Form 4A Rent Increase: How to Serve It Under the Renters' Rights Act

Corrected on 2026-06-11: earlier versions of this guide (updated 2026-04-16) said Form 4A was a watermarked preview that "cannot yet be used" and advised "Use Form 4 until then" — correct before Phase 1 commencement, wrong now. The usable Form 4A has been live on the GOV.UK assured-tenancy forms page since 1 May 2026, and GOV.UK now designates Form 4 as the social-housing form ("Do not use this form if the property is rented privately. You should use form 4A."). Also corrected: challenging a rent increase at the tribunal now carries a £47 application fee (see Step 5). Both corrections follow re-verification against the GOV.UK page and SI 2026/485.

What this means for you

A Form 4A rent increase is now the only lawful way to raise the rent on an assured tenancy in England. The Renters' Rights Act 2025 brought this in on 1 May 2026, so as of mid-2026 it is live, not upcoming — the Section 13 / Form 4A route is the one in force today. If you're a landlord or letting agent and you want to put the rent up, you can only do it one way: serve Form 4A on the tenant at least two months before the new rent starts. Form 4A is a specific government document — it's not a letter you draft yourself, and an email or text won't work. Once a year, no more. The tenant can either accept it, agree a different number with you, or ask the First-tier Tribunal to decide.

The rest of this guide covers: where to get the form, what to fill in, how to serve it, and the covering letter most landlords send alongside it.

Form 4A is the new prescribed Section 13 notice landlords use to propose a rent increase on a periodic assured tenancy from 1 May 2026 — replacing Form 4 under HA 1988 s.13 as amended by Renters' Rights Act 2025 s.6. Three quick answers first, then the full process below.

Q: Where do I download Form 4A?

Form 4A is the prescribed notice for rent increases under RRA 2025 s.6 (amending HA 1988 s.13) from 1 May 2026. Download the live form (PDF) from GOV.UK's assured-tenancy-forms page — it has been available there since 1 May 2026. (Form 4 is now the social-housing form — do not use it for a privately rented property.) To prepare the details you'll transfer into the GOV.UK form, our free Form 4A preparation worksheet gathers parties, rent, dates, and market-rent evidence in one place — no signup. The worksheet is a preparation aid only, not a substitute for the prescribed GOV.UK form.

Q: Is there a Word version of Form 4A?

The government has published Form 4A as a PDF; there is no Word version as of the last review of this page. The official Form 4A wording lives on GOV.UK and only that wording is legally valid — to fill in the GOV.UK PDF you can use a PDF editor. To gather the values you need (parties, rent figures, dates, market-rent evidence) before completing the GOV.UK form, our free Form 4A preparation worksheet lays them out in one Word document. Use the RentersActReady Rent Increase Calculator to compute the earliest valid notice date and earliest effective date (HA 1988 s.13(2)(b)(ii) 52-week test), then transfer those values to the GOV.UK Form 4A.

You'll also typically want a short covering letter to send alongside the Form 4A — for tenant courtesy, to explain the reason for the increase, and to acknowledge the tenant's options under the new s.13 regime. Our Form 4A template download guide covers what to include in the covering letter and has a free Word template (no signup) that pairs with the Form 4A preparation worksheet above.

Q: When must I serve Form 4A?

At least 2 months before the effective date, and no more than once every 12 months. The tenancy must be at least 12 months old. The Rent Increase Calculator works both dates out from the tenancy start or last increase date. For the full rule-set — frequency, amount, notice, and tribunal risk — see Rent Increase Rules under the RRA.

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From 1 May 2026, the only way to increase rent on any assured tenancy in England is the Section 13 process using Form 4A. Informal agreements, rent review clauses, and fixed-term renewal increases all become invalid. If you're a landlord or letting agent, here's exactly how the new process works and what you need to prepare.

What is Form 4A?

Form 4A is the prescribed notice form for a Form 4A rent increase under Section 13 of the Housing Act 1988, as amended by the Renters' Rights Act 2025. "Form 4A" is simply the government's name for the Section 13 notice in the private rented sector from 1 May 2026 — the two terms describe the same document. It replaces Form 4 for privately rented tenancies; Form 4 remains in use for social housing only, and GOV.UK now states on the Form 4 page itself: "Do not use this form if the property is rented privately. You should use form 4A."

Three things make Form 4A different from the old Form 4 it replaces:

• It's the only lawful way to raise the rent. Rent review clauses, CPI/RPI escalators, and informal "shall we say £X from next month?" agreements no longer raise rent on an assured tenancy (HA 1988 s.13(4A), below). Serve Form 4A or the rent doesn't go up.
• Two months' notice, not one. RRA 2025 s.6 sets a flat two-month minimum on the proposed start date for every tenancy — replacing the old one-month-for-monthly-tenancies rule.
• The challenge is now one-way for the tenant. If the tenant refers the figure to the First-tier Tribunal, the tribunal cannot set a rent higher than you proposed (HA 1988 s.14ZB(5)) — but it can confirm, reduce, or defer it.

