Brownfield Register Gaps: What Local Authorities Are Not Publishing

And what developers should do when the register does not tell the full story

Brownfield land registers were introduced in 2017 with a straightforward purpose: give developers a clear, up-to-date picture of where development-ready land exists across England. Every local planning authority was required to maintain one. Every register was supposed to be publicly accessible. The idea was sound.

The reality, seven years on, is considerably messier.

Across England, brownfield registers vary wildly in quality, completeness, and currency. Some local authorities publish detailed, regularly updated records. Others have registers that are years out of date, missing obvious sites, or so sparse they are functionally useless. For developers relying on these registers to find and screen sites, the gaps are not a minor inconvenience — they are a genuine risk.

This post examines where the gaps are, why they exist, and what you should actually do when the register does not tell the full story.

What the Brownfield Register Is Supposed to Do

Under the Town and Country Planning (Brownfield Land Register) Regulations 2017, local planning authorities in England are required to:

• Compile and maintain a register of brownfield land suitable for residential development
• Publish the register and keep it up to date
• Review it at least annually
• Include sites of 0.25 hectares or more, or capable of supporting five or more dwellings

The register is divided into two parts. Part 1 is the full list of brownfield sites considered suitable for housing. Part 2 is a subset of those sites that have been granted Permission in Principle — a faster route to planning consent.

In theory this gives developers a curated, regularly refreshed list of developable land. In practice, what they get is something considerably less reliable.

Where the Gaps Are

1. Outdated Records

The most common problem. Authorities are required to review their registers annually but "review" is loosely defined. Some authorities are publishing registers with sites that were last assessed in 2018 or 2019. Planning contexts change — sites get built out, fall through, or change ownership — and a register that was accurate three years ago may bear little resemblance to current reality.

A site showing as available on a register may already have full planning permission and be under construction. A site that became available two years ago may not appear at all.

2. Missing Sites

Brownfield registers are compiled by local authorities from a combination of their own knowledge, planning application history, and proactive site identification. They are not comprehensive surveys. Sites that have never had a planning application, sites in complex ownership, and sites that fall just below the size threshold are routinely absent.

Research by Historic England and various planning bodies has consistently found that brownfield registers capture only a portion of the actual brownfield land available in any given authority area. The actual supply of developable brownfield land in England is substantially larger than registers suggest.

3. Inconsistent Data Quality

Open the brownfield registers from ten different local authorities and you will find ten different approaches to what information is included, how sites are described, and what level of detail is provided. Some registers include detailed site assessments, constraints information, ownership details, and development potential. Others include little more than a site name, a grid reference, and an area figure.

This inconsistency makes comparison across authority boundaries extremely difficult. For developers working across multiple local authority areas, the register is useful in some places and almost worthless in others.

4. Part 2 Underuse

Permission in Principle — the mechanism that makes Part 2 of the register genuinely useful for developers — has been adopted by very few authorities in any meaningful way. Part 2 grants automatic permission in principle for housing development, removing a significant layer of planning uncertainty. But most authorities have granted Permission in Principle on very few sites, and some have granted it on none at all.

The result is that Part 2 — which should be the most powerful tool in the brownfield register — is largely empty across most of England. For developers, this removes the primary regulatory advantage the register was supposed to provide.

5. No Constraint Integration

Brownfield registers rarely include planning constraint data. A site may appear on the register as suitable for housing development, but the register will not tell you whether it sits within a flood zone, adjoins a conservation area, contains listed structures, or is affected by contamination that would require remediation before development.

This means the register cannot function as a standalone site screening tool. Any developer using the register to shortlist sites still needs to run independent constraint checks — flood risk, heritage, ecology, contamination — before the register entry becomes actionable.

Why the Gaps Exist

The brownfield register is an unfunded mandate. Local planning authorities are required to maintain registers but were not given additional resources to do so. In an environment of sustained local government funding pressures, registers compete for staff time with statutory planning functions — development management, plan-making, enforcement — that carry direct legal consequences when they fall behind.

