How many heat pump installer quotes should I get?

The number matters because a heat pump is a designed system, not a box swapped for a boiler. Government guidance puts it plainly: get at least three installers to quote "so that you can compare costs and design"⁷. Two quotes tell a household what the work costs. Three begin to show where installers disagree about what the work is.

Why three quotes, and what the comparison is actually for

Three is not a ritual. It is the smallest number that exposes a difference. With one quote, a household sees a price and a proposed system. With three, it sees three heat loss calculations, three proposed flow temperatures, three emitter specifications and three prices for broadly the same house. The variation between them is the information.

The reason design varies so much is that heat pumps perform differently from combustion boilers. Which? describes a heat pump with a COP of 3.0 as producing three times more heat energy than the electrical energy it consumes, and notes that heat pumps typically deliver three to four units of heat for each unit of electricity¹¹. Government guidance states that heat pumps are now typically more than three times as efficient as a gas boiler¹². Those figures are the reason a heat pump can heat a home at all, and they are also the reason sizing and emitter design matter: a system designed around a lower flow temperature needs larger emitters, and a system designed around a higher one may not reach the efficiency the household expected.

That is what the three quotes are testing. An installer who has calculated the heat loss properly will propose a system size and a flow temperature that follow from the calculation. An installer who has not will propose something that looks similar on paper and behaves differently in January.

The same three-quote recommendation appears in guidance on heating controls, which recommends quotes from at least three different installers "to make sure you're getting value for money"⁴. Northern Powergrid's installation guidance for renewable energy systems says to talk to more than one installer and obtain at least three quotes⁵. The figure is consistent across official, independent and network operator guidance, which is unusual and worth noting.

What to check: MCS certification and qualifications

The certification to look for is MCS. The Energy Saving Trust's moving-house checklist includes the instruction to check whether the heat pump has an MCS certificate, and the installation guide specifies MCS-certified installers rather than installers generally². Independent guidance on choosing an installer states the same requirement: choose an MCS-certified heat pump installer¹⁴.

MCS certification is not a badge of quality in the abstract. It is the route by which a heat pump becomes eligible for the Boiler Upgrade Scheme. Official guidance for installers under that scheme states that installers must be MCS certified and certified to install heat pumps and/or biomass boilers¹⁵. A household that uses a non-certified installer may find the installation cannot be grant-funded, and may find the metering information that Ofgem requires cannot be added to an MCS certificate¹⁶.

There is a second layer of qualification that applies to the building work rather than the product. Official guidance for Wales sets out that, before work begins, an installer not registered as a competent person must either notify the local authority or arrange for a registered building control approver to oversee the work¹⁷. That is a Welsh position and the devolved building regulations differ, so a household in England, Scotland or Northern Ireland should expect the equivalent requirement to be framed differently. The practical point is the same: ask which competent person scheme the installer belongs to, and expect the answer to be specific.

How long it takes: booking delays of a few weeks

The quote process has its own lead time, separate from the installation. One documented case study of a household replacing storage heaters with an air source heat pump reports that booking installers to quote took a few weeks⁸. That is the period between deciding to get quotes and having three installers in the house, and it is worth building into any timetable.

The installation itself is shorter than most households expect. Independent guidance states that the installation typically takes around three days, though it may take longer depending on the property². The gap between the two figures, a few weeks to quote and three days to install, is where most of the elapsed time in a heat pump project sits.

There is a third delay that applies to some installations only. Independent guidance notes that some installations may need approval from a distribution network operator, which can add a delay of up to 12 weeks⁹. Separate guidance puts the average approval time for a heat pump installation at between 2 and 4 weeks under different DNOs¹⁰. Those two figures describe different things: a typical approval and a worst case. Where an installation needs a supply upgrade, the DNO process runs alongside the installer's work rather than after it, but it can still set the earliest date the system can be commissioned.

What a quote should cover: design, heat load and controls

A quote that gives a price and a model name is not enough to compare. Official guidance on new dwellings sets out what operating and maintenance information provided to the dwelling owner should include: the heat loss calculation, the design flow temperature, confirmation of the competent person scheme, the size of the emitter circuit, and minimum set back temperatures¹⁷. Those five items are a reasonable checklist for what a quote should contain, even though the requirement is written for new build.

