Quick Answers
What form do I use?
Form 4 (Notice proposing different rent under an assured periodic tenancy), available free from gov.uk. Use the current version. An outdated form invalidates the notice and you will need to start again, losing the full notice period.
How much notice is required?
At least one rental period. For monthly tenancies, that is one calendar month. The notice must expire on the last day of a rental period, and the new rent cannot take effect within 12 months of the last rent being set or changed.
Can the tenant refuse the increase?
The tenant cannot simply refuse. They can challenge the proposed amount at the First-tier Tribunal before the notice takes effect. The Tribunal sets a market rent, which is binding on both parties. If the tenant does not challenge before the effective date, the new rent applies automatically.
The process: serve Form 4 giving at least one month's notice, expiring on the last day of a rent period, proposing the new rent from a date at least 12 months after the last increase. If the tenant does not refer the matter to the Tribunal before the effective date, the new rent takes effect automatically. If they do refer it, the Tribunal determines a market rent and that figure is binding.
The most common error: landlords proposing a new rent that would take effect before 12 months have elapsed since the current rent was set. Alternatively, serving the notice with insufficient notice period. Both errors require the notice to be re-served from scratch, delaying the increase by the full notice period again. Getting the dates right before serving is the single most important step.
Key Takeaways
Section 13 is the exclusive route, without exception
The Renters' Rights Act removed all alternative mechanisms. A letter proposing a higher rent, an email the tenant replies to saying "OK", a new tenancy agreement at a higher figure, a clause in the original agreement purporting to allow annual CPI increases: none of these produce a legally effective rent increase in an assured periodic tenancy. Only a correctly served Section 13 notice works.
Rent can only increase once every 12 months
The 12-month gap is calculated from the date the current rent was last set or changed, not from the date of the last notice. A tenancy that started at £1,400 per month on 1 March 2025 cannot have its rent increased before 1 March 2026 at the earliest. A tenancy where rent was determined by the Tribunal in December 2025 cannot be increased before December 2026. The 12-month clock runs from the operative date of the last change, not from any notice.
The tenant's referral to the Tribunal does not block the increase indefinitely
A common landlord misconception is that a tenant who refers the notice to the Tribunal is delaying or refusing the rent increase. What the tenant is actually doing is asking the Tribunal to determine the correct market rent. The Tribunal will set a figure, which may be the same as, higher than, or lower than what the landlord proposed. The process takes some months but produces a binding determination. In the majority of cases it confirms a rent close to the landlord's proposal.
The Tribunal can set a rent higher than the landlord proposed
Landlords who propose a modest increase to avoid a Tribunal challenge sometimes find that the Tribunal, when challenged by the tenant on other grounds, sets a market rent that is actually higher than the notice figure. The Tribunal applies market evidence and is not constrained by the landlord's proposal as a ceiling. Proposing a below-market rent on the assumption it will not be challenged is not always a safe strategy.
Landlords cannot use the Tribunal themselves to push a higher rent
The Section 13 process is tenant-initiated at the Tribunal stage. A landlord cannot refer the matter to the Tribunal themselves to get a higher figure than the tenant is willing to pay informally. The landlord serves the notice, the tenant either accepts it or refers it. If the tenant accepts a below-market notice figure, the landlord is bound by that lower figure until the next 12-month window.
A defective notice has no legal effect and cannot be corrected
If the Section 13 notice is defective (wrong form, insufficient notice period, proposed effective date within the 12-month restriction, or incorrect property details), it has no legal effect. The landlord cannot correct or amend it. A new notice must be served from scratch, restarting the notice period. This is a material cost in time: on a monthly tenancy, an error discovered two weeks into the notice period means starting again and waiting another month.
The Core Rule
Under the Renters' Rights Act, rent in an assured periodic tenancy can only be increased by serving a valid Section 13 notice. There is no other route. This applies from 1 May 2026 to all assured periodic tenancies in the private rented sector in England, whether they were created after the Act came into force or converted from existing fixed-term agreements.
The relevant provisions are in section 13 of the Housing Act 1988, as amended. The notice must be on the prescribed form (Form 4), must comply with the timing requirements, and must be served correctly on the tenant. If any of these requirements is not met, the notice is void.
Agreeing a rent increase by email or letter with the tenant's consent. Issuing a new tenancy agreement at a higher rate. Including a clause in the tenancy agreement for automatic annual increases. Raising rent at the end of a fixed term (fixed terms no longer exist). Inserting a clause allowing increases linked to CPI or RPI. All of these are now legally ineffective in an assured periodic tenancy. The only valid route is Form 4, served correctly, with the right notice period and the right timing.
