COSDON CONSULTINGBNG exemptions changed on 6 August 2026 — here's what's different
If you're working on a planning application in England, it's worth pausing before you assume your old assumptions still hold. Here's a plain-English run through what actually changed, and where the catches are.
Sites under 0.2 hectares are now exempt
If your site is 0.2 hectares or less within the red line boundary, it's now exempt from mandatory BNG. There's one significant condition: if the development would impact priority habitat, the exemption falls away and the standard requirements still apply.
The trap here is assuming you're in the clear simply because the site is small. Priority habitat being present isn't automatically the problem; what matters is whether your proposals would actually affect it. The only way to know that is a baseline habitat survey, and it's far cheaper to establish early than to discover after you've submitted.
The self-build and custom-build exemption is gone
The dedicated exemption for self-build and custom-build housing no longer applies to applications submitted from 6 August onwards. In practice most of these schemes will fall under the new 0.2 hectare exemption anyway; but the point is you can no longer rely on the self-build route on its own. It has to be the site size doing the work now, not the housing type.
A new exemption for temporary development
If the land is going to be reinstated within five years, it's now exempt. The same condition applies as with small sites: it turns on whether priority habitat would be impacted, not merely whether it's present.
More flexibility for minor development
Previously, you had to demonstrate you'd maximised on-site options before you were allowed to deliver gains off-site. That requirement now only applies to major development.
For minor development still subject to BNG, you can weigh on-site and off-site gains together from the outset, rather than justifying off-site as a fallback. Statutory biodiversity credits remain the last resort either way; that part hasn't changed.
What this doesn't change
This is the part worth reading twice. Being exempt from BNG does not mean you're exempt from everything else. Protected species licensing, statutory site designations, and local plan policy all still apply regardless of your BNG position. A 0.2 hectare site with no BNG requirement can still need a great crested newt or dormouse licence if the survey turns something up.
Two more that catch people out: varying an existing permission under section 73 doesn't automatically hand you the new exemptions; the BNG position usually follows whatever was in place on the original permission, so check the transitional arrangements carefully before you submit. And Nationally Significant Infrastructure Projects (NSIPs) get mandatory BNG from November 2026; a separate change, but worth flagging if you're working at that scale.
The honest takeaway
Assuming an exemption applies without checking is the easiest way to either over-deliver when you didn't need to, or find yourself challenged later. Both are avoidable. The whole point of getting a position checked properly is that you act on what the site actually requires; not on an assumption that turns out to be wrong at the worst possible moment.
Not sure where your site stands?
If you want a clear, honest read on whether an exemption applies to your development, get in touch; it's a lot cheaper to know than to guess.
Get in touchThis article reflects our understanding of the position as of August 2026 and is general guidance, not site-specific advice. BNG rules, thresholds and exemptions can change and depend on your particular scheme and local planning authority; always confirm the current position for your project before relying on it.