Challenging a Form 4A Rent Increase at the FTT Property Chamber: The New Rules From 1 May 2026

Last updated: 11 May 2026

Quick Answer

From 1 May 2026, all rent increases on assured tenancies in England must use the new Form 4A under Section 13 of the Housing Act 1988. Tenants who consider the increase above the open-market rent can apply to the First-tier Tribunal (Property Chamber) to determine the rent. The application fee is £47, the tribunal can only revise the rent down (never up beyond the figure proposed in the notice), and the old rent continues to be payable until the tribunal makes its determination. For landlords, the procedural margin for error has tightened sharply; for tenants, the application carries almost no downside.

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The Single Most Important Change

For thirty-eight years, Section 13 of the Housing Act 1988 has been the statutory route for increasing rent on a periodic assured tenancy. The mechanism is simple: serve the prescribed notice, wait the two-month notice period, then the new rent takes effect.

Three things changed on 1 May 2026.

First, the form changed. Form 4A replaces the old Form 4. The new form has a different field-numbering scheme and includes new prescribed information that landlords have to give to the tenant — including a plain-English explanation of the tribunal challenge route.

Second, the tribunal can no longer revise rent upwards. Under the old regime, the tribunal could set the rent at whatever it determined to be the open-market figure, even if that was higher than the landlord's proposed figure. Under the Renters' Rights Act 2025, the tribunal can only confirm the landlord's proposed rent or reduce it. The risk of a "boomerang" upward determination is gone.

Third, the £47 tribunal fee was confirmed by the Government in April 2026 in advance of the Renters' Rights Act commencement. The Government's stated intention is to make the tribunal genuinely accessible to litigants in person, and £47 was chosen as a low fee that nonetheless deters frivolous applications. The fee figure should be checked against the current FTT fees schedule on gov.uk before applying. Fee remission under EX160 is available for tenants on low incomes.

The combination of these three changes — clearer form, no upward risk, low fee — means tenants now have very little reason not to apply if the proposed rent exceeds the market figure. Landlord groups have been pre-warning their members of an application surge throughout May and June 2026 (landlordknowledge.co.uk, retrieved 2026-05-11).

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How Section 13 Actually Works

Section 13 of the Housing Act 1988 (as amended by the Renters' Rights Act 2025) sets the framework. The landlord serves the prescribed notice — now Form 4A — specifying the proposed new rent and the date it will take effect.

The notice has to give:

• The current rent
• The proposed new rent
• The date the new rent will take effect (at least two months after service, on a date that aligns with the rent period)
• Information about the tenant's right to refer the matter to the tribunal

The tenant has, in practice, until the day before the new rent is due to take effect to make a tribunal application. If they apply in time, the old rent continues until the tribunal decides. If they do not apply, the new rent takes effect on the proposed date.

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The "Twelve-Month Rule"

The Renters' Rights Act 2025 introduced a hard limit: the landlord can serve only one Form 4A every 12 months. This codifies what was sensible practice under the old regime, and it is the rule landlords most often trip on.

If your tenant moved in on a periodic tenancy starting 1 March 2026, and you served a Form 4A on 1 May 2026, the next valid Form 4A cannot be served before 1 May 2027. A premature notice is void.

The 12-month period runs from the date of the notice, not from the date the rent took effect.

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The Tribunal's Job

The tribunal's role under Section 14 of the Housing Act 1988 is to determine the open-market rent for the property — what a willing tenant would pay for the property on the open market under a new assured tenancy on the same terms as the existing tenancy. This is a market-rent test, not a "fair rent" test (the old Rent Act 1977 framework is gone for assured tenancies).

The panel comprises a legally qualified chair and (usually) an RICS-qualified valuer member. The valuer member brings their own knowledge of the local rental market to the table. This is not a court applying evidence neutrally — it is a specialist tribunal bringing expertise to bear.

The tribunal can:

• Confirm the proposed rent
• Reduce the proposed rent to its determination of the open-market figure
• Reduce the rent below the existing rent if the open-market rent is below what you currently pay — under Section 14 (as amended by the Renters' Rights Act 2025) the tribunal sets the lower of the proposed rent and the open-market rent, with no floor at the existing rent

The tribunal cannot:

• Set a rent above the figure proposed in the Form 4A (new from 1 May 2026)
• Change the other terms of the tenancy (only the rent figure is at large)

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What Each Side Should Do

The Landlord

If you are serving a Form 4A:

• Get the form right. Use the prescribed Form 4A from the gov.uk catalogue page. Do not improvise. A defective Form 4A is void.
• Calculate the new rent against comparable market evidence. Tessa Shepperson at Landlord Law has emphasised that the days of "stab in the dark" rent increases are over — a tenant can now appeal for £47, and the tribunal will scrutinise the figure (landlordlawblog.co.uk, retrieved 2026-05-11). Pick a figure you can justify.
• Mind the 12-month rule. Check the date of your last Form 4A. If you served one in the previous 12 months, you cannot serve another.
• Mind the deposit-protection point. Deposit-protection compliance is not a precondition to a Section 13 notice (unlike a Section 8 possession notice). But if you are also contemplating possession action, the deposit point will bite there.
• Prepare for a possible challenge. If the tenant applies to the tribunal, you will need to put forward comparable evidence supporting your figure. Start gathering it now, not when the application lands.