What a Valid Section 13 Notice Must Contain
Form 4 has a specific structure and must be completed in full. The following fields are required and errors in any of them can invalidate the notice.
Section 13 Notice — Required Content
The Timing Rules in Detail
The timing of a Section 13 notice is where the majority of errors occur. There are three distinct timing requirements, all of which must be satisfied simultaneously for the notice to be valid.
| Requirement | What It Means and How to Apply It |
|---|---|
| Minimum notice period | At least one rental period must elapse between service of the notice and the proposed effective date. For a monthly tenancy, that is one calendar month. For a weekly tenancy, one week. The notice period runs from the date of service, not the date of writing. If the notice is posted, allow for postal delivery time. Email service is valid if the tenancy agreement permits it or the tenant has agreed to it. |
| Effective date must be the first day of a rental period | The proposed effective date must fall on the first day of a rental period. If rent is paid monthly on the first of each month, the effective date must be the first of a month. If rent is paid on the 15th, the effective date must be the 15th of a month. A notice proposing an effective date mid-period is defective and void. |
| 12-month gap since last increase | The proposed effective date must be at least 12 months after the date the current rent was last set or changed. "Last set" means the date the tenancy started at the current rent, or the date a previous Section 13 increase took effect, or the date a Tribunal determination took effect. Count exactly: 12 calendar months, not "approximately a year". A notice proposing an effective date of 1 June 2026 when the current rent was set on 1 June 2025 is fine; the same notice proposing 1 May 2026 is defective by one month. |
Take the date the current rent was last set. Add 12 calendar months. That is the earliest the new rent can take effect. Then check whether the proposed date is the first day of a rental period and that at least one full rental period of notice has been given from the intended service date. If all three conditions are met on your proposed date, the notice is valid from a timing perspective.
What Happens at the First-tier Tribunal
If the tenant refers the Section 13 notice to the First-tier Tribunal (Property Chamber) before the effective date, the Tribunal determines the market rent for the property. This is the statutory process and it is not adversarial in the way court proceedings are. The Tribunal is not deciding whether the landlord is allowed to increase the rent; it is deciding what the correct market rent is.
Tenant refers the notice
The tenant applies to the First-tier Tribunal before the effective date specified in the notice. The application is made using the Tribunal's online system and costs the tenant a modest application fee. The referral does not suspend the tenancy or the rent payment obligations; the tenant continues paying the current rent until the Tribunal determination takes effect.
Both parties submit evidence
The Tribunal invites both the landlord and the tenant to submit evidence on the market rent. For landlords, this means comparable rental evidence: what similar properties in the same area are achieving on the open market. Rightmove, Zoopla, and letting agent comparables are all admissible. The Tribunal is not interested in the landlord's mortgage costs, maintenance costs, or desired yield; it is interested solely in market evidence.
Hearing or paper determination
Many rent increase cases are determined on the papers without a hearing, particularly where the evidence is clear and both parties have submitted their position in writing. Where there is a significant factual dispute or where the figures are complex, a hearing will be listed. Hearings are informal by court standards; neither party needs a solicitor, though legal representation is permitted.
Tribunal determines the market rent
The Tribunal issues a written determination setting the open market rent for the property. This figure is binding on both parties and takes effect from the date specified in the original Section 13 notice (or a later date if the determination is made after the original effective date). The determined rent applies until the next Section 13 notice is served, no earlier than 12 months later.
New rent takes effect
The new rent is payable from the effective date in the Tribunal's determination. If the Tribunal confirmed a higher figure than the current rent, the landlord does not receive the increase retrospectively for any period the tenant was paying the old rent while the case was pending. The increase runs from the determination date forward.
The Mistakes Landlords Keep Making
The most common error. A landlord whose tenancy started at £1,500 per month on 15 January 2025 who serves a Section 13 notice in November 2025 proposing a new rent from 1 January 2026 has made a defective notice: the new rent would take effect only 11.5 months after the current rent was set. The notice is void. Re-serve with a valid effective date of 15 January 2026 or later.
Form 4 has been updated following the Renters' Rights Act. A notice served on a pre-Act version of the form may be defective. Download the current version from gov.uk immediately before preparing the notice. Do not use a template saved from a previous tenancy. The Tribunal has struck out notices on defective form grounds.
