What to check in your tenancy agreement before challenging a rent increase

Before you challenge a rent increase, spend ten minutes on your tenancy agreement. Five things it might say will change your strategy — and with the Renters' Rights Act 2025 kicking in on 1 May 2026, what's on that paper matters more than ever.

You don't need a law degree. You just need to know where to look.

Why your tenancy agreement matters

Your agreement is the starting point. It sets:

• The starting rent (the one the landlord is now trying to raise).
• The tenancy type (which decides the legal route the landlord must follow).
• The review route (whether there's a rent review clause, and what it permits).
• The notice period (what the contract says, and how it interacts with statutory rules).
• Your wider rights (some agreements are more generous than the law requires).

Sometimes the contract strengthens your position. Occasionally it complicates it. Either way, get the full picture before you put anything in writing to your landlord.

The 5 clauses to look for

1. The tenancy type

Find the part that says what kind of tenancy this is — usually near the top. You're looking for one of:

• Assured shorthold tenancy (AST) — the most common private rental in England.
• Assured tenancy — less common for new lets, more common for older and housing association agreements.
• Contractual / common law tenancy — usually where rent is very high, the landlord lives in the property, or it's a company let.

The tenancy type decides the legal route. Section 13 applies to assured and assured shorthold tenancies. If yours is something else, the rules are different.

What changes on 1 May 2026: under the Renters' Rights Act 2025, all existing ASTs in England convert to periodic assured tenancies. Fixed terms for ASTs end.

2. The rent review clause

This is the big one. Search the document for "rent", "review", "increase", or "adjustment". Clauses usually come in three shapes:

• Index-linked — rent rises in line with a named index (CPI, RPI, CPIH) on a stated date.
• Market rent — landlord can review rent to "market rate" after a set period.
• Fixed uplift — rent goes up by a set percentage (e.g. 3%) on a set date.

Check three things: when it kicks in, how the new rent is calculated, and what notice the landlord has to give.

What changes on 1 May 2026: from that date, contractual rent review clauses in assured tenancies become unenforceable. The only valid route to raise rent will be Section 13 (served on Form 4A, with the statutory notice period). If a landlord invoked a clause correctly before 1 May, that's a different question — we covered it in our earlier post on Section 13 vs contractual rent review clauses.

3. The notice period

Look for a clause that says how much notice the landlord must give to change the rent. It's often buried in the rent review clause, or in a general "notices" clause near the end.

Compare that to the statutory notice period for Section 13 — a minimum of one month for weekly, fortnightly, or monthly rents (longer for quarterly, half-yearly, or yearly).

If your contract gives you more notice than the statute — say, three months instead of one — the longer period is a term that benefits you. If the landlord serves less, you can challenge on that ground alone. A contract more generous than the law is genuinely on your side.

4. The term — fixed or periodic

Check the term of the tenancy:

• Fixed term (e.g. "12 months from 1 September 2025") — you're locked in for that period, and the landlord usually can't raise rent within it unless the contract allows it.
• Periodic tenancy ("rolling", or "continuing month-to-month after the fixed term ends") — the tenancy rolls on until one side gives notice.

During a fixed term, the landlord's only route to raise rent is usually a rent review clause — they can't just serve Section 13. On a periodic tenancy, Section 13 is the main statutory route.

After 1 May 2026, fixed-term ASTs end and all assured tenancies become periodic. So this distinction matters most right now, in the transition window. If your landlord is trying to raise rent mid-fixed-term without a valid rent review clause, that's a procedural ground to challenge on.

5. Any clause restricting rent increases

Rarer, but worth a look. A small number of agreements include clauses that:

• Cap the rent at a fixed figure for the duration of the tenancy.
• Limit increases to a specific percentage per year.
• Commit the landlord to a named rent for a stated period (sometimes seen in build-to-rent or corporate lets).

If you find one of these and it's more favourable than the default Section 13 route, it still applies. The statutory rules set a floor, not a ceiling, on your rights. If you're unsure how to read it, Shelter or Citizens Advice can help.

What the Renters' Rights Act 2025 changes from 1 May 2026

Quick recap, because the timing matters. From 1 May 2026:

• All assured shorthold tenancies in England convert to periodic assured tenancies.
• Fixed terms for ASTs end.
• Contractual rent review clauses become unenforceable for assured tenancies.
• Section 13 (with Form 4A) becomes the only valid route for a landlord to raise rent.
• The minimum notice period for Section 13 is two months.
• Tenants keep the right to challenge at the First-tier Tribunal.

