Building Safety Levy (Amendment) (England) Regulations 2026: Clarifying the Brownfield Discount

Following the implementation of the Building Safety Levy (BSL), which came into force on 1 October 2026, the Government has introduced a number of targeted amendments through the Building Safety Levy (Amendment) (England) Regulations 2026.

While most of the changes are relatively narrow, one amendment is of particular significance to developers and their advisers: the revision of the definition of Previously Developed Land (PDL) for the purposes of the 50% ‘Brownfield Discount’. The amendment is important because it seeks to resolve a mismatch between the original levy regime and the concept of PDL familiar to planning law practitioners.

The Building Safety Levy and the PDL Discount

The BSL applies to strategic residential developments requiring a building control application in England, including build-to-rent schemes and purpose-built student accommodation (PBSA). It is intended to raise funding to remediate historic unsafe residential buildings. A number of developments are exempt, including affordable housing, care homes, supported housing and schemes comprising fewer than 10 dwellings (or fewer than 30 PBSA bedspaces).

A key feature of the regime is a 50% reduction in the levy rate where the development takes place on land that qualifies as PDL and at least 75% of the site falls within that definition.

Given that levy rates can be substantial, the availability of the discount may have a material impact on development viability.

The problem with the original definition

Under the 2025 Regulations, land generally qualified as PDL where a qualifying building had previously existed on the site.

However, the drafting created uncertainty over whether certain common features of brownfield land, such as surface-level infrastructure and hardstanding, constituted a ‘building’ for these purposes. This was problematic because it diverged from the well-established planning concept of previously developed land contained in the National Planning Policy Framework (NPPF). It also led to disputes between developers and authorities.

Planning practitioners have long understood brownfield land to encompass a wider range of developed sites, including areas occupied by permanent surface infrastructure. By contrast, the original BSL definition risked excluding sites that would plainly be regarded as brownfield in planning terms.

The result was the prospect of an awkward disconnect between the planning and building control regimes. A developer may have secured planning permission on the basis that a site was recognised as brownfield land, only to discover that it did not qualify for the levy discount because the relevant historic development did not meet the narrower levy definition.

The 2026 Amendments

The 2026 Amendment (England) Regulations broaden the definition of a qualifying building. The revised definition now encompasses not only permanent buildings but also other permanent man-made structures or erections.

Importantly, it expressly includes:

• areas reinforced for load-bearing purposes;
• paved or surfaced areas;
• fixed plant and machinery; and
• similar permanent structures.

The practical significance of the amendment is that features such as car parks, service yards and other hardstanding can now constitute previously developed land.

This change is likely to bring the BSL regime much closer to developers’ and planners’ existing understanding of brownfield sites and should reduce the scope for disputes about whether a site qualifies for the discount.

Alignment with the planning definition

Perhaps the most noteworthy aspect of the amendment is its policy objective of aligning the levy regime with the planning framework. The Government expressly acknowledged that the original levy definition was inconsistent with the planning understanding of PDL and that the amendment is intended to facilitate greater consistency between planning and building control assessments.

For developers, this alignment should improve certainty. When undertaking site acquisition, viability assessments and development appraisals, advisers can now approach the levy discount with greater confidence that land recognised as brownfield during the planning process will also be treated as previously developed when levy liability is assessed.

That said, the definitions are not identical, and practitioners should continue to analyse the specific wording of the levy regulations rather than assuming that a planning authority’s characterisation of a site will automatically determine levy treatment.

Important limitations

The amendments do not open the door to every historic operation being counted as previously developed land. Two important exclusions remain. First, wholly underground buildings and structures are excluded. In addition, underground elements that extend beyond the footprint of any above-ground structure are disregarded when assessing whether land qualifies as PDL.

Secondly, the amendments clarify that unlawful development does not count. Where operations carried out on, over or under the land were unlawful for planning purposes, the relevant land cannot be treated as previously developed for the purposes of the discount.

This clarification may create a new area of dispute. Historic planning records are often incomplete, particularly on older industrial or commercial sites. Questions may therefore arise as to whether historic structures were authorised, benefited from permitted development rights, or became lawful through the passage of time.

Practical implications

For most brownfield developers, the amendments are welcome. The broader definition should increase the number of sites capable of qualifying for the 50% discount and provide a clearer basis for assessing levy exposure at an early stage. Developers of former commercial premises, industrial estates and sites dominated by hardstanding are likely to benefit most.

More broadly, the amendments demonstrate an attempt by Government to ensure that the levy operates consistently with established planning concepts. While developers will still need to undertake careful due diligence, particularly where there are questions around historic legality, the revised definition should reduce uncertainty and help align planning and building control outcomes in relation to brownfield development.