The Tenant

If you have just received a Form 4A:

• Read it carefully. Check the date of service, the proposed rent, the effective date, and the prescribed information about your tribunal rights.
• Decide whether to challenge. Is the proposed rent above what similar properties in your area let for? Search Rightmove, Zoopla and OpenRent for comparable lettings. A rough rule: if the proposed rent is more than 10% above the median asking rent for similar properties, the application has merit.
• Apply in time. The deadline for an application is the day before the new rent would take effect — in practice, allow at least three working days for the tribunal to receive the application. Late applications are not accepted.
• Use the FTT's prescribed rent-determination application form. This is the prescribed application form. The fee is £47 (or £0 with EX160 remission).
• Keep paying the existing rent in the meantime. The old rent continues until the tribunal decides. Stopping rent during the application is a separate breach of contract and weakens your position.

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The Application Itself

The FTT's prescribed rent-determination application form is short. It asks for:

• The address of the property
• The date the tenancy started
• The current rent
• The proposed new rent (with the Form 4A attached)
• A brief statement of why the tenant disputes the proposed rent
• The tenant's evidence of comparable rents

The tribunal usually lists the case for a paper determination first (decided on documents) unless either party asks for an oral hearing. An oral hearing is more common for properties where the condition or unusual features make a paper determination harder. Either party can ask for an oral hearing as of right.

The tribunal lists for hearing within four to six months of application in normal conditions. Listings may slip in the May–July 2026 application surge.

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What the Tribunal Will Look At

The valuer member of the panel will be looking at:

• Comparable lettings. Properties of similar type, size, location and specification let in the previous 12 months. Five to ten good comparables is the target.
• Asking rents. Rightmove, Zoopla, OpenRent listings are useful as context but the tribunal places more weight on agreed lettings than asking prices.
• Condition. Disrepair, mould, outdated kitchens and bathrooms reduce the open-market rent. Visible condition matters; the tribunal members may view the property.
• Specification. Furnished or unfurnished, white goods included, garden, parking, EPC rating.
• Tenure-specific factors. Pets allowed, length of tenancy, any tenant-side breach history.

Falcon Chambers' commentary on Property Chamber valuation practice is the most authoritative practitioner source for how panels weigh these factors (falcon-chambers.com, retrieved 2026-05-11).

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The Form 4A Field Map

The new Form 4A contains a numbered set of prescribed fields. The most important traps are:

• Proposed new rent. Has to be expressed as a figure with the rent period (per calendar month, per week). Mixed-up rent periods make the notice void.
• Effective date. Has to be at least two months after service (Housing Act 1988 s.13 as amended by the Renters' Rights Act 2025 s.6), and aligned to the rent period. Off-by-one errors here are the most common defect.
• Current rent. Has to match the figure currently being paid. If the landlord has been collecting a rent that is different from the contractual rent, the form should show the rent actually being paid.
• Landlord's signature and date. A scanned signature is acceptable but the date has to be the actual date of signing, which is also the date for the 12-month clock.

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Worked Example

A two-bedroom flat in south London. Current rent £1,800 per calendar month. The landlord serves a Form 4A on 5 May 2026 proposing £2,150 per month with effect from 5 June 2026 — a 19% increase.

The tenant looks on Rightmove and finds eight similar two-bed flats within half a mile, advertised at £1,900–£2,050 per month, with two recently agreed at £1,950 and £2,000.

The tenant applies to the tribunal on 18 May 2026, paying £47. They attach screenshots of the comparables, photographs of the flat showing some condition issues, and a brief statement explaining the discrepancy.

The tribunal lists for a paper determination on 12 September 2026. The valuer member assesses the comparables and the condition. The tribunal determines the open-market rent at £1,975 per calendar month. Under Section 14 as amended by the Renters' Rights Act 2025, the determined rent takes effect from the start of the next rent period after the determination (not backdated to the notice date), unless the tribunal directs a later date for undue hardship.

The tenant's net position: a rent of £1,975 rather than £2,150. The £175 monthly saving — £2,100 over a year — substantially exceeds the £47 application fee. The landlord cannot serve another Form 4A before 5 May 2027.

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When Not to Apply

The application is not always the right move. Reasons to think carefully:

• The proposed rent is genuinely at or near market. If the landlord's figure looks roughly right, the application is unlikely to succeed and the tribunal cannot reduce the rent below market.
• Your tenancy is at risk for other reasons. A landlord considering Section 8 possession might pause if a tribunal application is on foot, but a determined landlord will press ahead.
• You have plans to leave anyway. If you are moving out within the next few months, the application may not be worth the friction.

For most tenants facing a sharp increase, the math is straightforward: a successful application that knocks £100 a month off the rent saves £1,200 a year. The fee is £47. The downside is essentially zero.

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What to Put in the Tribunal Bundle

For an application bundle, prepare:

• The Form 4A as served
• The tenancy agreement
• Bank statements showing the current rent being paid
• Photographs of the property, dated, showing condition
• Comparable lettings — printouts from Rightmove, Zoopla and OpenRent
• A brief witness statement from the tenant
• Any correspondence with the landlord about repairs or condition
• The application form the FTT's rent-determination application form (from GOV.UK / the Property Chamber)

For the landlord responding to the application, the bundle adds:

• A landlord witness statement
• The landlord's own comparable evidence (often a letting agent's report)
• Any improvement evidence (recent works to the property that justify the higher rent)
• The condition history

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BundleCreator's tenancy-variation templates at /tenancy-variation include the Form 4A landlord template, the tenant's tribunal application particulars, and the comparable evidence schedule, all PD27A-aligned for the FTT bundle.

Nothing in this article is legal advice or a substitute for it. The information here describes the law as it stands at the date shown; the law and procedure may change. For free regulated advice, contact Citizens Advice, Shelter England, your local Law Centre, or the Housing Loss Prevention Advice Service (which is available without charge to any tenant served a Section 8 notice). The Tribunal Procedure (First-tier Tribunal) (Property Chamber) Rules 2013 (as amended) apply to rent-determination applications.