Of all the changes the Renters' Rights Act made on 1 May 2026, the one most landlords will meet first is the new rule on rent increases. Fixed terms with built-in reviews have gone for most lettings, and with them the familiar ways of agreeing a new rent at renewal. What remains is a single statutory route. It is not complicated, but it rewards preparation.
The rules in brief
For assured periodic tenancies, which is now what most private tenancies in England are, the government's guidance sets out the position plainly:
- The rent can be increased no more than once a year, to the market rate, meaning the rent the property would achieve if it were newly advertised to let.
- The landlord must serve a section 13 notice on Form 4A, giving at least two months' notice before the new rent takes effect.
- Rent review clauses and other routes to an increase are no longer permitted.
- The tenant can challenge the proposed rent at the First-tier Tribunal if they believe it is above the market rate.
- The tribunal cannot set a rent higher than the landlord proposed, and if the tenant challenges, the new rent applies from the date of the tribunal's decision rather than being backdated.
Two related rules sit alongside these. Landlords and agents may not accept offers above the advertised rent or encourage bidding. And rent in advance is limited: nothing may be taken before the tenancy agreement is signed, and no more than one month's rent afterwards.
One exception is worth repeating for prime London. A tenancy where the annual rent exceeds £100,000 cannot be an assured tenancy under the Housing Act 1988, so it sits outside this regime altogether. We wrote about that line on 28 September.
Why the evidence matters more now
Under the old system, a landlord and tenant could agree a new rent at the end of a fixed term, and the market did the rest. Now, if a tenant disputes the figure, an independent tribunal decides what the market rent is. That changes the incentive. An ambitious proposal is no longer simply a starting point for negotiation; if it is challenged, the increase is delayed until the tribunal decides, and the tribunal will not award more than was asked.
The market itself is supportive in many areas. Knight Frank reported this month that prime outer London rents were 3% higher than a year earlier, that new rental listings were down 6.4%, and that there were 8.9 prospective tenants for every new property, a higher ratio than in the post-pandemic period. LonRes recorded average prime London rents 3.8% higher in the year to August. But averages are not your flat. What a tribunal will look at is what comparable homes are actually letting for, in your building, street and condition.
Practical points before you serve a notice
Know your date. The once-a-year rule and the two months' notice mean an increase needs planning, not a decision the week it is due. Keep a record of when and how each notice was served.
Gather the comparables first. Recent lettings of similar homes nearby, with size, condition and furnishing noted, are the strongest support for a proposed figure. Asking rents on portals are weaker evidence than agreed ones.
Be honest about condition. A tribunal assessing market rent will consider the property as it is. If the kitchen is tired or the windows are draughty, the market rent reflects that.
Think about the tenant as well as the figure. A good tenant who stays has real value in a market where a void month can cost more than a year's increase. A proposal that is clearly in line with the evidence is less likely to be challenged and less likely to prompt a departure.
None of this is legal advice, and if you are unsure whether your tenancy is covered, take advice before serving anything.
How we can help
Dolce Vita lets property across the UK from Berkeley Square House in Mayfair. A lettings valuation from us sets out the current market rent for your property with the comparable evidence behind it, which is exactly what you need before deciding on a section 13 proposal. Request a lettings valuation; we acknowledge the same working day and return a written valuation within 24 to 48 hours.
Chris Dawson, Co-Founder
Sources: Ministry of Housing, Communities and Local Government, Renters' Rights Act: an overview for landlords (gov.uk, updated 1 October 2026) and Guide to the Renters' Rights Act (gov.uk, 6 November 2025). Housing Act 1988, Schedule 1. Knight Frank prime London lettings figures, reported October 2026 (Property Industry Eye). LonRes prime London lettings figures for August 2026, 17 September 2026.