What's actually on Form 4A

The official Form 4A — "Landlord's notice proposing a new rent for assured tenancies in the private rented sector" — is a 9-page GOV.UK PDF. Most of those pages are the prescribed notes and guidance the government requires the tenant to receive; the part you fill in is shorter than the page count suggests. The information you need to provide is:

• The parties — the tenant's name(s), the landlord's name and the service address, and the agent's details if you use one.
• The property — the address of the let to which the rent increase applies.
• The current rent — what the tenant pays now, and how often (weekly, monthly, etc.).
• The proposed new rent — the figure you want to charge, and from what date it starts.
• The starting (effective) date — the date the new rent takes effect, which must be at least two months after the notice is served and at least 52 weeks after the tenancy began or the last increase.

You do not need to justify the figure on the form itself — Form 4A proposes the rent; the market-rent test only comes into play if the tenant challenges (Step 5). But you should still have your comparable-rent evidence ready before you serve, because a challenge runs on the evidence you can produce, not on the form. The only legally valid wording is the GOV.UK PDF's own wording, so download it fresh each time rather than reusing an old copy or a third-party reproduction.

What changes on 1 May 2026

Rule	Before 1 May 2026	From 1 May 2026
Prescribed form	Form 4	Form 4A
Minimum notice period	1 month (monthly tenancy)	2 months (all tenancies)
Frequency	Once per year for periodic tenancies	Once per year (all tenancies are now periodic)
Rent review clauses	Valid if in the tenancy agreement	Invalid — cannot be used to increase rent
CPI/RPI indexation clauses	Valid if agreed	Void — automatic increases based on any index are prohibited
Informal agreements	Technically possible	Not permitted — only Form 4A counts

The change from 1 month to 2 months' notice is significant. If a tenancy started on 1 May 2026, the earliest you could increase the rent is 1 May 2027 (12-month minimum), and you'd need to serve the Form 4A by 1 March 2027 at the latest (2 months' notice).

The Form 4A process only applies to statutory periodic tenancies — every existing AST converts on 1 May 2026. See AST-to-periodic conversion on 1 May 2026 for the full rules. For the broader phasing (including Phase 2 and 3 expected dates), see when the Renters' Rights Act comes into effect.

The step-by-step Section 13 process under the RRA

Step 1: Check eligibility

Before serving a Form 4A, verify:

• 12-month minimum: At least 52 weeks must have passed since the tenancy began or since the last Section 13 rent increase — whichever is later
• No recent increase: The rent has not been increased by Section 13 in the previous 12 months
• Notice validity: The notice must be in the prescribed Form 4A, correctly served, with the right dates and amounts. A tenant can challenge the notice's validity at the First-tier Tribunal via the new HA 1988 s.13B (inserted by RRA 2025 s.6). Separately, a tenant can refer the proposed rent to the tribunal on market-rent grounds under HA 1988 s.14/s.14ZA
• Compliance gaps do not block a Form 4A at the tribunal — but they bite elsewhere. The Deregulation Act 2015 ss.33–38 "prerequisite" regime (Gas Safety, EICR, deposit protection, Written Statement) applied only to s.21 notices and is in any event repealed by RRA 2025 Sch 2 para 73 (verbatim: "In the Deregulation Act 2015 … omit sections 33 to 41"). The tribunal cannot refuse a Form 4A rent increase on those grounds. Compliance failures still expose you to civil penalties, a deposit-protection penalty of 1–3× the deposit by court order under HA 2004 s.214(4) (the pre-RRA s.21-notice bar at HA 2004 s.215 is moot from 1 May 2026 since Section 21 is abolished by RRA 2025 s.2), and council enforcement — so the readiness check still matters

Step 2: Determine the new rent

The rent you propose must reflect market rent for the property in its current condition. The First-tier Tribunal (FTT) will assess this if the tenant challenges, and they'll compare your proposed rent to similar properties in the same area.

Factors the tribunal considers:

• Comparable rents for similar properties in the locality
• The condition of the property (including any improvements the tenant has made — these are disregarded)
• The terms of the tenancy
• The age, character, and locality of the property

Practical tip: Before proposing a rent increase, check current asking rents for comparable properties on major listing portals. Keep screenshots as evidence in case of a tribunal challenge.

Form 4A sets the process — for the substantive test ("is this actually a fair figure?") see what counts as a fair rent increase under the RRA.

Step 3: Serve Form 4A

Download Form 4A from the GOV.UK assured-tenancy-forms page and complete it with:

• The current rent amount
• The proposed new rent amount
• The date the new rent takes effect (at least 2 months from the date of service)
• Your name and address (or your agent's details)

Serve it on the tenant. Keep a copy and proof of service (recorded delivery, or a signed acknowledgement).

