How to Serve a Section 13 Rent Increase and File Proof of Service

The form is filled and the PDF left your outbox — that is not yet a served Section 13 file. Confirm the let is assured periodic and 52 weeks have cleared, complete current Form 4A with every named tenant and a period-day start, serve by a method the agreement allows, diary deemed service so the two-month clock is real, keep form + proof + short market notes in one increase tab, and update the rent schedule when the new rent starts.

Thursday. Rowan has one let in Luton. The tenancy rolls monthly from the 5th. She downloads Form 4A, puts £1,100 → £1,175 and a start date of 5 July, and emails the PDF to the repairs address. The notices clause only lists first-class post and leaving at the property. She never gets a certificate of posting. She marks “served 24 June — increase 5 July”. That is less than two months and the wrong method.

Emailing Form 4A is only valid if the tenancy agreement allows email service. GOV.UK’s landlord rent-increases guide and the form’s own note say the same: if methods are not agreed, hand the notice over, leave it at the tenant’s address, or send by registered post — and keep evidence. A Sent-folder PDF to a repairs inbox is not the increase tab. Typical mistake: marking “served” the day you hit send. The risk is a clock and a method that will not stand if the tenant challenges service.

Disclaimer: IziRento is operations software, not legal advice. Local tenancy rules vary; check a qualified adviser for binding decisions.

Is your let assured periodic — and have 52 weeks passed?

Before you fill anything, confirm the tenancy is a privately rented assured periodic let in England and that at least 52 weeks have passed since the tenancy began (first increase) or since the last increase took effect. From 1 May 2026 the private-sector route is Form 4A under section 13 — social-rented Form 4 is the wrong sheet for a private let.

Do check the GOV.UK assured tenancy forms index for current Form 4A. GOV.UK: increase only once a year, not in the first year, and follow section 13 every time — even if the figure is already agreed. If a Form 4 notice went out before 1 May 2026, use the transitional rules on that page; do not invent a fresh clock from memory. Do not treat a rent-review clause as a shortcut after 1 May 2026 for a private assured periodic rise. Wales, Scotland and Northern Ireland differ — this file is England.

What must Form 4A include before you serve?

Download the current Form 4A PDF and complete it: every named tenant, the current rent, the proposed rent, and a start date at the beginning of a tenancy period that clears both the two-month notice and the 52-week rules. Do not invent a freehand letter that skips the prescribed form after 1 May 2026.

Do use the live Form 4A PDF. Notes on that form: serve at least two months before the new rent can start; first increase not until 52 weeks after the tenancy began; further increases generally 52 weeks after the previous one, with a 53-week anniversary-drift rule; start at the beginning of a period — monthly from the 5th means an increase on the 5th. Shelter England (1 May 2026): wrong notice period or start date can invalidate the notice. Do put every named tenant on the form; do not treat “lead tenant” as everyone on a joint tenancy.

How do you serve Form 4A and diary deemed service?

Open the notices clause before you choose a channel. Serve in person, by post, or by email only if the written agreement allows email. If the agreement is silent, Form 4A’s landlord note points to handing the notice over, leaving it at the tenant’s address, or sending by registered post — and evidencing service.

Do write three dates on one line: the day you posted or handed the form, the day you treat as deemed service, and the Form 4A start date. Count two months from deemed service to the earliest lawful start on a period day. The notices clause lives in the tenancy agreement folder. In practice, if email was never agreed for statutory notices, re-serve by an allowed method and reset the clock. Keep the posting certificate, tracked receipt, signed hand receipt, or sent-item with the PDF — a memory of hitting send is not proof.

What to keep in the increase tab with the notice?

One labelled folder on this let: the completed Form 4A PDF, proof of service, and a short dated market note of three to five local comparables (source, date, type, asking or achieved if known). Label the tab with the proposed start date. When the tenant says “I never got it”, you open a folder, not a shrug.

Do save the market note before you serve. Asking-price screenshots alone are weaker than achieved lettings if referred; see GOV.UK open-market rent determination (10 August 2026). Do not draft tribunal pleadings here, and do not reopen the advertised-rent bidding file. The safety-certificate service log is a neighbour habit for dated proof; this tab is Form 4A, not CP12.

When to update the rent schedule after the increase?

On the effective start date in Form 4A, update the rent schedule for that period so due versus paid stays honest. Do not leave the old figure on the schedule because the bank already shows the new amount.

Do open the rent schedule by period and change the period row on the start date. If the tenant refers the notice to the tribunal before that date, file the referral in the same increase tab and do not treat yourself as entitled to the new rent until that process says so. Application clocks live on GOV.UK — this article stops at the keep-file.

Success bar: eligibility and period day checked; Form 4A completed with every named tenant; allowed method used; deemed-service day written; form + proof + short market notes in one tab; rent schedule updated on the start date. Verify that checklist. Workflow: eligibility → Form 4A → allowed method + deemed-service diary → increase tab → B01 update. An IziRento workspace can hold the Form 4A PDF, proof path and market note on that lease.