Boiler Upgrade Scheme (BUS) Statistics 2026

The Boiler Upgrade Scheme (BUS) is the UK government's flagship grant scheme for low-carbon heating in England and Wales, launched in May 2022 and extended through 2028. Administered by Ofgem, it provides upfront grants for air source heat pumps, ground source heat pumps and (in eligible rural areas) biomass boilers. This page summarises BUS application numbers, voucher claim rates, regional uptake and technology split based on Ofgem's BUS dashboard reporting.

BUS application and voucher numbers

According to Ofgem's BUS dashboard, application volume has grown sharply since the grant uplift to £7,500 in late 2023. Approximate cumulative voucher issue and redemption figures are as follows:

Cumulative vouchers redeemed are estimated to pass ~60,000 by the end of FY25/26, although turnover varies as the scheme's annual allocation is reset each financial year.

Voucher claim rate

The conversion gap between vouchers issued and vouchers redeemed has been a persistent feature of BUS. Industry analysis of Ofgem BUS data points to:

• Average voucher redemption rate: approximately 70-80%
• Common reasons for non-redemption: project drop-out, surveys revealing unsuitability, householder change of mind, expired voucher window (initially 3 months, extended to 6 months in 2023)
• Time from voucher issue to redemption: typically 2-4 months for ASHP installations
• Voucher value claimed (post-uplift): primarily £7,500 for ASHPs and GSHPs

Regional distribution

BUS covers England and Wales (Scotland operates its own Home Energy Scotland Grant scheme). Regional distribution of BUS-redeemed vouchers shows clear concentrations in rural and off-gas regions:

Source: Ofgem BUS regional reporting; figures are approximate annual averages.

Technology split

Air source heat pumps dominate BUS vouchers redeemed, reflecting the wider UK heat pump market. Approximate technology split is:

The ASHP share has held broadly steady since BUS launch. Biomass uptake remains low partly because the eligibility test (off-gas-grid rural property) and grant value (£5,000) are more restrictive than for heat pumps.

BUS scheme funding outlook

The BUS budget was uplifted in 2024 and the scheme extended to March 2028. Approximate annual budget allocations:

• FY22/23: approximately £150 million initial allocation
• FY23/24: approximately £150 million
• FY24/25: approximately £150 million with topped-up rolling commitments
• FY25/26: announced increases bringing total scheme spend over 2025-2028 to over £1.5 billion

Demand growth has tested annual allocation in some quarters; budget headroom is monitored monthly via Ofgem BUS dashboard.

BUS application volume seasonality

BUS application volume shows clear seasonal patterns reflecting heating-system replacement timing. Approximate share of annual BUS applications by quarter:

• Q1 (Jan-Mar): typically ~22-26% of annual applications, often after winter heating-system failures
• Q2 (Apr-Jun): typically ~24-28%, peak survey season ahead of summer install
• Q3 (Jul-Sep): typically ~26-30%, summer install season delivers the highest commissioning volume
• Q4 (Oct-Dec): typically ~20-24%, slower as winter approaches

Peak voucher redemption (commissioning) typically occurs in Q3, lagging application by 8-16 weeks. Capacity constraints in installer scheduling typically tighten in late Q2 through Q3 and ease materially in Q4.

BUS commentary and householder satisfaction

Industry surveys and householder feedback suggest BUS-funded heat pump installations have generally high satisfaction levels but with consistent themes around process complexity. Approximate findings from recent industry surveys:

• Overall satisfaction with installed heat pump (very/fairly satisfied): typically ~80-87%
• Satisfaction with running costs vs prior system: typically ~65-72% report cost-positive or cost-neutral outcomes (varies sharply by prior fuel)
• Satisfaction with comfort vs prior system: typically ~75-82% report equal or better comfort
• Common dissatisfaction themes: longer warm-up times, noise of outdoor unit, complexity of controls, perceived high running cost when paired with poor flow temperature setup
• Recommend a heat pump to a friend (NPS-style): typically positive net score in the +30 to +55 range

Satisfaction is materially higher when installations include flow-temperature design, weather compensation and proper cylinder/distribution sizing, reinforcing the importance of installer skill rather than equipment alone.

