Building Safety Levy calculator: the levy on your scheme

1. [1] The rates. Schedule 3 of the Building Safety Levy (England) Regulations 2025 sets a rate per square metre for each of 298 local authority areas, a previously developed land rate and a standard rate, from £6.35 and £12.70 in County Durham to £50.17 and £100.35 in Kensington and Chelsea. The calculator carries every row. The Building Safety Levy (England) Regulations 2025, Schedule 3: rates by local authority
2. [2] The calculation. The levy is the area rate times the chargeable floorspace. The government's own worked example: 20 houses of 100m² on previously developed land in Dover at £15.19 per m², £30,380. GOV.UK: Building Safety Levy technical consultation, government response
3. [3] Who pays and when. The levy applies from 1 October 2026 to building control applications and initial notices for new residential development in England, unless exempt. Developments of fewer than 10 new dwellings, or fewer than 30 PBSA bedspaces, are exempt. Guildford Borough Council: Building Safety Levy information for developers
4. [4] The brownfield rate. The discounted rate is 50% of the standard rate and applies where at least 75% of the land within the planning red-line boundary is previously developed land. Telford & Wrekin Council: Building Safety Levy
5. [5] Not tested. The calculator does not test the other exemptions (affordable housing, certain care and specialist housing, and others the Regulations list), how floorspace is measured on a mixed-use scheme, or any refund. The collecting authority's levy notice is the figure you pay.

This calculator applies the rates in Schedule 3 of the Building Safety Levy (England) Regulations 2025 to the figures you enter; it is not legal, tax or planning advice and the collecting authority's levy notice is the figure you pay. An enquiry sent through the form is read and answered by Joe, who runs this site; no firm receives it.