We Asked AI to Write a Tenancy Agreement. Here Is What It Got Wrong

We typed a one sentence request into a leading AI chatbot, the same request thousands of landlords type every month: write me a tenancy agreement for my flat in Bristol. It answered in under a minute. Ten numbered clauses, clean legal English, confident as a solicitor. It looked exactly like the real thing.

Then we marked it against the law as it stands in England in August 2026. Six of its ten clauses contained something that is now unlawful or unenforceable. Here is the marking, clause by clause, and what each mistake would actually cost the landlord who signed it.

What the chatbot handed us

The draft called itself an "Assured Shorthold Tenancy Agreement" made under the Housing Act 1988. It granted "a fixed term of 12 months", collected "the first month's rent and the final month's rent" before move in, took "a deposit equal to six weeks' rent", raised the rent each year "by 5% or in line with the Retail Prices Index", banned pets "under any circumstances", and promised the landlord possession through "two months' written notice under Section 21". Tidy, plausible, and wrong from the title down.

The marking

1. There is no such thing as a new AST any more

Assured shorthold tenancies and fixed terms were abolished for England on 1 May 2026. Every residential tenancy of this kind is now a rolling periodic assured tenancy from day one, and a new fixed term cannot be created. The draft's title and its entire 12 month structure describe a tenancy type that can no longer exist. Our guide to the Renters' Rights Act covers the full change.

2. Section 21 is gone

The draft's termination clause leans entirely on Section 21, the old no fault route. Section 21 was abolished on 1 May 2026 and the last transitional cases closed on 31 July 2026. Possession now always requires a legal ground with evidence behind it. A landlord relying on this clause would discover, at the worst possible moment, that their eviction route does not exist. The draft also gives the tenant one month's notice at the end of the term; in reality tenants may leave with two months' notice at any time, ending at the end of a rental period.

3. The rent review clause is dead weight

An annual rise of "5% or RPI, whichever is the higher" reads like sensible planning. Rent review clauses no longer operate. Rent on a periodic tenancy can only rise through a statutory Section 13 notice, once every twelve months, with at least two months' notice, and the tenant can challenge it free of charge at the First-tier Tribunal before it takes effect. A landlord invoicing off this clause would be collecting an increase with no legal basis.

4. Two months of rent up front is now unlawful

First and final month before move in sounds traditional because it was. Since 1 May 2026 a landlord cannot require or accept more than one rental period of rent in advance, and cannot take any rent before the agreement is signed. This clause instructs the landlord to break the law on day one.

5. The deposit is over the legal cap

Six weeks' rent as a deposit has been unlawful for an ordinary flat since the Tenant Fees Act 2019, which capped deposits at five weeks' rent where the annual rent is under £50,000. The chatbot is not even one Act behind the law here. It is two.

6. Blanket pet bans no longer hold

"No pets under any circumstances" is now unenforceable as written. Tenants have a legal right to request a pet, a landlord cannot unreasonably refuse and must normally respond within 28 days. And a detail widely misreported online: the power to require pet insurance was removed from the Act before it passed, so a landlord cannot demand that either.

To be fair, it got a lot right

The repair obligations, deposit protection in a government scheme, the gas safety certificate, quiet enjoyment, 24 hours' notice for inspections: all present and correct. That is precisely what makes a document like this dangerous. It is nine parts competent boilerplate wrapped around an eviction route that no longer exists. A landlord skimming it sees the competent parts. A tribunal sees the rest.

Why the machine fails at this

Not stupidity. Training. These systems learned from a decade of internet tenancy templates, and until 1 May 2026 the internet's standard template was exactly what it produced. English tenancy law then changed more in one day than in the previous thirty years, and a chatbot's knowledge often ends before that day. It answers from the old world with total confidence. To catch its mistakes you need to know the current law yourself, and if you know the current law, you did not need the chatbot. That is the trap. It is also why we keep a clear line between the jobs AI does well and the jobs it must not do in our own business.

What to use instead

Use an agreement written for the law as it is now. Our assured periodic tenancy agreement is free in the resources library, built for the Renters' Rights Act, and kept current, alongside the rest of our landlord templates. Pair it with our plain English guide to the Act. And if you would rather never think about tenancy paperwork again, our Bristol property management service exists for exactly that.

This article is general information, not legal advice. It describes the law in England as at 11 August 2026. The AI excerpts are quoted from a draft generated on 11 August 2026 from the one sentence prompt above.