BUS Grant Application Step-by-Step UK 2026

Every BUS application starts with an MCS-certified installer visiting your property + producing a heat loss survey. The survey determines:

• Heat pump capacity needed (5kW for small properties, 7-10kW for typical 3-bed, 12-16kW for 5-bed detached).
• Distribution requirements (radiator upgrades, underfloor heating, hot water cylinder size).
• Electrical supply assessment (DNO consent + any required upgrade).
• Heat pump location + outdoor unit siting.

Typical timeline: 1-2 weeks from initial enquiry to survey appointment, plus 3-7 days for the installer to produce the survey report. Most installers offer free surveys; a few charge GBP 50-150 (refunded if you proceed with their quote).

Based on the survey, your installer issues a detailed quote that breaks out:

• Heat pump unit cost (model, capacity, refrigerant type)
• Indoor unit + hot water cylinder cost
• Pipework + radiator changes + electrical work
• DNO consent + supply upgrade (if needed)
• BUS grant deduction shown explicitly as negative line item (-£7,500)
• Commissioning + first-year service inclusion
• Warranty terms (years + scope)

The installer also checks your property's BUS eligibility against Ofgem's criteria:

• Property is a domestic UK residence (not a commercial building or holiday let).
• Property has not received BUS in the last 7 years.
• Existing heating system is fossil-fuel (gas, oil, LPG) - new-build properties without prior heating typically not eligible.
• EPC requirement: most installers ask for a valid EPC (within 10 years); some BUS funding programmes require minimum EPC rating.

Once you accept the quote, the installer submits the BUS application to Ofgem's BUS portal on your behalf. The application includes:

• Property address + UPRN (Unique Property Reference Number)
• EPC reference (if available)
• Heat pump model + capacity + MCS certification number
• Installer's MCS certification details
• Customer consent declaration

This is the step where you, as the customer, sign the consent declaration confirming:

• You authorise the installer to claim the grant on your behalf.
• The grant is paid directly to the installer (you never receive the money).
• You understand the 7-year exclusion period for re-applying.
• The property meets BUS eligibility criteria.

Ofgem reviews the BUS application + confirms eligibility:

• Standard approval timeline: 2-7 business days for clean applications.
• Documentation request: if Ofgem needs additional information (e.g. UPRN clarification, EPC discrepancy), they query the installer; expect another 3-5 business days.
• Rejection: rare but possible. Common rejection reasons covered in the next section.

Approval confirms two things: (a) your property is eligible for £7,500 toward this install, and (b) the installer's reimbursement is secured. Most installers will not start the install before BUS approval is confirmed (avoids the risk of installing without the grant + needing to chase the customer for the full pre-grant amount).

Once BUS is approved, the install proceeds per the agreed schedule. On the customer invoice:

• Gross install cost (e.g. GBP 11,000)
• BUS grant deduction (-£7,500)
• Net amount due from customer (GBP 3,500)

You pay the installer the net amount only. Reputable installers offer 0% finance over 24-60 months on the net amount, so the actual cash outlay can be GBP 60-150/month rather than the full GBP 3,500 upfront.

After commissioning, the installer submits commissioning evidence to Ofgem:

• Commissioning certificate (signed by MCS-certified engineer)
• System efficiency test results
• Customer handover sign-off
• Final BUS grant payment claim

Ofgem pays the £7,500 to the installer typically within 30 days of receiving the commissioning evidence. From the customer's perspective this is invisible - you've already paid the net amount + don't see the reimbursement transaction.

Your property is now registered as having received a BUS grant. Implications:

• 7-year exclusion: the property cannot receive another BUS grant for 7 years from the install date. If you replace the heat pump within that period (e.g. due to fault, choice, or property sale), the new install would not qualify for BUS.
• Property sale: the BUS-funded heat pump stays with the property - it's part of the building, not removable. Future buyers benefit from the install without losing BUS eligibility (because they didn't claim it themselves).
• Warranty + maintenance obligations: the heat pump's manufacturer warranty + annual service requirements continue independently of the BUS grant.

1. Property already received BUS in the last 7 years. Check the property's history before applying - previous owners may have claimed BUS for an earlier install. Your installer can verify with the local council's records office.
2. Non-residential property classification. Holiday lets + commercial properties are typically excluded. Mixed-use properties (shop with flat above) may need additional documentation showing the residential portion. Confirm with your installer + Ofgem before signing.
3. Missing or expired EPC. Some installers proceed without one + sign a customer declaration; some require one. Get a current EPC (within 10 years) for your property before applying - costs GBP 60-120.
4. Insufficient heat-loss survey documentation. Cheap installers cutting corners on the MCS survey produce documentation Ofgem won't accept. Use only MCS-certified installers with strong track records - your iter-2 installer-vetting checklist applies.
5. Heat pump model not on MCS-approved list. Only MCS-certified heat pump models qualify. All major UK brands (Vaillant, Daikin, Mitsubishi, Octopus Cosy, Viessmann, Nibe, Grant) are on the list; confirm before signing the install contract.