The National Residential Landlords Association has warned landlords to gather stronger evidence for rent rises after Hamptons data showed 166 market-rent tribunal decisions in July – the highest monthly total on record.
The warning sharpens a trend already visible since the Renters’ Rights Act took effect on 1 May. Under the new system, tenants have more time to challenge section 13 increases, unsuccessful appeals are not backdated, and tribunals cannot set a rent above the figure proposed by the landlord.
That changes the balance of risk for landlords now because more tenants can challenge with little downside, while owners who rely on portal listings or broad local assumptions may struggle to prove that a proposed increase matches the true market level.
Record tribunal volumes follow the new section 13 rules
NRLA said Hamptons recorded 166 market-rent decisions in July, around four times the level seen in the same month last year. It also said 73 percent of tribunal decisions made by August related to applications submitted on or after 1 May, showing how quickly the post-Act system is feeding into formal disputes.
This follows Landlord Knowledge’s recent report on rent tribunals rising after the Renters’ Rights Act rule change and its coverage of a new rent-rise challenge tool for tenants. The latest NRLA warning adds a practical point that many landlords will need immediately: evidence quality may decide whether a rise holds up.
According to NRLA, the wait between application and decision has also started to fall, from around five to six months earlier in the year to about three months by August, after extra judicial capacity was added.
Achieved rents matter more than asking rents
One of the clearest messages in the warning is that recently achieved rents are more persuasive than advertised rents from portals. That matters for self-managing landlords in particular because asking prices can look strong online while agreed deals on similar homes tell a softer story on the ground.
NRLA also said property condition is affecting outcomes. Around a quarter of recent decisions reduced what would otherwise have been local market rent because the home was not considered up to standard, with factors ranging from EPC ratings to worn interiors and ageing white goods.
The result is a tighter test for landlords who have deferred upgrades while still trying to move rents up. In practice, rent-setting, evidence collection and maintenance standards are now more closely tied together.
What this means for landlords
- If you’re planning a rent rise this autumn: collect evidence of recently agreed local rents, not just portal screenshots.
- Watch for: tribunal scrutiny of condition issues that can drag down the level considered market-justified.
- Bottom line: a section 13 notice is now safer when it is backed by clean comparables and a property in good order.
Editor’s view
The old habit of nudging rents up and seeing if a tenant accepts looks harder to sustain under the new regime. Landlords who want higher rents will need to think more like case-builders and less like hopeful price testers.
Author: Editorial Team – UK landlord & buy-to-let news, policy, and finance
Published: 3 September 2026
Sources: National Residential Landlords Association, Hamptons
Related reading: Hamptons says rent tribunals rose after RRA rule change
📘 Renters’ Rights Act: Complete Landlord Guide
Everything you need to know about the new rules – 1 May 2026
