Since the introduction of the 'grey belt' designation under the revised National Planning Policy Framework (NPPF) in December 2024, early signs show it is having a transformative impact on housing development opportunities across the country.

Recent analysis highlights that more than one in three housing applications on grey belt land have been approved, demonstrating the significant shift this policy brings to the planning landscape. In particular, consultancy Marrons reports that 36% of housing applications on grey belt sites received approval between December and March – a notable uplift compared to previous periods. Planning appeals tell a similar story, with success rates for green belt challenges rising from 31% to 49% year-on-year.

Prior to the introduction of the grey belt, reviews of green belt land typically found that only around 15% of sites made a low or no contribution to green belt purposes. Post-reform, this figure has surged to 60%, suggesting that councils and decision-makers are adopting a more pragmatic and evidence-led approach to green belt assessments.

While the grey belt policy is still bedding in, its early implementation is already providing greater clarity and opportunity for both developers and local authorities. The planning system appears to be moving toward a more objective assessment of sites, although some variation in decision-making remains, given the inherently case-by-case nature of planning judgments.

What is particularly encouraging is the growing confidence among planning officers and elected members in recognising and supporting grey belt sites through the application and appeal processes. Several major housing schemes have now secured consent at the local level, setting positive precedents for others to follow.

Ultimately, agreeing that a site qualifies as grey belt can materially de-risk the planning process, providing a faster and more certain route to consent. For landowners, developers, and investors, understanding how to navigate the new grey belt framework is now essential to unlocking development opportunities in 2025 and beyond.

At Hex Land Partners, we continue to monitor how this policy evolves and advise our clients on the best strategies to maximise the opportunities it presents.