Free tool
Will you pay the Community Infrastructure Levy?
Whether the levy is likely, which exemption applies, and which forms to send before work starts.
About this tool
The Community Infrastructure Levy (CIL) is a charge councils can set on new building. Answer a few questions about your project. The checker tells you whether the levy is likely to apply, which exemption could remove it, and the forms and deadlines that decide whether you keep it. Most householders pay nothing, but an exemption claimed after work starts is lost.
- Jurisdiction
- England
- Law checked
- 29 September 2026
- Tool version
- 1.1
Made and maintained by Parallel Architecture, a director-led architectural design practice working from Bristol and Brighton. Each rule is checked against the legislation itself and cited where it is applied. How we write the guides and tools.
General guidance on the law in England from the answers you enter, not advice on your project. Website terms.
What this checker is doing
It follows the Community Infrastructure Levy Regulations 2010 in the order they apply.
- Is there a charge at all? A council can collect CIL only once it has adopted a charging schedule, its published list of CIL rates. In London the Mayor's CIL applies everywhere.
- Is the project minor development? Under 100 square metres of gross internal area, the floor area measured to the inside face of the external walls, that creates no new home is minor development and pays no CIL (regulation 42(1) and (2)).
- Does an exemption fit? The exemption for residential extensions or annexes, for the home you own and live in (regulation 42A), or the self-build exemption, for a home you build to live in (regulations 54A to 54D).
- Is the timing still right? An exemption claim must reach the council before commencement, the legal start of work, and lapses if work starts before the council decides (regulations 42B(2) and (3), 54B(2) and (3)).
- Which notices apply? Where CIL applies, a commencement notice must tell the council the day work will start, unless the project is minor development or an exemption for a residential extension has been granted (regulation 67(1A)). Permitted development, work done without a planning application, that CIL applies to also needs a notice of chargeable development before it starts (regulation 64).
- A rough figure, only if you give the rate: gross internal area times the council's rate for that year. The council's notice of the charge, the liability notice, is the only figure that counts.
Key rules
Whether CIL applies
A council can charge the Community Infrastructure Levy (CIL) only once it has adopted a charging schedule, its published list of CIL rates. In London the Mayor's CIL applies in every borough, on top of any borough CIL.
An extension or other building with under 100 square metres of gross internal area that creates no new dwelling is minor development and pays no CIL (CIL Regulations 2010, regulation 42(1)).
Development that creates a new dwelling, including a residential annex, is never minor development, whatever its size (regulation 42(2)).
Gross internal area (GIA) is the floor area measured to the inside face of the external walls, on every floor, including garages and basements.
Floorspace in an existing building that has been in lawful use for six months in a row within the three years before planning permission can be deducted from the charge (Schedule 1).
Exemptions and relief
An owner who lives in the house as their main home can claim the exemption for residential extensions with Form 9, or the exemption for residential annexes with Form 8 (regulation 42A).
A person building a home to live in as their main home can claim the self-build exemption with Form 7, part 1, after assuming liability for CIL with Form 2 (regulations 54A and 54B).
An exemption claim must be received by the council before development commences, and the claim lapses if work starts before the council has decided (regulations 42B(2) and (3), and 54B(2) and (3)). No work should start on site, including demolition or site clearance, until the council's written decision arrives.
Within six months of the compliance certificate, a self-builder sends Form 7, part 2, with the evidence it asks for, and must live in the home as their main residence for three years, or the exemption is clawed back (regulations 54C and 54D).
The exemption for a residential annex can be clawed back if, within three years, the annex is let, or the house or the annex is sold on its own, and the council must be told (regulation 42C).
Affordable homes may qualify for social housing relief, claimed before work starts with Form 10 (regulation 49).
Notices and deadlines
Where CIL applies, a commencement notice (Form 6) must reach the council no later than the day before development commences (regulation 67(1)).
No commencement notice is needed for minor development, or once the exemption for a residential extension has been granted (regulation 67(1A)).
Permitted development that CIL applies to needs a notice of chargeable development (Form 5) before work starts (regulation 64).
A missed commencement notice can bring a surcharge of 20% of the charge, or £2,500 if that is lower (regulation 83(1)). For an annex or self-build exemption, where the liability notice was issued on or after 1 September 2019, a missed notice brings a surcharge of 20% of the charge the exemption removed, or £2,500 if that is lower, rather than the loss of the exemption (regulation 83(1A)).
Whoever will pay should assume liability with Form 2 before work starts, so that the liability notice, the council's notice of the charge, goes to them. The liability notice is the only figure that counts.