Tenancy Form 4: Landlord's Notice Proposing a New Rent

Form 4 — Notice proposing a new rent under an assured periodic tenancy — is the prescribed statutory form for landlord-initiated rent increases under section 13 of the Housing Act 1988 as amended by the Renters' Rights Act 2025. From 1 May 2026, Form 4 is the only lawful mechanism for rent increases. Minimum 2 months' notice (extended from 1 month under the RRA 2025), maximum once per 52 weeks. The tenant can refer the proposed rent to the First-tier Tribunal — and crucially, the Tribunal can no longer set a rent higher than the landlord proposed (RRA 2025 reform). This page covers when Form 4 is used, what it contains, the tenant challenge route, a worked example, and the common landlord errors.

What Form 4 is

Form 4 — formally "Notice proposing a new rent under an assured periodic tenancy of premises situated in England" — is the prescribed statutory form for a landlord proposing a rent increase to a tenant under section 13 of the Housing Act 1988. From 1 May 2026, the Renters' Rights Act 2025's reforms have made Form 4 the only lawful route for rent increases in the post-reform tenancy framework. A landlord can no longer rely on rent review clauses in tenancy agreements, mid-tenancy rent agreements, or any other contractual mechanism — every rent increase must use Form 4 service under section 13 as amended.

The position before 1 May 2026 was different. Section 13 was historically the route for increasing rent on statutory periodic tenancies (those that had become periodic at the end of a fixed term) where the tenancy agreement contained no rent review mechanism. Where the agreement included a contractual rent review clause, the clause typically operated of its own force and section 13 was unnecessary. The RRA 2025 abolished fixed terms and converted all assured tenancies to periodic, eliminating the rent review clause as a viable route — Form 4 / section 13 is now the universal mechanism.

Form 4 is short and procedurally straightforward, but the procedural requirements that surround it are detailed and unforgiving. A defective Form 4 produces an invalid rent increase, which has knock-on effects on rent collection, possession proceedings, and the tenant's right to challenge the increase. Getting the form right matters.

When Form 4 can be used

Under the post-1 May 2026 framework, Form 4 / section 13 applies to all assured tenancies (which are all now periodic). The key requirements for valid use:

• Minimum 2 months' notice from the date of service to the date the new rent takes effect. The notice period was 1 month before the RRA 2025; the Act extended it to 2 months as part of the broader rebalancing of landlord-tenant timelines.
• No more than once in any 52-week period. A landlord can only use Form 4 once every 52 weeks — repeated use to attempt sequential increases is invalid. The 52-week clock runs from the date of the previous Form 4, not from the date the previous increase took effect.
• The new rent takes effect at the start of a period of the tenancy. Rent typically falls due monthly; the new rent applies from the start of the next monthly period after the end of the 2-month notice.
• Form 4 must be in the prescribed form. The Government has issued an updated Form 4 reflecting the RRA 2025 changes; using the old form is not valid for post-1 May 2026 increases.

A Form 4 served correctly takes effect on the specified date unless the tenant successfully refers the proposed rent to the First-tier Tribunal (Property Chamber) before that date. Where the tenant does refer, the Tribunal determines the open market rent for the property and either confirms the landlord's figure, sets a different figure, or (in some cases) rules the proposed rent below market and confirms it.

What Form 4 contains

The prescribed Form 4 contains:

• Names and addresses of the landlord and tenant.
• The address of the property.
• The current rent per week or per month.
• The proposed new rent per week or per month.
• The date from which the new rent is proposed to take effect (at least 2 months from the date of service).
• The tenant's rights — including the right to apply to the First-tier Tribunal to challenge the proposed rent.
• Information about the Tribunal procedure — how to apply, what the Tribunal considers, the deadline for application.
• Signature of the landlord (or agent acting on behalf of the landlord).

Where the landlord uses an agent, the agent's name and contact details should be included alongside the landlord's details. The form should be served on the tenant by post (recorded delivery is the safest method), in person, or in any other manner permitted by the tenancy agreement.

