Heritage Statement vs Heritage Impact Assessment , Which Do You Need?
A Heritage Statement (also called a Statement of Heritage Significance) follows HEAN 12. It is the proportionate document for Grade II minor and conservation-area works, typically two to six pages, £150 to £400. A Heritage Impact Assessment follows GPA 2. It is the fuller document for Grade I, Grade II*, demolition and strategic cases, typically ten to forty pages, £800 to £3,500.
Legal anchor for each
Neither term appears verbatim in primary legislation. Both serve the applicant's NPPF ¶200 duty to provide a description of significance proportionate to the asset's importance. HEAN 12 sets out what 'proportionate' looks like at the short end of the spectrum; GPA 2 sets out the longer document.
Typical length and fee
| Document | Typical length | Typical fee (2026) |
|---|---|---|
| One-page Heritage Statement | 1 page | £150 to £400 |
| Statement of Heritage Significance | 2 to 6 pages | £400 to £800 |
| Heritage Impact Assessment (Grade II) | 10 to 25 pages | £800 to £3,500 |
| HIA (Grade I or strategic) | 25 to 40 pages | £3,500 to £12,000 |
Which one your LPA actually wants
The single most reliable signal is the wording of the LPA's pre-application response. If the pre-app letter says 'Heritage Statement', do not over-deliver an HIA (you are wasting fee). If it says 'Heritage Impact Assessment', do not under-deliver a Statement (the application will be returned).
In the absence of pre-app advice, default rules: Grade II minor or conservation-area minor → Statement; everything else → HIA. London LPAs (Westminster, Kensington, Camden) tend to ask for HIA earlier than rural authorities; WHS authorities (Bath, Canterbury, Edinburgh) ask for HIA at conservation-area-only sites where a Statement would do elsewhere.
Can a Statement be upgraded to an HIA?
Yes , the structural backbone (significance, proposal, impact, mitigation) is the same. An HIA is best thought of as a longer, more granular Statement with additional evidence (photographic survey, comparative analysis, historical research). Asking your consultant for a Statement first and then commissioning an HIA on top if needed is more expensive than asking for the HIA upfront.