Your development

Local authority

Does any of these apply? The application was submitted before 1 October 2026 The building is an excluded use (e.g. hospital, care home, hotel or hostel, children's home, school accommodation) The client is a non-profit registered provider of social housing (or its wholly owned subsidiary)

The planning permission (whole development) New dwellings for an existing building, dwellings after the work minus beforeNew PBSA bedspaces purpose-built student accommodation; net, as above

New floorspace in this application, gross internal area (m²) Chargeable dwellings market sale, private rent and other non-exempt homes Student accommodation (PBSA) Exempt dwellings social or supported housing Communal areas used only by chargeable homes stairs, lobbies, plant, residents' gym Communal areas shared with exempt homes or other uses charged pro rataOther floorspace using those shared areas e.g. shops or offices sharing a lobby; exempt homes are counted automatically

Existing floorspace (conversions and extensions of residential buildings) Existing dwellings or PBSAExisting communal areas

Previously developed land? No Yes (at least 75% of the land within the planning permission's red line, or permitted development) Not sure

How the estimate works

When it's charged. All three charging conditions must be met. The planning permission must be for major residential development (10 or more new dwellings, or 30 or more PBSA bedspaces), judged on the whole development rather than this application. The work must create new residential floorspace. The client must not be an exempt person.
Chargeable floorspace. The gross internal area of new chargeable dwellings and PBSA, plus communal areas that serve them, less any existing residential floorspace. A communal area shared with exempt homes or other uses is charged in proportion to the chargeable homes' floorspace among everything using it.
Rate. Chargeable floorspace × the rate per m² for the local authority the building is in. On previously developed land the rate is half.

Limits: run each building separately. The charge is worked out per building, and a building whose result is negative counts as nil, so pooling buildings could hide or overstate a charge. A building in two local authorities takes the rate of the one containing the greater part of it. Communal areas in a building with no homes or PBSA (e.g. a separate bin store) aren't chargeable. Previously developed land also has conditions this tool doesn't check (the earlier use must have been lawful, and agricultural, forestry, mineral and landfill sites don't count). It assumes shared communal areas serve the homes entered above (the guidance counts every unit across the whole development that uses them). It can't judge exemptions such as shared ownership or First Homes, which have conditions. The collecting authority calculates the actual charge, so treat this as an estimate. For what a higher-risk building application must include, see building safety levy information in a Gateway 2 application.

Sources

MHCLG, "Building Safety Levy: Guidance", section 1 (chapter 3, levy charging conditions and exclusions) and section 2 (chapter 4, calculation; chapter 5, rates by local authority), GOV.UK, updated 2 July 2026. Rates as published there on 14 October 2026.
The Building Safety Levy (England) Regulations 2025, SI 2025/1236.

An estimate based on the published guidance, not a levy determination or tax advice. Contains public sector information licensed under the Open Government Licence v3.0.