The 18-month rule (section 20B): late service charge bills explained

England and Wales · Law checked 24 October 2026 · Not legal advice

Free tool: 18-month rule checker. Enter the invoice date and the date you were billed or notified to see if the 18-month limit appears to be breached.

Section 20B of the Landlord and Tenant Act 1985 says that if any costs in a service charge were incurred more than 18 months before the demand was served on you, you are not liable for that part, unless within those 18 months you were notified in writing that the costs had been incurred and that you would have to contribute (a "section 20B(2) notice").

When is a cost "incurred"?

Generally when the landlord is invoiced or pays, not when the work is done (Court of Appeal, Burr v OM Property Management [2013] EWCA Civ 479). So the date on each invoice and payment matters. Get them under section 22.

Traps to watch

• On-account (budget) demands and later balancing charges can complicate the analysis. If the on-account sums already covered the cost, the rule may not bite.
• A valid 20B(2) notice must say that costs have been incurred and that you will be required to contribute. A vague "costs may increase" note is unlikely to be enough.
• Reserve fund contributions are payments into a fund, not necessarily costs incurred, so get advice.

How to use it

List each late item with its invoice date, ask for a copy of any 20B(2) notice, and ask for the items to be removed. Our kit includes a ready-made section 20B letter. For older years generally, see how far back you can challenge.

Questions