The heat loss calculation is the foundation. Independent guidance describes installers calculating the home's heat demand and other information to inform their recommendations². Without that calculation, the proposed system size is an estimate, and the household has no way to tell whether two installers proposing different sizes are disagreeing about the house or about the method.

Controls belong in the quote rather than in a separate conversation. Independent guidance recommends quotes from at least three different installers for heating controls work⁴, which implies controls are quoted as part of the job. Design flow temperature and minimum set back temperatures are control settings as much as design decisions, and both appear in the official list of information the owner should receive¹⁷.

Metering is the fourth item, and it is easy to overlook. Ofgem's guidance for the Domestic Renewable Heat Incentive sets out heat meter counts by system type: one heat meter for a heat pump with a two-pipe output, two for a four-pipe or three-pipe output or a bivalent system with a two-pipe heat pump, and three for a bivalent system with a four-pipe or three-pipe heat pump, with fewer meters permitted where the manufacturer has integrated metering¹⁸. A household that wants to monitor performance, or that is claiming a grant, needs to know which arrangement is being quoted.

When three is not enough: hybrid and complex systems

Three quotes is a floor, not a target. Where the system is more complex, or where the market offers more combinations, more quotes give a household more to compare.

Hybrid systems are the clearest case. Official guidance on domestic hybrid heat pumps notes that there are three packaged solutions on the UK market alongside a large number of add-on hybrid heat pumps¹⁹. A packaged hybrid is a defined combination of heat pump and boiler; an add-on hybrid is assembled from parts. Those two categories are not quoted on the same basis, and a household comparing a packaged system against an add-on system is comparing different things unless the quotes make the distinction explicit.

The performance case for hybrids rests on how much of the heating load the heat pump carries. Independent guidance states that, by using a hybrid, 80% of the space heating demand is delivered by a technology that is around three times more efficient²⁰. It also notes that smaller heat pumps require a lower electrical demand, often with only a 6 to 10 amp mains supply necessary²⁰. That lower electrical demand is one of the practical reasons a hybrid is specified, and it is a design point that should appear in the quote.

Complexity also shows up in noise assessment. The MCS 020 calculator supports assessments for one, two and four heat pumps, with four assessment positions per assessment, and requires the make and model and installation location for each unit²¹. A property needing more than one outdoor unit, or a bivalent system, is a more involved design, and the quote should reflect that work rather than treat it as a single-unit job.

There is a knowledge gap that bears on how many quotes a household may need. Official statistics from the winter 2025 public attitudes tracker report that around a third of owner-occupiers said they did not know enough about each system to make a decision, with 30% saying so for air source heat pumps and 38% for hybrid heat pumps²². Which? reports a third of homeowners thinking the technology would not be good enough to heat their homes²³. More quotes, and more detailed quotes, are one way a household closes that gap before committing.

What to compare between heat pump quotes

Comparing quotes means comparing the same items across all of them. The table below sets out what to look for and where the requirement comes from.

The comparison is not only about price. Two quotes can arrive at the same total through different routes: one specifying a larger heat pump and smaller emitters, another a smaller heat pump and larger emitters. Both may work. Only the heat loss calculation shows which is sized to the house.

What this means for a household's energy independence

A heat pump moves a home's heating off gas and onto electricity, which changes where the dependence sits rather than removing it. The household still relies on the grid, on an electricity supplier, and on the manufacturer for parts and, in many cases, for controls that connect to an app or a cloud service. What changes is the fuel: imported gas is replaced by domestically generated and increasingly renewable electricity, and the efficiency figures are the reason that substitution works at all. Government guidance puts heat pumps at more than three times the efficiency of a gas boiler¹², and Which? puts the typical range at three to four units of heat per unit of electricity¹¹.

The quote process is where that independence is either designed in or designed out. A system sized from a proper heat loss calculation, with emitters and controls specified to match, will run at a lower flow temperature and use less electricity for the same warmth. A system sized by rule of thumb may still heat the house, but it will lean harder on the grid and on the household's bills. The three-quote recommendation exists because that difference is invisible in a single quote.

The dependence that remains is real and worth stating. A heat pump needs electricity, and a household without on-site generation is buying that electricity from a supplier. Controls that rely on a manufacturer's app or cloud service add a second dependency, on a company rather than a network. Metering, whether required for a grant or chosen for monitoring, is what lets a household see whether the system is performing as designed, and it is worth having in the quote from the start¹⁸.