Rent Increase Checker (Form 4A)
Check whether your Section 13 rent increase notice is valid under the Renters' Rights Act 2025. Enter three dates and get an instant valid/invalid verdict plus the earliest date your increase can lawfully take effect. Free, no signup.
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Is your rent increase notice valid?
A rent increase on a periodic assured tenancy in England is only valid if it passes three tests: it is served on Form 4A, it gives the tenant at least 2 months' notice, and it takes effect at least 12 months after the last increase (or the tenancy start). Fail any one and the tenant can lawfully keep paying the old rent. This free checker takes your three dates and tells you instantly whether the notice stands, and if not, the earliest date a valid increase can take effect.
The three rules this checker tests
- Form 4A only. From 1 May 2026 the prescribed Section 13 notice is Form 4A, "Landlord's notice proposing a new rent", published on the gov.uk assured tenancy forms page. The old Form 4, a letter, or an email is not a valid notice. See the how to raise rent guide for the full process.
- At least 2 months' notice. Gov.uk guidance states you must give the tenant the completed form at least 2 months before you want the rent increase to start.
- Once a year at most. The same gov.uk guidance confirms rent can only be increased once a year, not in the first year of the tenancy, and not until at least a year after the last increase took effect. The statutory mechanism is Section 13 of the Housing Act 1988 as amended by the Renters' Rights Act 2025.
Two things to check yourself
Rent period alignment. Under section 13(2) of the Housing Act 1988, the new rent takes effect at the beginning of a new period of the tenancy. If rent is due on the 1st of the month, set the effective date to a 1st. The checker cannot validate this because it does not know your rent due date, so confirm it before serving.
Open market rent. The proposed figure must reflect what the property would fetch if re-let today. The tenant can refer the increase to the First-tier Tribunal before the effective date, and the Tribunal can only set the rent at or below your proposed figure, so pitch it at a defensible market level with comparable evidence saved. The Form 4A guide covers building an evidence file.
Rent review clauses are void
Under the Renters' Rights Act 2025 you cannot rely on a rent review clause in the tenancy agreement: gov.uk confirms that an increase taking effect after 1 May 2026 under a rent review clause does not apply. If the tenant genuinely agrees a new rent in writing you can record that by agreement; for any compelled increase, Form 4A under Section 13 is the only route.
This checker covers assured periodic tenancies in England and is practical information, not legal advice. Rules reflect the law in force as of July 2026. For your specific situation, consult a qualified solicitor.
Frequently Asked Questions
How much notice do I need to give for a rent increase in 2026?
At least 2 months. Under Section 13 of the Housing Act 1988 as amended by the Renters' Rights Act 2025, you must give the tenant the completed Form 4A at least 2 months before the date the new rent takes effect. A notice giving less than 2 months is invalid and must be re-served. Source: gov.uk guidance for landlords on rent increases.
How often can a landlord increase rent under the Renters' Rights Act 2025?
Once a year at most. The new rent cannot take effect until at least 12 months after the last increase took effect, and you cannot increase the rent in the first year of the tenancy. Serving a notice with an effective date inside that 12-month window makes the notice void. Source: gov.uk guidance for landlords on rent increases.
Can I still use a rent review clause to raise the rent?
No. Rent review clauses are void for assured tenancies under the Renters' Rights Act 2025. The only way to compel a rent increase the tenant has not voluntarily agreed is a Section 13 notice on Form 4A, the prescribed form published on gov.uk for use from 1 May 2026.
What happens if my rent increase notice is invalid?
The tenant can legally ignore it and keep paying the old rent, and if the increase is referred to the First-tier Tribunal the Tribunal has no power to set a new rent on a defective notice. You must fix the defect and re-serve, which restarts the 2-month notice clock. Use the checker above to catch date errors before you serve.
Can the tenant challenge a valid rent increase?
Yes. The tenant can refer the proposed rent to the First-tier Tribunal before the effective date if they believe it exceeds the open market rent. The increase is suspended until the Tribunal decides, and under the Renters' Rights Act 2025 the Tribunal can only set the rent at or below the figure on your Form 4A, never above it.