How to serve a Section 13 rent increase, step by step

Since 1 May 2026, a Section 13 notice on the prescribed Form 4A has been the only lawful way to increase the rent on an assured periodic tenancy in England. This guide walks a landlord through the whole process – deciding the figure, filling in the current form, getting the dates right, serving it properly and keeping the proof that protects you if the increase is challenged.

Step 1: Decide the figure

Start with the rent itself, because everything else follows from it. The Renters’ Rights Act did not cap rent increases, but it changed the balance of risk: a tenant can refer any proposed rent to the First-tier Tribunal, and the tribunal decides the open market rent for the property. Under the new rules it cannot set the rent higher than the figure you proposed, so an ambitious number no longer carries the upside it once might have – it simply invites a challenge and delays the increase.

The practical approach is to set a figure you can defend with genuine local comparables: similar properties, in similar condition, let recently in the same area. Keep a note of those comparables. If the increase is ever referred to the tribunal, that evidence is what supports your proposed rent.

Step 2: Use the current Form 4A

The rent increase must be served on the prescribed form – Form 4A – and it must be the current version. Only Form 4A is valid for a Section 13 increase on an assured periodic tenancy, and a homemade version or an out-of-date template is invalid even if it contains exactly the same information. Old Form 4 templates built around one month’s notice are a particular trap, because the Act doubled the minimum notice to two months.

Step 3: Get the three dates right

The effective date – the date the new rent starts – is where most notices fail. Three separate rules control it, and the notice must satisfy all of them at once:

• Two months’ notice. The tenant must have at least two months between receiving the notice and the new rent taking effect.
• The rent period rule. The new rent must take effect on the first day of a rent period – the day rent is contractually due. Two months added to the service date rarely lands on a due date, so it usually rolls forward to the next one.
• The 12-month gap. The rent can only go up once a year: at least 52 weeks after the last increase took effect, or 12 months after the tenancy began if it has never been increased.

Working these three rules together by hand is easy to get wrong, and being even one day too early voids the whole notice. Our Section 13 date calculator applies all three rules to your dates and shows the working, so you can put the right effective date on the form with confidence. The 12-month rule explained covers the once-a-year gap in more depth.

Step 4: Serve the notice

“Serving” the notice means getting it to the tenant. How you do that matters, because the two-month clock runs from when the tenant is treated as having received it, not from when you posted or wrote it.

• By hand. Delivering it in person, or through the letterbox, is the most certain method. Note the date and, ideally, have a witness or take a dated photograph.
• By post. First-class post is treated as delivered about two working days after posting – this is “deemed service”. Check what your tenancy agreement says about service, and always allow for the delay when you set the effective date.
• By email. Only serve by email if the tenancy agreement permits service that way, or the tenant has agreed to it. If in doubt, use a physical method as well.

Step 5: Keep proof of service and records

If the tenant simply pays the new rent from the effective date, the increase is done. But you should assume every notice might be questioned, and keep the evidence that shows you did it correctly:

• A dated copy of the completed Form 4A exactly as served.
• Evidence of how and when it was served – proof of posting, a delivery photograph, or a note of hand delivery with any witness.
• The local comparables you relied on to set the figure.

Good records cost nothing and settle most disputes before they start. They are also exactly what you would rely on if the rent is referred to the tribunal.

What happens next

Once served correctly, the tenant has three options: accept the new rent and pay it from the effective date, negotiate informally with you, or refer the proposed rent to the First-tier Tribunal before the effective date. If it is referred, the tribunal decides the open market rent and cannot set it above your proposed figure. You can read how that process works in our guide on how tenants challenge a rent increase at the First-tier Tribunal. If you want to be sure your notice is watertight before it goes out, check it against what makes a Section 13 notice invalid.

Frequently asked questions

Disclaimer: TenancyTools.uk provides general guidance and calculation tools, not legal advice. The Section 13 rules described on this page apply to assured periodic tenancies in England under the Housing Act 1988 as amended by the Renters’ Rights Act 2025. Different rules apply in Wales, Scotland and Northern Ireland. While we work hard to keep every page accurate and up to date, you should verify dates and requirements against the current prescribed form and guidance on GOV.UK before serving or responding to a notice, and take professional advice where the outcome matters.