Get the service date right — it's the date that counts, not the date you posted. The 2-month minimum runs from the date the notice is served (deemed received), not the date you put it in the post. If you serve by first-class post, allow for transit: the safe working assumption is that the notice is deemed served two working days after posting unless the tenancy agreement specifies otherwise, so post early and date the effective date generously rather than counting two months from the postmark. In-person delivery or recorded delivery with a signed receipt removes the ambiguity. Whatever method you use, keep dated proof — a tribunal challenge on validity (HA 1988 s.13B) turns on whether the notice was correctly served with the right dates.

Make sure you've given the tenant a service address. Separately from the Form 4A itself, LTA 1987 s.48(1) requires the landlord to have furnished the tenant with an address in England and Wales at which notices can be served — usually satisfied by the tenancy agreement, but the duty is met by any written notice giving the address. If you've never provided one, rent is not lawfully "due" (the s.48(2) consequence) until you do, so confirm it's in place before you serve.

The three most common ways a Form 4A is invalidated: (1) wrong form — using the old Form 4 on a privately rented tenancy (Form 4 is now social-housing only); (2) effective date less than 2 months after service, or less than 52 weeks after the tenancy start or last increase; (3) figures or dates on the notice that don't match what you can evidence. Each is a clean validity ground under s.13B. The Rent Increase Calculator eliminates the date errors; using the live GOV.UK Form 4A eliminates the wrong-form error.

A worked example. Say a tenancy began on 1 June 2026 at £1,200 a month, and you want to move it to £1,300. The earliest the rent can rise is 1 June 2027 — at least 52 weeks after the tenancy start (HA 1988 s.13(2)(b)(ii)). To make 1 June 2027 the effective date, you must serve Form 4A by 1 April 2027 at the latest — two clear months ahead. You complete the GOV.UK PDF showing the current rent (£1,200/month), the proposed rent (£1,300/month), and the effective date (1 June 2027), serve it on the tenant with proof of service, and keep your comparable-rent screenshots on file. If the tenant does nothing before 1 June 2027, the £1,300 simply takes effect. If they apply to the First-tier Tribunal before that date (paying the £47 fee), the tribunal sets an open-market rent that, by HA 1988 s.14ZB(5), can be no higher than your proposed £1,300. The Rent Increase Calculator does the date arithmetic for any start date; the example just shows the shape.

Step 4: Wait for the tenant's response

The tenant has three options:

1. Accept — they do nothing and pay the new rent from the specified date. Silence counts as acceptance: if the effective date passes without a tribunal application, the increase simply takes effect.
2. Negotiate — you can agree a lower amount than proposed (HA 1988 s.13(4)(b), as amended). A genuine agreed figure following a valid Form 4A becomes the new rent without involving the tribunal. (Note s.13(4A) only disapplies escalation clauses — a fresh consensual agreement after a valid notice is expressly preserved.)
3. Challenge at the First-tier Tribunal — the tenant can refer your notice to the FTT, but they must do so before the effective date on the notice (the application is made under HA 1988 s.14(A1)/(A3)). Miss that window and the proposed rent stands.

The timing window is the tenant's, not yours. Once you've served a valid Form 4A you don't need to do anything further — the increase is automatic unless the tenant applies to the tribunal in time. That's why getting the form, the dates, and the figures right at service (Step 3) matters more than anything that happens afterwards: a clean notice that the tenant lets lapse is the most common outcome.

Step 5: If the tenant challenges at tribunal

The FTT determines the market rent for the property. The outcome can be:

• The proposed rent is confirmed — the tenant pays the new amount
• The rent is reduced — if the FTT finds the proposed rent exceeds market rate, they set a lower amount
• The increase is delayed — the FTT can delay the start date by up to 2 months in cases of undue hardship (new HA 1988 s.14ZB(3)(c) + (4), inserted by RRA 2025 s.7)

The tenant's downside to challenging is small — but no longer zero. Since 1 May 2026, applying to the tribunal to challenge a rent increase carries a £47 application fee, set by the First-tier Tribunal (Property Chamber) Fees (Amendment) Order 2026 (SI 2026/485: "On filing an application under section 14(A1) or 14(A3) of the Housing Act 1988 for the determination of rent … £47"). Eligible applicants on a low income or certain benefits can apply for fee remission through the separate Help with Fees scheme (form EX160) — that remission sits in the general court-and-tribunal fee-remission regime, not in SI 2026/485 itself. Beyond that £47, the tenant risks nothing on the rent itself: by new HA 1988 s.14ZB(5) (inserted by RRA 2025 s.7) the new rent the tribunal sets is "(a) the open-market rent, if lower than the proposed rent, and (b) otherwise, the proposed rent" — so the tribunal cannot set a rent higher than the landlord proposed. This is a deliberate change to encourage tenants to challenge — before 1 May 2026 the tribunal could set a higher rent than proposed, which deterred challenges.

