The Building Safety Levy may not come into force until 1 October 2026, but by now, developers should already be assessing what it means for their pipeline, viability appraisals and funding requirements.
While the levy has been introduced to fund the remediation of historic building safety defects, it will also no doubt impact future residential development projects across England.
For SME developers, the challenge – alongside the cost - is understanding how the levy interacts with planning, funding, cashflow and project programmes.
Crucial to know is that the levy will apply to most new residential developments where building control applications are accepted on or after 1 October 2026. The trigger is not the date planning permission is granted, but the building control process. There is no transitional arrangement, creating a hard deadline that developers need to be aware of.
The distinction is important. Schemes which secure building control acceptance before the deadline will fall outside the levy, even if the project progresses afterwards. As we navigate the busiest build period of the year, developers with consented sites should make it a priority to review programmes carefully and consider whether approvals can realistically be brought forward before October 2026. As the deadline approaches, bottlenecks within the approval process are a realistic possibility.
The financial impact will vary significantly by location and scheme type. The levy is charged on a pounds-per-square-metre basis, with rates varying by local authority and linked to local house prices. Gross internal area includes not only residential units but also communal corridors, stair cores, lobbies and amenity spaces. This is particularly relevant for build-to-rent and PBSA schemes, where extensive communal facilities can result in a much larger chargeable area.
This introduces a new layer of consideration for project design. Decisions that increase floor area can also increase levy liabilities. At a time when development appraisals are already under pressure from build cost inflation, planning obligations and regulatory requirements, another cost line is the last thing many housebuilders want, with potential to affect land values, loan-to-cost ratios and overall viability.
Cashflow may prove to be an even greater challenge. Unlike some development costs that are recovered through sales receipts, the levy must be paid before a completion certificate is issued or a building can be occupied. Failure to pay could delay occupations, sales completions and refinancing events. Developers and lenders alike will therefore need to ensure the liability is accounted for well before practical completion.
There are exemptions of course; small schemes of fewer than 10 dwellings, affordable housing, registered provider developments and certain supported housing projects are excluded, among others. However, exemption claims must be evidenced through the building control process, so as a lender, I’d urge developers to seek early advice early on and compile thorough documentation.
What’s more, whilst in theory some of those measures sound positive, there will still likely be knock-on consequences. With the levy now not applying to sub-10-unit schemes, experience has taught me that competition for smaller sites could intensify even more, as SME developers target sites that fall outside the charges. In some locations, this will also place further pressure on land values and make it harder to secure the most attractive small-site opportunities.
Alongside the levy, developers should also keep a close eye on permitted development rights. Office-to-residential conversions under Class MA remain an important delivery route for many SME developers, but prior approval is still required and local authorities can remove rights through Article 4 Directions.
Developers can often assume permitted development provides a straightforward shortcut through the planning system, but potential threats such as flood risk, contamination, transport impacts, natural light and neighbour amenity can all influence outcomes.
As with all regulatory changes, the common theme and recommended advice for housebuilders is to act sooner rather than later and ensure due diligence. Developers should be modelling levy liabilities now, reviewing project timelines, confirming exemption eligibility and stress-testing funding structures. They should also ensure planning assumptions remain valid, particularly where schemes rely on permitted development rights.
If the last couple of decades have taught us anything, it’s that the UK’s SME developers are nothing if not resilient - battling through constant rising costs, regulatory reform and economic uncertainty.
I’d urge those in the industry to see Building Safety Levy as just another adjustment – those who do prepare early, understand the detail and build the costs into their decision-making will be in pole position to keep projects moving and protect scheme viability in the years ahead.
