Section 13 Rent Increase Notice Calculator (RRA 2025)

Under the Renters' Rights Act 2025, which came into force on 1 May 2026, landlords must give tenants a minimum of two clear calendar months' written notice before a rent increase can take effect. This applies to all assured periodic tenancies in England, regardless of whether rent is paid weekly, fortnightly, monthly, or quarterly. You must serve the prescribed Form 4A — not the old Form 4. Using the wrong form voids the notice entirely and requires you to start the two-month notice period again.

Yes, significantly. Under the pre-RRA 2025 regime, the Section 13 notice period mirrored the rental period — one month for monthly tenancies, one week for weekly tenancies. The RRA 2025 standardised the minimum at two full calendar months across all assured periodic tenancies, regardless of payment frequency. It also replaced the old Form 4 with a new prescribed document, Form 4A, which reflects the new statutory rules. Serving the old Form 4 on a private sector tenancy after May 2026 renders the notice legally void.

Rent can be increased a maximum of once every 52 weeks under the RRA 2025. The 52-week clock starts from the date the last increase took effect — or from the tenancy start date for the very first increase. All contractual rent review clauses (CPI-linked uplifts, annual step increases, index-linked adjustments) are now legally void. The Section 13 process using Form 4A is the only mechanism available to private sector landlords and letting agents for increasing rent. There are no exceptions, regardless of the tenancy agreement's terms.

A Form 4A notice that specifies an effective date before the 52-week minimum interval has elapsed is legally invalid. The tenant has no obligation to pay the increased amount, and the entire process must be restarted by serving a new Form 4A with a legally compliant effective date. Under the RRA 2025, backdating is strictly prohibited — the new rent can only apply from the effective date on a valid, correctly served notice. Any delay results in a permanent loss of the additional rental income for the period of the error.

Yes. Tenants have a statutory right under Section 14 of the Housing Act 1988 to apply to the First-tier Tribunal (Property Chamber) to challenge a proposed rent increase if they believe it exceeds the prevailing open market rent for a comparable property. The application must be made before the proposed effective date on the Form 4A. While the challenge is in progress, the increase is paused. Crucially, if the Tribunal later confirms the increase, the landlord cannot backdate it — the new rent applies only from the date of the Tribunal's decision, potentially months after the original effective date.