What counts as evidenced unmet need in the 2026 NPPF?

The open version, outside the Green Belt

S5(1)(j) allows development which would address an evidenced unmet need, and gives a five year supply failure and a delivery test result below the threshold as examples rather than as limits. The phrase used is 'including, but not limited to'.

So an unmet need for affordable housing, for homes for older people, for rural housing, or for self-build plots can all qualify, provided the need is genuinely evidenced.

The closed version, inside the Green Belt

The grey belt route also requires an evidenced unmet need, but a footnote defines it. For applications involving housing it means the lack of a five year supply of deliverable sites, including the relevant buffer where applicable, or a delivery test result below the threshold over the previous three years.

The word is 'means', not 'includes'. That closes the category. A council failing its self-build duty, or an evidenced shortage of homes for older people, does not reach this limb however well documented.

Why this matters most for self-build

A council that has not granted enough planning permissions to meet demand on its self-build register is in breach of a statutory duty. Outside the Green Belt that is an evidenced unmet need and it opens a route.

Move the identical site into the Green Belt and the same fact stops helping. If you are looking at Green Belt land for self-build, the better door is usually the land-around-a-station route, which carries no unmet need test at all.

Where to find the figures

Delivery test results are published annually by the government, one figure per authority. Five year supply is not centrally published: it comes from each council's own position statement or annual monitoring report, and it is actively contested, so an appeal decision often carries more weight than the council's own claim.