BUS in the wider context of UK heating decarbonisation

BUS-funded heat pumps remain a small but rising fraction of the wider UK heating market. Approximate context for 2024-2025:

• UK households with mains gas as primary heating: approximately ~22 million
• UK households with non-gas primary heating: approximately ~6-7 million
• Cumulative MCS-certified heat pump installs (BUS plus non-BUS) by end-2025: approximately ~250,000
• Heat pump share of UK total heated dwellings: approximately ~1% by end-2025
• Government policy ambition: a step-change to ~600,000 annual heat pump installs by 2028

The gap between current BUS-funded volumes (~30,000-35,000 vouchers per year) and the long-term ambition implies a roughly 15-20x scale-up over the second half of the 2020s, requiring large-scale installer and supply-chain expansion.

BUS interaction with other UK low-carbon heat policies

BUS sits within a wider UK policy framework for low-carbon domestic heating. Key adjacencies:

• Future Homes Standard: incoming building regulations expected to ban gas boilers in new homes from 2025 onward, materially shifting new-build heating to heat pumps and direct electric.
• Clean Heat Market Mechanism (CHMM): proposed obligation on boiler manufacturers to deliver a rising share of low-carbon heat appliances annually.
• Heat Network Zoning: emerging policy designating geographic zones where new buildings or major refurbishments must connect to heat networks.
• Home Energy Scotland Grant: Scotland's parallel grant providing up to £7,500 plus an interest-free loan for heat pump installations.
• Welsh Government Warm Homes Programme: targeted Welsh-specific programme that complements BUS in qualifying properties.

BUS, taken alongside these adjacent levers, forms the policy stack underpinning the UK heat pump ramp through the late 2020s.

BUS administrative cost and overhead

The BUS scheme is administered by Ofgem with annual administrative costs reported in DESNZ accounts. Approximate scheme administrative metrics:

• Annual BUS admin cost (Ofgem operations): approximately £5-8 million
• Admin cost as a share of total scheme spend: approximately ~3-5%
• Average installer-side admin time per voucher application: approximately 1-2 hours
• Householder direct paperwork time: typically under 1 hour (signing forms; installer manages the application)

BUS is designed as a low-friction grant from the householder perspective, with the installer carrying most of the application load.

BUS-funded heat pump install volumes by quarter

Quarterly BUS voucher redemption data shows clear seasonality and step-change uptake post the late-2023 grant uplift. Approximate quarterly redemptions:

Source: Ofgem BUS dashboard quarterly snapshots, with light approximation for chart-friendly rounding.

BUS application process and average timelines

BUS vouchers are applied for by the MCS-certified installer on behalf of the householder, against a confirmed quote. Typical process timelines reported by industry sources are as follows:

• Initial enquiry to MCS-certified survey: typically 1-3 weeks
• MCS survey to formal quote: typically 1-2 weeks
• BUS voucher application submission: same day to 1 week
• Ofgem voucher issue: typically 5-15 working days
• Voucher issue to install completion: typically 4-12 weeks depending on installer schedule and equipment availability
• Total enquiry-to-commissioned timeline: typically 10-22 weeks

The original 3-month voucher window proved too short for many installs, which is why Ofgem extended the window to 6 months in 2023.

BUS-funded installation property profile

The typical BUS-funded property profile leans toward owner-occupied detached and semi-detached houses with off-gas heating systems. Approximate property profile of BUS-redeemed installs:

Source: industry analysis of MCS-cert install records cross-referenced with EPC register data.

Data caveats

The following caveats apply to BUS statistics:

• BUS only covers England and Wales; Scotland's grant data is reported separately under Home Energy Scotland.
• Ofgem BUS dashboard updates rolling figures monthly; quarterly snapshots can shift retroactively as redemptions are confirmed.
• FY25/26 figures are partial and estimated; the financial year does not close until March 2026.
• Regional shares are approximate annual averages; quarterly variation is wider.
• The scheme grant value uplift in late 2023 affects pre/post comparisons.
• Property profile data is inferred from installer-side records and may slightly under-represent flat conversions.

The Boiler Upgrade Scheme has matured rapidly since the 2023 grant uplift, with annual voucher volumes now over 25,000 and redemption rates settling around 70-80%. ASHPs dominate the technology split and rural English regions account for the largest regional shares. The typical BUS-funded property is a detached or semi-detached home off the mains gas grid, which is consistent with the scheme's role as a transition route for oil and LPG households. Use this data freely with attribution to ecosavinghub.co.uk. Last updated: 2026-05-08.