency, gas still starts from a much lower unit price, so it remains hard to beat on raw fuel cost alone on gas boilers.
An Efficient Heat Pump
A heat pump can offset expensive electricity through much higher efficiency, which is why it can end up surprisingly close to a gas boiler on running costs in the right home.
In other words, the gap is not as wide as the electricity price suggests, but the heat pump is not automatically cheaper either.
When a Gas Boiler is Often Cheaper to Run
In many existing UK homes, especially those already connected to mains gas, a modern condensing boiler remains a very cost-effective heating option. That is particularly true when the home already has a boiler-friendly setup, strong hot water demand, and no appetite for upgrading emitters or insulation.
At Willow Services, we often find a gas boiler makes the most financial sense when:
The Property Already Uses Mains Gas
If the home is already built around a gas heating system, replacing an ageing boiler with a newer efficient model is often the most direct and affordable route. Our own guidance notes that for properties already connected to the gas grid, upgrading to a high-efficiency boiler is often the simplest way to improve comfort and reduce bills.
The Current Boiler is a Bit Old and Inefficient
If you are moving from a 10 to 15-year-old boiler to a modern condensing unit, the savings can be meaningful without changing the whole heating system. Willow Services’ published guidance highlights that many modern condensing gas boilers operate at over 90% efficiency, and that replacing an unreliable older unit can lower monthly heating bills. If you are open towards a boiler upgrade or inspection, there are professionals that offer such services for your heating system.
The Property has High Hot Water Demand
Families and larger households often value the fast, familiar hot water performance that a gas boiler can provide, especially in different climate conditions. That can be a practical advantage, not just a comfort preference.
You Want Lower Upfront Disruption
A boiler replacement is often simpler and less disruptive than moving to a completely different heating system, especially in older housing stock.
Suggested Reading: Finding Reliable Boiler Fitters Near You: A Complete Guide
When a Heat Pump can be Competitive or Cheaper
A heat pump starts to look much stronger when the property is well suited to low-temperature heating and when you look beyond just the unit price of electricity.
A heat pump can be a very good fit when:
The Home is Well Insulated
Heat pumps work best in homes that hold onto heat efficiently. Energy Saving Trust says air source heat pumps are suitable for most types of homes, but homeowners should consider whether the property is right for the system before deciding.
The System is Properly Designed
A heat pump is not something we believe should be fitted on a guess. Correct sizing, flow temperatures, emitter selection, and commissioning all matter. A poorly designed system can wipe out the efficiency advantage that makes a heat pump attractive in the first place.
You are on, or Can Access, a More Suitable Tariff
Specialist heat pump tariffs can make a major difference. Which? notes that heat pumps can currently be more expensive to run than gas boilers on standard capped electricity, but adds that some suppliers now offer specialist tariffs that can significantly reduce the electricity cost used to operate a heat pump.
You are Replacing Something Worse than a Modern Gas Boiler
Energy Saving Trust says an air source heat pump can save money depending on the system you are replacing, and that heat pumps lower energy use because they are much more efficient than traditional boilers.
Suggested Reading: Why Professional Heating Systems Installation and Maintenance Saves You Money
So Which is Cheaper to Run in the UK right now?
A modern gas boiler is still often the cheaper and safer option for most homes on a standard tariff, especially if the property already has gas, the boiler is being upgraded rather than added from scratch, and the home is not ideal for low-temperature heating.
A heat pump can be just as cheap to run, or sometimes cheaper, in a well-insulated property with the right design and tariff, but it should not be sold as an automatic money-saver in every UK home. Energy Saving Trust explicitly says not everyone who installs a heat pump will see savings straight away, especially if they are replacing a much newer and more efficient gas boiler.
Our view at Willow Services is simple: if you want the honest answer, the cheaper system to run depends on the house as much as the hardware.
Our Advice at Willow Services
We do not believe in pushing one heating technology for every property. At Willow Services, we install both boilers and air source heat pumps because different homes need different answers. We support local residents, agents, and landlords, and we bring over 40 years of experience across boilers, central heating, plumbing, and heat pumps. Our team is fully Gas Safe registered for boilers and gas work, we are a Baxi Registered Installer, and we provide at least a one-year guarantee on all completed work.
If your home is already on mains gas and you want a reliable, lower-disruption upgrade, a boiler may still be the best-value route. If your property is well insulated and you want to invest in lower-carbon heating, an air source heat pump may be the better long-term choice.
The important thing is not choosing the system with the biggest headline. It is choosing the one that suits your property, budget, and expectations.
Suggested Reading: Why Cambridge Chooses Willow Services for Heat Pumps
FAQs
Is a heat pump always cheaper to run than a gas boiler in the UK?
No. Heat pumps are much more efficient, but electricity is currently much more expensive than gas, so running costs can be similar or sometimes higher depending on the home and tariff.
Are gas boilers still a good option in 2026?
Yes. Gas boilers remain a practical and common option for many UK homes, especially those already connected to mains gas.
Do heat pumps work well in UK homes?
Yes, they can. Energy Saving Trust says air source heat pumps are suitable for most types of homes, but proper assessment and design are important.
Can I get a grant for a heat pump?
In England and Wales, the Boiler Upgrade Scheme currently offers £7,500 towards an air source heat pump for eligible properties.
Does Willow Services install both boilers and heat pumps?
Yes. We provide support for both boiler installations and air source heat pumps, along with wider heating and plumbing services.
Speak to Willow Services about the right heating option
If you are weighing up a heat pump vs gas boiler and want practical advice based on your property, we are here to help. At Willow Services, we can assess your current setup, explain the likely running-cost picture, and recommend the option that makes the most sense for your home or rental property.
Call us today at 01733590501 or send us an email at james@willowservices.co.uk to get in touch with our team.