How to Increase Rent Under the Renters' Rights Act (Form 4A)

The new rules on rent increases

The Renters' Rights Act replaced every other way of increasing rent on a private assured tenancy with the statutory section 13 procedure under the Housing Act 1988. The main rules are:

• Rent can only be increased once every 12 months.
• You must serve the prescribed Form 4A, published on GOV.UK.
• You must give at least two months' notice before the new rent starts, up from one month.
• The new rent must start at the beginning of a rental period, such as the normal monthly due date.

Rent review clauses in tenancy agreements, such as fixed annual uplifts or increases linked to inflation, no longer have any effect. An increase agreed informally outside the section 13 process cannot be enforced either. A tenant can agree to pay less than the figure in your notice, but you should not rely on a verbal or emailed agreement to a higher rent.

When you can increase the rent

Plan around the 12-month rule. Once a rent increase takes effect, you cannot bring in another one for at least 12 months. For a new tenancy, the first increase also cannot start until the tenancy has run for at least a year.

Work backwards from the date you want the new rent to begin. That date must be a rent due date, at least two months after you serve the notice, and at least 12 months after the last increase or the start of the tenancy. Allow a few extra days if you serve by post, because the notice period runs from when the tenant receives it.

It is also worth thinking about timing in the wider market. Local rents tend to be strongest when demand peaks, and reviewing the rent at a regular point each year makes it easier for tenants to plan and less likely to come as a shock. A predictable, well-explained annual review is one of the best ways to keep good tenants.

How to fill in and serve Form 4A

Form 4A asks for the details of the tenancy, the current rent, the proposed new rent and the date it will start. Take care with every field, because mistakes can make the notice invalid.

• Use the current version of Form 4A from GOV.UK, not an old copy or a template from before May 2026.
• Name every tenant on a joint tenancy and serve the notice on each of them.
• Show the rent clearly, separating any service charges or bills if they are included.
• Check the start date against the two-month minimum and the rent due date.
• Sign and date it, and include your contact details or your agent's.

Serve the notice in a way your tenancy agreement allows and keep proof: a certificate of posting, a signed receipt or a record of email service if the tenant has agreed to receive notices that way. If a challenge reaches the tribunal, being able to prove service on a clear date avoids an argument about whether the notice was valid at all.

How to set a rent that will stand up to a challenge

The key test is the open market rent: what a similar property in a similar area would let for on the open market today. There is no national percentage cap, but a tenant can challenge any increase they believe is above that level.

Build your figure from evidence rather than instinct:

• Comparable lets: properties of the same type, size and condition within a short distance, ideally ones that have actually let recently rather than only asking prices.
• Condition and features: parking, outdoor space, furnishing and the standard of the kitchen and bathroom all affect market rent.
• Local trends: official figures such as the ONS Price Index of Private Rents show the direction of rents in each area.

Keep this evidence on file and share a summary with your tenant when you serve the notice. Explaining the reason for an increase reduces the chance of a dispute. A local letting agent can provide a free rental valuation based on what similar homes nearby have let for, which is often the strongest evidence you can have.

What happens if your tenant challenges the increase

If your tenant thinks the proposed rent is above the market rate, they can apply to the First-tier Tribunal (Property Chamber) before the new rent is due to start. The service is free for tenants, which is one reason challenges are expected to become more common.

The tribunal looks at evidence from both sides, sometimes including an inspection of the property, and decides what the open market rent is. Two rules work in the tenant's favour:

• The tribunal cannot set the rent higher than the figure in your notice, so asking for more than the market rate brings no upside.
• Where a tenant challenges, the new rent generally starts from the tribunal's decision rather than the date in your notice, and the tribunal can delay it by up to two further months if paying it from that date would cause the tenant undue hardship.

In practice, an overambitious increase can leave you waiting months and then receiving less than a sensible figure would have brought in straight away.

Common mistakes that delay a rent increase

Most failed or delayed rent increases come down to a handful of avoidable errors:

• Relying on a rent review clause. These no longer work. Every increase needs Form 4A.
• Too little notice. One month was the old rule for some tenancies; two months is now the minimum.
• A start date that isn't a rent day. The new rent must begin at the start of a rental period.
• Increasing too soon. Less than 12 months since the last increase makes the notice invalid.
• Missing a joint tenant. Every tenant named on the agreement should be served.
• Asking for well above market rent. It invites a challenge that you are likely to lose.

If you have made one of these mistakes, the usual fix is to serve a fresh, correct notice. The 12-month clock only starts once a valid increase takes effect, so an invalid notice costs time but does not block a new one.

How a letting agent can help with rent reviews

The tighter rules have made agents more useful for rent reviews. A managing agent can value the rent against recent local lets, explain the increase to your tenant, prepare and serve Form 4A correctly, and put together evidence if the tenant goes to tribunal.

Agents also help you balance rent against tenant retention. An empty month or a costly re-let can wipe out the gain from a small increase, and agents who manage hundreds of local homes know what keeps good tenants in place.

The same rules apply to how you set the rent for a new tenancy. You must advertise an asking rent, you cannot invite bids, and you cannot accept offers above the advertised figure. Our Renters' Rights Act guide for landlords covers these advertising rules and the other changes in force since May 2026.

The bottom line

Raising the rent now follows one route: a Form 4A section 13 notice, served at least two months ahead, no more than once a year, at a level you can show is in line with the local market. Landlords who set a realistic figure with good evidence rarely end up at tribunal, and those who serve the form correctly avoid the delays that a mistake can cause. If you would like a local expert to value your rent and handle reviews for you, compare letting agents in your area and get a free rental valuation.

This guide is general information about the law in England as of October 2026 and is not legal advice. Always use the current Form 4A from GOV.UK and check the latest guidance before serving notice.