Community Infrastructure Levy (CIL) — what it is, who pays it, and how to avoid paying more than you owe

CIL is a tax on development that catches buyers and developers by surprise more than almost anything else in planning. It is not always disclosed upfront. It runs with the land. And if you miss the notice requirements when you start development, you can lose your right to relief and be charged the full amount — often tens of thousands of pounds.

What CIL is

The Community Infrastructure Levy was introduced under the Planning Act 2008. It allows councils to charge developers a fixed rate per square metre of new floor space to fund local infrastructure — roads, schools, parks, drainage. Not all councils have a CIL charging schedule. Those that do set their own rates, which vary significantly between authorities and sometimes between different parts of the same authority.

What development is liable

New dwellings including self-build homes where relief is not claimed. Extensions to existing dwellings that create additional gross internal floor space of 100 square metres or more. Changes of use that create new dwellings. Most extensions under 100sqm and householder permitted development works are exempt from CIL.

Exemptions and reliefs — what you may not owe

Self-build relief: if you are building or extending your own home, you may qualify for relief eliminating or substantially reducing the CIL liability — but this must be claimed before development commences. Charitable development is exempt. Vacant building credit: redeveloping a vacant building may give a credit against the CIL liability based on the floor space of the vacant building.

The commencement and disclosure traps

CIL relief must be claimed before development commences. Starting work on site — even minor preparatory works — before claiming relief can result in the full CIL liability falling due with no right to relief. Sellers are not always required to proactively disclose a CIL liability — a property sold with the benefit of a planning permission may carry a CIL liability that the buyer discovers only when they start development.

Your planning record contains more than most people realise

Standard searches check the public register. We go further — querying live portals, blocked legacy systems, pre-merger authority databases, committee PDF archives, Land Registry title constraints, and comparable decisions across your postcode cluster. What we retrieve determines what you know before you build, buy, or appeal.

Full portal extraction — including blocked and legacy systems
Enforcement record search across all relevant authorities
Committee PDF archive mining — officer reports and vote records
Land Registry title analysis — covenants, conditions, access rights
Postcode cluster — comparable decisions approved, refused, withdrawn
Strategic direction — what the data means for your specific position
Get your planning intelligence report — from £149 →
No payment upfront · We scope the report first · 48hr delivery · Any UK property
Related guides
Planning application fees in EnglandSection 106 agreements — what they mean for buyersWhat conveyancing searches miss about planning historyPlanning conditions that bind future owners
← All planning guides