Tenant challenge — referring to the Tribunal

The tenant has the right to refer the proposed rent to the First-tier Tribunal (Property Chamber) before the date the new rent takes effect. The Tribunal:

• Determines the "open market rent" the property would command on a new tenancy at the date of the proposed increase.
• Considers comparable evidence — rents on similar properties in the same area.
• Disregards any element of the rent attributable to the tenant's improvements or the tenant's particular circumstances.
• Substitutes its determination for the landlord's proposed figure.

Under the RRA 2025, an important reform is the rule that the Tribunal cannot set a rent higher than the landlord's proposed figure. Before the RRA 2025, the Tribunal could in principle determine a market rent above what the landlord had asked for — meaning that tenants who challenged risked ending up worse off. The RRA 2025 capped the Tribunal's determination at the landlord's proposed figure, removing that downside risk and making rent challenges more attractive to tenants.

In practice, more rent challenges are now expected. Tenants who consider their landlord's proposed increase above market can refer with no risk of ending up paying more than the proposed figure. Landlords proposing aggressive increases face increased likelihood of Tribunal challenge.

Form 4 in practice — a worked example

A landlord wishes to increase the rent on a property currently let at £1,200 per month to £1,350 per month. The current rent has been in place for 18 months. The tenant's rent date is the 1st of each month.

Step 1. Confirm 52 weeks have passed since any previous Form 4. If yes, Form 4 can be used.

Step 2. Prepare Form 4 with the current rent (£1,200), the proposed rent (£1,350), and an effective date at least 2 months in the future at the start of a rent period. If the form is served on 15 June 2026, the earliest valid effective date is 1 September 2026 (15 August would fall short of 2 months; 1 September is the next rent date that is at least 2 months after service).

Step 3. Serve Form 4 on the tenant by recorded delivery, with the date of service documented.

Step 4. If the tenant does not refer the rent to the Tribunal before 1 September 2026, the new rent of £1,350 takes effect from that date. The tenant pays £1,350 from 1 September onwards.

Step 5. If the tenant refers to the Tribunal, the Tribunal determines the market rent. If the Tribunal finds the market rent is £1,250, the new rent is £1,250 — not the £1,350 proposed. If the Tribunal finds the market rent is £1,400, the new rent is still capped at the £1,350 proposed (the post-RRA 2025 cap).

Common errors

1. Using a rent review clause instead of Form 4

Pre-1 May 2026, a tenancy agreement might include a clause providing for annual rent review by reference to RPI or a specified percentage. Such clauses no longer operate post-RRA 2025; every rent increase must use Form 4 / section 13. Landlords relying on rent review clauses produce unenforceable rent increases.

2. Insufficient notice period

The minimum is 2 months from the date of service to the date the new rent takes effect. Calculating from the wrong date — using "2 months' notice" loosely when the actual notice is shorter — invalidates the form. The increase is unenforceable; the old rent continues until a fresh, valid Form 4 is served and runs its full notice period.

3. Increases more often than once per 52 weeks

A landlord cannot serve a fresh Form 4 within 52 weeks of the previous one. A landlord who serves Form 4 in January 2026 and then attempts a second Form 4 in October 2026 produces an invalid second notice — the 52-week clock has not yet run.

4. Wrong effective date

The new rent must take effect at the start of a period of the tenancy. For a monthly tenancy with rent due on the 1st, the new rent must take effect on the 1st of a month — not mid-month. Specifying an effective date that is not a rent period start invalidates the form.

5. Using the pre-RRA 2025 form

The Government issued an updated Form 4 reflecting the RRA 2025 changes. Using the older version of the form (with 1-month notice period and pre-cap Tribunal text) is invalid for post-1 May 2026 service.

Authoritative sources

• Housing Act 1988, section 13 — as amended by the Renters' Rights Act 2025.
• Renters' Rights Act 2025.
• Government Form 4 download.
• Our Renters' Rights Act 2025 guide.
• Our rent management guide.