So "what does my tenancy agreement say about rent?" goes from being important to being the question. The agreement still sets the starting rent, the tenancy type, and any more-generous terms you've negotiated — but it can't override or short-circuit Section 13.

If your landlord uses a contractual clause after 1 May 2026

If a landlord serves a rent increase on or after 1 May 2026 that relies on a contractual rent review clause — rather than a Section 13 notice on Form 4A — the increase isn't valid.

No need to panic. Just respond politely but firmly in writing. Something like:

Thank you for your notice dated [date]. Under the Renters' Rights Act 2025, contractual rent review clauses are no longer enforceable for assured tenancies in England. To increase the rent, you would need to serve a valid Section 13 notice using Form 4A, with the statutory notice period. I'll continue paying the existing rent of £X per month until a valid notice is served.

Keep a copy. Keep it calm. You're not accusing anyone — just setting out the position.

What if your agreement is more generous than Section 13?

Sometimes a tenancy agreement gives you more than the statute: longer notice periods, capped increases, a named rent for a stated period, restrictions on how often rent can be reviewed.

These terms still apply after 1 May 2026. The Renters' Rights Act 2025 changes the statutory route for rent increases, but it doesn't strip out contractual terms that benefit the tenant. A contract can be more generous than the law — it just can't be less.

If your landlord serves Section 13 in a way that conflicts with a more-generous contractual term, you have grounds to challenge.

How this fits into a challenge

A strong challenge usually combines two grounds:

1. Procedural grounds — did the landlord follow the correct process? (Right notice period, right form, right service, correct tenancy type, right use of rent review clause vs Section 13.)
2. Market rent grounds — is the proposed rent actually in line with comparable properties in the area?

Your tenancy agreement is where procedural grounds start. Then you layer on market evidence to argue that even if the process is correct, the figure itself is too high.

Procedural ground + market rent ground = strongest case. Always has been.

Next, have a read of our full checklist of grounds to challenge a Section 13 rent increase and our guide to how to read a rent increase notice.

5 key takeaways

• Before you challenge, spend ten minutes reading your tenancy agreement. Five clauses change your strategy.
• Check the tenancy type, rent review clause, notice period, term, and any clauses restricting rent increases.
• From 1 May 2026, contractual rent review clauses become unenforceable for assured tenancies — Section 13 with Form 4A becomes the only valid route.
• Terms in your agreement that are more generous than the statute still apply. A contract can be kinder than the law, just not harsher.
• The strongest challenges combine procedural grounds (did the landlord follow the rules?) with market rent grounds (is the figure actually fair?).

FAQs

Does my tenancy agreement override Section 13?

No. Section 13 is the statutory route for rent increases on assured and assured shorthold tenancies. Your agreement can be more generous than Section 13 — longer notice periods, for example — but it can't take away statutory protections. From 1 May 2026, contractual rent review clauses for assured tenancies become unenforceable, and Section 13 becomes the only valid route.

What if I can't find a rent review clause in my agreement?

Not unusual — plenty of agreements don't include one. If there's no rent review clause, the landlord can't increase the rent during a fixed term. On a periodic tenancy, they'd need to serve a valid Section 13 notice with the statutory notice period.

My agreement mentions CPI — what is that?

CPI stands for Consumer Prices Index — a measure of inflation published monthly by the Office for National Statistics. Some rent review clauses link annual increases to CPI. Check the exact wording: some use CPI, some use RPI (Retail Prices Index), some use CPIH (a variant that includes housing costs). The differences affect how much the rent can legally rise.

Can my landlord change the tenancy agreement to remove protections?

No. Once you've signed, the terms apply. A landlord can't unilaterally change the agreement — if they want new terms, they'd need to offer a new tenancy, and you'd have the choice of whether to accept. From 1 May 2026, the Renters' Rights Act 2025 also adds statutory protections that can't be contracted away.

What if my tenancy agreement was signed years ago — is it still valid?

Yes. A tenancy agreement is a binding contract for the tenancy it covers. The Renters' Rights Act 2025 converts existing ASTs to periodic assured tenancies from 1 May 2026 — the agreement itself doesn't change, but the tenancy type it sits under does. The clauses still bind both sides, unless they conflict with the new law.

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RentSOS helps private renters in England check whether a Section 13 rent increase is fair and, where there are grounds, build the case to challenge it. We're not a law firm and nothing here is legal advice. For individual guidance, speak to Shelter, Citizens Advice, or a housing solicitor.