How often can a landlord increase rent?

Once every twelve months, by Section 13 notice, giving at least two months’ notice.

Since 1 May 2026 that is the only route. Rent review clauses in the tenancy agreement no longer bite, and neither does agreeing a rise informally in a way that sidesteps the notice.

The increase has to be to market rent, meaning what the place would let for if you advertised it today. The tenant can take it to the First-tier Tribunal, which cannot award more than you asked for and cannot backdate.

A large increase used to force somebody out is treated as what it is.