How to Increase the Rent in 2026: Section 13, Form 4A, and the Rules Landlords Are Getting Wrong

From 1 May 2026, Section 13 (Form 4A) is the only lawful rent increase route. Rent review clauses are gone. Two months' notice required.

Before 1 May 2026, landlords had several routes to a rent increase: a rent review clause written into the tenancy agreement, a mutual agreement with the tenant, or the formal Section 13 statutory notice. Since the Renters' Rights Act 2025 came into force, only one of those routes still works. The others are either invalid or unenforceable — and attempting them does not increase the rent, but can expose you to a civil penalty of up to £7,000.

The only lawful route: Section 13 and Form 4A

To increase rent on an assured periodic tenancy in England, you must serve a Section 13 notice using the prescribed Form 4A, which replaced Form 4 on 1 May 2026. The notice must:

State the proposed new rent amount clearly
Give the tenant at least two months' notice (up from one month under the previous rules)
Specify a start date that falls at the beginning of a new rent period
Propose a start date no sooner than 12 months after the previous increase took effect

Attempting to increase the rent by any other method — a new written agreement proposing a higher figure, or a clause in the tenancy purporting to increase rent automatically — is either invalid or unenforceable.

What no longer works

Rent review clauses are now of no effect. Under the Renters' Rights Act 2025, section 6, any clause in a tenancy agreement that provides for rent increases outside the Section 13 process cannot be relied upon. If your existing tenancy contains a rent review clause, it gives you no legal basis to increase the rent. You must still serve Form 4A.

Informal agreements are similarly ineffective. If you and your tenant agree informally — by text, email, or verbally — on a higher rent, that agreement cannot bind the tenant. They can revert to the existing rent. The only exception is where the tenant agrees to pay less than the amount proposed in a valid Section 13 notice — that lower figure can stand.

The tenant's right to challenge

Tenants can now challenge a proposed rent increase at the First-tier Tribunal (Property Chamber) for a fee of £47. Crucially, the Tribunal can only keep the rent the same or reduce it — previously, if it assessed the market rate as higher than what was proposed, it could increase the rent. That option is gone.

This changes the risk calculation. If you propose significantly above market rate, the tenant can challenge cheaply, the increase is delayed until the Tribunal rules, and the Tribunal may set a lower figure. The Act has made aggressive rent increases more costly for landlords and essentially risk-free to contest for tenants.

The Tribunal assesses the proposed rent against the open-market rate — what a landlord could expect from a new tenant. If it determines the market rate is lower than your proposal, it can set the rent at that lower figure. If the market rate is higher, the Tribunal cannot set it above what you proposed.

The 12-month restriction and timing traps

You can only increase the rent once in any 12-month period. The clock runs from the date the previous increase took effect, not from the date you served the notice.

If the tenant challenges your notice at the Tribunal, the increase is delayed until the Tribunal's decision. That decision date then becomes the new baseline, pushing back when you can next serve. A contested increase can therefore lock your rent at the current level for longer than you planned.

Serving Form 4A correctly

Form 4A is available from GOV.UK. Key points:

Serve on every named tenant individually — one copy to the household is not sufficient
The notice must be in the prescribed form — a letter containing the same information is not valid
Keep proof of service — a dated email with the form attached, or tracked post
The new rent takes effect two months after service, at the beginning of the relevant rent period, unless the tenant challenges it at the Tribunal

What happens if you get it wrong

A notice served without the correct form, with insufficient notice, or with a start date inside the 12-month restriction period is invalid. The tenant does not have to pay the higher amount, and you must re-serve correctly — resetting the clock.

Attempting to enforce a rent increase outside the Section 13 process — by treating an informal agreement as binding, or relying on a rent review clause — can attract a civil penalty of up to £7,000 from the local housing authority.

mypy's rent-increase workflow generates Form 4A pre-filled from your tenancy details, enforces the one-per-12-months rule automatically, and logs proof of service in one place. Try it free for your first two properties.

Frequently asked questions

Can I still use a rent review clause to increase the rent?

No. Under the Renters' Rights Act 2025, rent review clauses in assured periodic tenancies are of no effect. The Section 13 notice (Form 4A) is the only valid route.

How much notice do I have to give for a rent increase?

At least two months. This doubled from one month when the Act came into force on 1 May 2026. The notice must also propose a start date at the beginning of a new rent period.

How often can I increase the rent?

Once in any 12-month period. The clock runs from the date the previous increase took effect, not from when you served the notice.

What happens if my tenant challenges the increase?

The tenant applies to the First-tier Tribunal for £47. The Tribunal determines the market rent — which can only be the same as or lower than what you proposed, never higher. The increase is delayed until the Tribunal decides.

What form do I use for a rent increase?

Form 4A, available from GOV.UK. It replaced Form 4 on 1 May 2026. A letter setting out the same information is not a valid substitute.

Sources

This article is general guidance, not legal advice. Verify your obligations against current GOV.UK guidance or seek professional advice for your circumstances. Last reviewed 2026-07-03.