When submitting a planning application, applicants must provide additional information so the local planning authority can determine whether the CIL applies and calculate any charge.

A CIL Additional Information form must be submitted alongside the planning application, detailing existing and proposed floorspace. This enables the authority to assess CIL liability and should be included as a supporting document for online applications.

Once planning permission is granted, the authority will issue a Liability Notice confirming whether CIL is payable and the amount due. Before development starts, the liable party must submit an Assumption of Liability form, and any changes to liability must be formally notified.

CIL becomes payable on commencement of development. A Commencement Notice must be submitted before works begin; failure to do so can result in the loss of any exemptions or reliefs and may trigger surcharges or the full levy becoming payable.

Accurate and timely submission of all required forms is essential to avoid penalties and ensure compliance with CIL regulations.