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UK Grant Calculator

Boiler Upgrade Scheme Calculator

Use this educational estimator to understand potential Boiler Upgrade Scheme (BUS) support. It is not an official approval tool and does not replace installer-led eligibility checks.

Last reviewed: 2026-04-28Confidence: medium
Confidence: medium

Page review status

Written by: HeatWise Home Editorial Team

Reviewed by: Editorial review by HeatWise Home

Review status: Internally reviewed for clarity, source consistency, and calculation assumptions.

Expert review: Not currently externally expert-reviewed.

Last updated: 2026-04-28

Last reviewed: 2026-04-28

Confidence: medium

External expert review: HeatWise Home does not currently publish named external expert reviewers. We are working toward adding independent review from qualified retrofit, heating, or building-energy professionals. Until then, users should treat our calculators and guides as educational planning tools and confirm decisions with official sources and qualified installers.

Medium confidence

Energy prices, grant rules, and installation costs change frequently. The figures on this page are planning ranges, not quotes. Always confirm your current tariff, delivered fuel price, installer scope, and eligibility in the named references linked below.

Helpful next step

See formulas, assumptions, and limits behind each estimate.

Read our calculator methodology

Current BUS grant values (planning view, checked 2026-04-28)

Grant values should be verified directly against GOV.UK and Ofgem before quote acceptance.

The estimator below is for planning scenarios only.

TechnologyGrant valuePlanning note
Air-to-water heat pump£7,500Installer-led BUS application
Ground source heat pump£7,500Includes eligible water source systems
Air-to-air heat pump£2,500Listed in current GOV.UK BUS guidance
Biomass boiler£5,000Additional eligibility restrictions apply

Inputs this estimator asks you to confirm

1) Property location (England or Wales) and ownership type.

2) Existing heating system being replaced (fossil fuel or electric baseline).

3) Proposed technology (air-to-water, ground source, air-to-air, biomass where eligible).

4) Installer status (MCS-certified and able to submit BUS applications).

5) Whether homeowner consent and timing requirements can be completed on schedule.

Installer-led process and homeowner consent

BUS is installer-led. The installer applies through Ofgem and the property owner confirms consent before voucher issue.

This page does not replicate official approval logic. It is designed to help homeowners ask better quote and eligibility questions.

Quote deduction and cash-flow planning

In standard BUS flow, the grant is deducted from your quote/invoice upfront, and the installer redeems the voucher afterward.

Use the net-of-grant quote in your payback and affordability checks, then compare with scenarios where eligibility fails or timing is missed.

Recommended next steps

Confirm current GOV.UK and Ofgem eligibility wording for your property and technology.

Ask installers to show MCS credentials and BUS application experience in writing.

Use the UK heat pump cost calculator and calculator methodology page to test low/medium/high scenarios before signing.

Disclaimer

This Boiler Upgrade Scheme Calculator is an independent educational estimator and is not operated by GOV.UK, Ofgem, or MCS.

It does not grant approval, reserve vouchers, or guarantee eligibility. Homeowners must verify all rules and timelines with official sources and qualified installers.

Key planning routes

Related pages

Sources and assumptions

Last checked: 2026-04-28. Confidence: medium.

  • Electricity price range: GBP 0.22-0.34 per kWh (Ofgem regional cap spread and available tariffs).
  • Gas price range: GBP 0.05-0.11 per kWh (Ofgem cap benchmark and regional/tariff variation).
  • Heating oil equivalent range: GBP 0.09-0.13 per kWh equivalent (kerosene supplier tracking, delivery-size and season dependent).

Caveat: prices vary by supplier, tariff, region, standing charge, and usage. Use your live bill and tariff for final decisions.

Read calculator methodology

Frequently asked questions

No. BUS applications are installer-led and final checks are completed through official processes.

Request local quotes or guidance

Send a homeowner question, correction, partnership note, or request for help comparing energy upgrades.

Privacy and referral transparency

  • There is no obligation to proceed after you submit this form.
  • We do not routinely share your details with third parties.
  • Partner introductions only happen where relevant to your request.
  • Your data is handled according to our Privacy Policy.

What happens next:

  1. We review your question or quote request.
  2. We may reply directly or ask for missing details.
  3. If a partner introduction is relevant, we explain who the partner is before sharing your details.
  4. You are under no obligation.
  5. Your data is handled according to our Privacy Policy.

If we suggest a partner

Where we suggest a partner, we aim to prioritise relevant, reputable providers or installers. We do not recommend proceeding without checking credentials, quotes, warranties, and official grant requirements.

Helpful next step

Pressure-test savings assumptions before committing to upgrades.

Compare heat pump vs gas