How Rent Increases Actually Work Now

Rent review clauses, informal agreements to raise the rent mid-tenancy, contractual annual increases written into old contracts — none of it works anymore. Since 1 May 2026, there's exactly one legal route to increase rent on an existing tenancy, and it's the same for every landlord.

The only mechanism that works

A Section 13 notice, served once every twelve months, giving at least two months' written notice on the correct prescribed form. That's it. Any clause in an old tenancy agreement that tried to allow increases some other way — a fixed annual percentage, a landlord's discretion clause — no longer has legal effect.

What a tenant can actually do about it

A tenant who thinks the proposed rent is above the open market rate can challenge it at the First-tier Tribunal for a £47 fee. The tribunal assesses what the property could reasonably achieve if re-let today, and it cannot set the new rent higher than what the landlord originally proposed — so there's no real downside risk to proposing a fair, defensible figure in the first place.

What this means for how you set the number

• A rent increase now needs to be genuinely defensible against real comparables, not just "what feels reasonable" — a tribunal challenge means someone else will be checking your working.
• Since increases can only happen once a year, there's no room to correct an under-priced rent quietly through several small bumps — it has to be right, once, annually.
• Good written evidence for the figure — comparable lettings, not just instinct — is worth having ready before the notice goes out, not after a challenge lands.

The practical shift

Because every landlord now has exactly one opportunity a year to move the rent, and a genuine chance tenants will test a figure that looks aggressive, getting the number right the first time matters more than it used to. This is where a market-accurate valuation actually earns its keep, rather than being a formality.