What the tribunal process looks like in practice. The tenant must apply before the effective date on the notice — once the increase takes effect unchallenged, it stands. After the application is filed, the FTT typically issues directions (a timetable for both sides to submit evidence), then decides either on the papers or at a short hearing. The single most valuable thing you can do is assemble your market-rent comparables before you serve, not after the tenant applies — the tribunal sets an open-market rent on the evidence in front of it, and a landlord who turns up with three or four genuinely comparable lettings is in a far stronger position than one relying on assertion. Note the new undue-hardship power: even where the tribunal confirms your figure, it can defer the start date by up to two months (HA 1988 s.14ZB(3)(c)+(4)), so build that possibility into your cash-flow planning rather than assuming the new rent starts on the date you put on the notice.

What happens to existing rent review clauses?

Any pre-authorised rent review clause in an existing tenancy agreement — whether it references CPI, RPI, a fixed percentage, or a formula — is of no effect from 1 May 2026. The statutory phrase lives in new HA 1988 s.13(4A) (inserted by RRA 2025 s.6(7)): "any provision of [the tenancy] … is of no effect so far as it provides that the rent for a particular period of the tenancy must or may be greater than the rent for the previous period otherwise than by virtue of a notice, determination or agreement". The clause remains in the agreement text, but it cannot operate to raise the rent.

This means:

• You cannot increase rent based on an agreed formula, even if the tenant signed the clause
• Any rent increase agreed under a rent review clause before 1 May 2026 that takes effect after 1 May 2026 is not permitted (per government transition guidance)
• You must use the Section 13 / Form 4A process (or a s.13(4)(b) agreement that follows a valid s.13 notice, or a s.14 tribunal determination followed by a downward agreement) for all future rent increases

Note — what is preserved. New HA 1988 s.13(4B) (also inserted by RRA 2025 s.6(7)) expressly preserves the parties' general right to vary other terms (including by mutual rent reductions or non-rent-term changes) by agreement. Rent increases by pre-authorised escalation are what is disapplied; consensual variation remains available. Contemporaneous mutual upward variation by genuine agreement is a narrow grey area — take solicitor advice on the specific fact pattern if you are relying on it.

If you have a rent review date coming up between now and 1 May 2026, serve the increase under the current Form 4 before 1 May 2026 to lock it in. If the increase takes effect before 1 May 2026, it stands.

How this affects your cash flow

The new rules create predictable constraints on rental income increases:

• Year 1: No increase possible. You set the asking rent at the tenancy start.
• Year 2 onwards: One increase per year, with 2 months' notice.
• Tribunal risk: Every increase can be challenged, and the tenant's only direct cost in challenging is the £47 application fee (SI 2026/485; fee remission via the separate Help with Fees scheme for those who qualify). Budget for the possibility that increases are delayed by 2-4 months.

If you manage multiple properties, stagger your tenancy start dates so rent reviews don't all cluster in the same month. This smooths your cash flow and spreads your administrative workload.

What to prepare now

1. Set up a rent review calendar. For every tenancy, record: start date, current rent, date of last increase, and earliest date for next increase (start date + 12 months or last increase + 12 months).
2. Gather comparable evidence. Start collecting screenshots of asking rents for similar properties in your area. This is your defence if a tenant challenges at tribunal.
3. Update your processes. Remove any automatic rent review clauses from your standard tenancy agreement templates. Replace with a simple statement that rent will be reviewed in accordance with Section 13 of the Housing Act 1988.
4. Consider your pricing strategy. Since increases are limited to once per year and can be challenged, your initial asking rent matters more than ever. Price accurately at the start — you can't easily correct a below-market rent for 12 months.

For help calculating your next valid rent increase date and notice requirements, try the free Rent Increase Calculator. Looking for where to download the form itself? See Form 4A template download: where to get it.

For the full list of compliance requirements across all Phase 1 areas, see the landlord compliance checklist. For all Phase 1, 2, and 3 deadlines, see the key dates timeline or use the RRA Deadline Tracker.

This guide applies to assured tenancies in England only. It does not constitute legal advice. For specific questions about rent increases or tribunal proceedings, consult a solicitor or the First-tier Tribunal (Property Chamber).

RentersActReady's outputs and action lists are general guidance based on the Renters' Rights Act 2025 and accompanying statutory instruments. Selective-licensing schemes vary by local council — RAR does not encode local licensing conditions, so verify with your local authority (and Propertymark, ARLA, or your governing body) for your specific portfolio. Not legal or professional advice.

Information is current as of the date shown above.