The self-build that moved on – and the CIL that didn’t: inside the High Court’s ruling

First, once a chargeable development is commenced, CIL liability arises irrespective of whether the scheme is ultimately completed. Liability Notices and Demand Notices record that liability; they do not create it. That approach aligns with the statutory scheme and prior authority. Practical point: avoid commencing works until any exemptions or transfers are secured in writing and acknowledged by the authority.

Second, a self-build exemption can be withdrawn before completion where a disqualifying event occurs “before the end of the clawback period”, including when it occurs before the start of the clawback period. The Court held that selling the site to a developer was a change such that the project ceased to be “self-build housing,” triggering withdrawal under Regulation 54D(2)(a). The exemption regime requires strict procedural compliance and is not driven by equitable considerations. Practical point: if circumstances change (for example, a sale), notify the authority immediately and reassess eligibility to avoid an unexpected clawback.

Third, there is no broad, free-standing discretion for authorities to waive CIL by withdrawing Liability Notices under Regulation 65(7). The power to withdraw a notice does not extinguish the underlying tax liability, and any discretion sits within the tightly framed statutory code, including exceptional relief and enforcement choices. This decision calls into question the power under which some local authorities have been undertaking discretionary CIL reviews under Regulation 65(7). Practical point: build your approach around the regulations that actually grant relief, not around informal expectations of discretion. 

Fourth, perceived “double recovery” risks must be managed through the mechanisms Parliament provided. Parties should actively use liability transfers (Regulation 32) and abatement/crediting between successive permissions (Regulation 74B), and, where relevant, contract for purchasers to secure abatement before commencement. Failure to do so can leave the original self-builder exposed. Practical point: build abatement and liability-transfer obligations into sale contracts and check commencement triggers on day one.

The judgment underscores that CIL functions like a tax: it is a precise, rules-based system that rewards timely procedural steps and leaves little room for ex post equitable relief. As practitioners our focus is on helping clients map the procedural steps early so avoidable CIL exposure is not baked in.

For more information and advice on CIL, contact our expert Planning team by email or call +44(0)3333 231580.