Brownfield register maintenance, by contrast, carries almost no consequence when it lapses. Authorities are not penalised for publishing an out-of-date register, and the political incentive to maintain one is limited outside areas with acute housing delivery pressure. For many authorities, the register sits somewhere between a genuine strategic tool and an administrative afterthought.

There is also a methodological challenge. Identifying brownfield sites proactively requires resources — site visits, ownership research, planning history analysis, and engagement with landowners. Most authorities rely passively on sites surfacing through the planning application process rather than actively surveying their area for potential brownfield opportunities. This inherently limits the register to sites the authority already knows about, which is a subset of what actually exists.

The data standard itself contributes to inconsistency. While MHCLG published a brownfield land data standard, compliance is voluntary in practice, and the standard leaves considerable discretion in what information authorities include. The result is that even authorities making genuine efforts to maintain their registers produce outputs that vary significantly in depth and utility.

Finally, there is limited political pressure to improve register quality. Housing delivery targets are monitored through housing delivery tests and five-year land supply assessments, not brownfield register completeness. An authority can have a poor brownfield register and still meet its statutory duties.

There is also limited external pressure to maintain quality. Unlike planning applications which trigger statutory timescales and appeal rights, brownfield register quality is not actively monitored or enforced. The Planning Inspectorate does not scrutinise register quality as part of local plan examinations in any systematic way. The result is that registers which fall behind or become incomplete attract little formal consequence.

What Developers Should Do

Understanding the limitations of brownfield registers is the first step. Knowing how to work around them is what matters practically.

Treat the register as a starting point, not a definitive source. A site appearing on the register confirms it has been assessed as potentially suitable for development at some point. It does not confirm current availability, ownership, planning status, or the absence of constraints. Use it to generate leads, not to make decisions.

Cross-reference against planning application history. A site on the brownfield register that also has recent planning application activity — particularly applications for residential development — tells a more complete story than the register entry alone. Planning application data for England is publicly available and searchable.

Check constraint layers independently. Brownfield registers rarely include detailed constraint information. A site may appear clean on the register but sit within a flood zone, adjoin a conservation area, or be affected by a Tree Preservation Order. These constraints should be verified independently for any site under serious consideration.

Look beyond the register for off-register brownfield land. The most sophisticated developers treat the brownfield register as one data source among several rather than the primary filter. Former industrial land, redundant retail sites, underused car parks, and surplus employment land frequently appear in planning application histories and aerial imagery long before they make it onto a brownfield register — if they ever do.

Engage the local planning authority directly on promising sites. For sites that look viable but have limited register information, a pre-application enquiry or informal discussion with the LPA can establish current status, any known constraints, and whether the authority would support a residential application. This intelligence is not available from any register.

What Good Data Practice Looks Like

The inconsistency in brownfield register quality is not inevitable. Local authorities that maintain high-quality registers tend to share certain characteristics: dedicated planning policy resource, a proactive approach to site identification, and integration of register maintenance into wider planning policy workflows rather than treating it as a standalone task.

The gap between the best and worst registers is significant. A developer working in an authority with a well-maintained, detailed register is starting from a fundamentally different information position than one working in an authority where the register is three years out of date and contains twenty entries.

Understanding which authorities maintain good registers — and which do not — is itself useful information for prioritising where to focus site-finding activity.

The Bottom Line

Brownfield registers are a useful tool that falls well short of what they were designed to be. The gaps are real, widespread, and consequential for developers who rely on them without understanding their limitations.

The developers who use brownfield registers most effectively treat them as one layer of intelligence among many — a useful starting point that needs to be tested, cross-referenced, and supplemented with independent constraint checking, planning application history, and direct LPA engagement before any meaningful site assessment can be made.

For every site that looks clean on a brownfield register, the question is not whether it is available but whether the constraints data supports that assessment. That verification step is where the real work — and the real competitive advantage — lies.