How to increase rent legally: the Section 13 notice
Rent increases used to be handled several ways: a clause in the agreement, a new fixed term at a higher figure, or a conversation followed by a standing order amendment. The Renters’ Rights Act closed most of that off. With every tenancy periodic from the outset and rent-review clauses no longer doing the work they did, the statutory route is the route.
That route is a Section 13 notice, and it is a prescribed form with rules that are easy to satisfy and easy to fail.
The rules, in order
Once
One increase per twelve months
Measured from the last increase, or from the start of the tenancy if there has not been one
Form
The prescribed form
Not a letter, not an email restating the figure. The statutory form, completed correctly
Notice
The minimum notice period
Given before the new rent takes effect — check the current period, it was extended under the Act
Effect
It begins on a period start date
The new rent takes effect from the beginning of a rental period, not mid-month
Every one of those is a validity condition. A notice giving a day less than the minimum, or specifying a start date mid-period, is not a slightly-late notice. It is not a notice.
The most expensive mistake is the quiet one
The tenant can challenge it
A tenant who thinks the proposed rent is above market can apply to the First-tier Tribunal before the increase takes effect. The tribunal determines the open market rent for the property.
Two things about that are worth internalising. First, the tribunal can only determine a rent at or below what you proposed under the Act’s reforms — so an application no longer risks the tenant ending up worse off, which means more of them will apply. Second, “market rent” means evidenced market rent. If you are proposing an increase you cannot support with comparable lettings, you are proposing a figure the tribunal will reduce.
What a defensible increase looks like
01
Check eligibility
Twelve months since the last increase or the tenancy start
02
Evidence the figure
Comparable local lettings, dated and kept — not a percentage uplift
03
Serve the prescribed form
Correct notice period, effective from a period start date
04
Retain proof of service
What was sent, to whom, how and when. This is the part disputes turn on
Where increases actually fail
The tenancy is not eligible yet. An increase served ten months after the last one is invalid regardless of how reasonable the figure is.
The effective date is wrong. Rent periods are rarely calendar months. A tenancy that began on the 18th has periods running 18th to 17th, and an increase specified from the 1st does not align.
Service cannot be proved. The notice was correct and nobody can show it arrived. In a contested case the burden is on the landlord, and “it was posted” is weaker than most people assume.
The old rent keeps being charged. A valid increase followed by an unamended standing order produces an arrears figure that is technically correct and operationally toxic — chasers going out on a difference the tenant does not know exists.
Doing this at portfolio scale
One increase is an afternoon. Two hundred, each with its own anniversary date and its own rental period, is a system problem — and it is the kind of system problem that produces silent invalidity rather than an obvious failure.
Tekniti refuses an increase that is not yet eligible and tells you the next date it would be, computes the effective date from the tenancy’s actual rent periods rather than the calendar, generates the prescribed form, and keeps proof of service on the audit trail against the tenancy. The refusals are the useful part: an increase the software declines to serve is an increase that would have been unwound later.
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