A landlord whose rent is due on the 20th of each month who proposes a new rent from the first of the month has made a defective notice. The effective date must be the first day of a rental period. For a tenancy where rent is due on the 20th, the only valid effective dates are the 20th of any given month.
A notice served on 3 June proposing an effective date of 1 July does not give a full calendar month's notice for a monthly tenancy: there are only 28 days between 3 June and 1 July. The notice period must be at least one full rental period. For a monthly tenancy, serving on 1 June and proposing an effective date of 1 July is exactly one month and is valid. Serving on 3 June requires the effective date to be 3 July or later, which pushes to 1 August to coincide with the rental period start.
A notice saying "rent will increase by 5% to reflect market conditions" is defective. The proposed new rent must be stated as a specific amount in pounds. The tenant must know exactly what they are being asked to pay. A notice that requires arithmetic to determine the proposed rent amount does not comply with the prescribed form.
A landlord who serves a valid Section 13 notice and then, when the tenant says they do not accept the increase, withdraws the notice and tries to negotiate a different figure informally, has wasted the notice. Once a valid notice is served, it either proceeds to the effective date (and takes effect if unchallenged) or goes to the Tribunal. Withdrawing it and starting again loses the notice period and delays the increase further.
Strategic Considerations for Landlords
The Section 13 process is straightforward once you understand it, but it rewards forward planning. A few points worth thinking through before serving any notice.
Propose a genuine market rent, not a negotiating position. The Tribunal applies market evidence. If your proposed rent is at genuine market rate and the tenant refers to the Tribunal, the Tribunal is likely to confirm something close to your figure. If you have pitched high in anticipation of negotiation, you risk a Tribunal determination that is lower than the market rate you actually want, because the comparables you can produce support the lower figure.
Keep comparable evidence before you serve. If the tenant refers the notice, you will need to produce evidence of comparable market rents. Do this before serving, not after receiving the Tribunal's acknowledgement letter. Rightmove and Zoopla current listings, and recently let properties in the same area, are the primary sources. Save the evidence at the time you set the rent; the market will have moved by the time a Tribunal hearing is listed.
Time the notice correctly the first time. Re-serving after a defective notice is a pure delay. If you intend to increase rent from 1 September, work backwards: the notice must be served by 1 August at the latest for a monthly tenancy. The 12-month restriction means the current rent must have been set no later than 1 September of the previous year. Check both before drafting the notice, not after.
Do not be deterred by a Tribunal referral. Many landlords receive a Tribunal referral and assume they have done something wrong or that the process will cost them significantly. Neither is necessarily true. The Tribunal is a low-cost, relatively informal process, and the outcome in most straightforward rent increase cases is a determination that confirms the market rent, which is typically close to what the landlord proposed.
For the broader context of what changed on 1 May 2026, see Periodic Tenancies After the Renters' Rights Act. For how possession works in a periodic tenancy, see Section 8 After the Renters' Rights Act.
Frequently Asked Questions
Serve a Section 13 notice using the current version of Form 4, available from gov.uk. Give at least one rental period's notice. Ensure the proposed effective date is the first day of a rental period and falls at least 12 months after the current rent was last set or changed. If the tenant does not refer the notice to the First-tier Tribunal before the effective date, the new rent applies automatically. There is no other valid mechanism.
Form 4 (Notice proposing different rent under an assured periodic tenancy), available free from gov.uk. Always download the current version immediately before use. Using an outdated form version may invalidate the notice and require it to be re-served from scratch.
The Tribunal determines the open market rent for the property, based on comparable evidence from both parties. The Tribunal's figure may be the same as, higher than, or lower than the landlord's proposed amount. The determination is binding. Most challenges result in the Tribunal confirming a figure close to the landlord's proposal if the proposed rent was genuinely at market rate.
No. The Renters' Rights Act made Section 13 the exclusive route. An informal agreement, a new tenancy agreement at a higher rate, or a clause in the existing agreement for automatic increases are all legally ineffective in an assured periodic tenancy. The only valid mechanism is a correctly served Form 4 notice.
Once every 12 months. The proposed new rent cannot take effect within 12 months of the date the current rent was last set or changed. The 12-month gap runs from the operative date of the last change, whether that was the start of the tenancy, a previous Section 13 increase, or a Tribunal determination.
Managing a rental property and need to raise the rent?
Neon's property management service handles Section 13 notices for landlords across East London and Essex as part of day-to-day management. We get the dates right, use the current form, and manage any Tribunal referral if it arises. At £88, our compliance audit also checks your full landlord compliance position before any notice is served.
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