Published 3 March 2025 | By FJP Investment Editorial Team

Last updated: September 2026

For a straightforward agreed change to a tenancy agreement in England, a written amendment, variation or addendum can record the revised term without replacing the whole contract. Identify the original agreement, set out the exact change, state its effective date and obtain the agreement of the relevant parties. Keep a copy alongside the original tenancy.

Changing the tenants or increasing rent can require a different process. This guide explains how to change a tenancy agreement in England, when an addendum is appropriate and how England’s 2026 rental reforms affect the steps involved.

Important: This article relates primarily to private assured tenancies in England. Different rules apply in Wales, Scotland and Northern Ireland, and specialist advice may be needed for unusual or disputed situations.

Can a tenancy agreement be changed?

Yes. A tenancy agreement can be changed, but how the change should be made depends on what is being altered and why.

For many contractual changes, the landlord and tenant can agree a variation and record it in writing. This may be done by:

• signing a written variation to the existing tenancy agreement;
• adding an addendum containing the new or amended term; or
• in some circumstances, ending the existing arrangement by agreement and entering into a new tenancy agreement.

However, not every change to a tenancy arises because the landlord and tenant have renegotiated the contract.

Tenancy law can itself change the legal position. That is exactly what happened on 1 May 2026, when major reforms altered the way assured tenancies operate in England.

How do you amend an existing tenancy agreement?

For a straightforward contractual change, the safest practical approach is usually to record precisely what is changing in writing.

The document should make clear:

• which tenancy agreement is being amended;
• the names of the parties;
• the property address;
• which existing term is being changed;
• the wording of the replacement or additional term;
• the date the change takes effect; and
• the agreement of the relevant parties.

Keeping the amendment with the original tenancy agreement also makes it easier for both sides to understand the complete set of terms later.

The greater the significance of the change, the more sensible it becomes to obtain professional advice rather than relying on informal wording.

What is a tenancy agreement addendum?

A tenancy agreement addendum is an additional document that sits alongside the original tenancy agreement.

Rather than replacing the entire contract, it records a new condition or modifies a particular existing provision.

For example, a landlord and tenant might use an addendum to record agreed permission for a particular alteration to the property or another change to the way the tenancy operates.

The addendum should identify the original agreement clearly and state that, except for the changes contained in the addendum, the remaining terms continue to apply.

What is a variation of a tenancy agreement?

A variation of tenancy agreement means changing one or more terms of the existing contract.

The expression is often used interchangeably with amendment, although legally the precise effect will depend on what has been agreed.

A written variation can be particularly useful where only a relatively small number of terms need changing and there is no reason to replace the entire document.

In most cases, clarity is more important than the title given to the document. Both landlord and tenant should be able to understand exactly what has changed and when.

What changed for tenancy agreements on 1 May 2026?

The Renters’ Rights Act introduced some of the most significant changes to the private rented sector in England for many years.

Most existing assured shorthold tenancies automatically became assured periodic tenancies on 1 May 2026. New assured tenancies granted after that date also operate on a rolling basis rather than having a fixed end date.

This means that a private assured tenancy may run weekly or monthly and continue until it is properly ended.

If an older tenancy agreement contained a fixed end date, that date generally ceased to have effect when the tenancy converted under the new rules.

Importantly, landlords were not required to issue an entirely new tenancy agreement simply because of the legal transition.

Where there was already a written agreement, landlords or their agents were generally required to provide tenants with the government’s Renters’ Rights Act Information Sheet instead.

You can read the current government guidance in the Renters’ Rights Act overview for landlords.

This is an important distinction when discussing amendments in 2026: a tenancy does not necessarily need rewriting simply because the law affecting it has changed.

What is a tenancy agreement?

A tenancy agreement records the terms of the relationship between landlord and tenant.

It will normally deal with matters such as:

• the identity of the landlord and tenant;
• the property being rented;
• the amount of rent and when it is payable;
• the rental period;
• responsibilities for repairs and maintenance;
• deposit arrangements;
• permitted use of the property;
• rules relating to occupants, pets or alterations; and
• how notices between the parties may be given.

A tenancy agreement can be written or, in some situations, oral. However, written terms provide considerably more certainty if there is later disagreement about what was agreed.

For landlords considering rental property more generally, our guide to things to know before investing in buy-to-let property covers some of the wider responsibilities involved.

Why might a tenancy agreement need to be changed?

There are numerous reasons why a landlord or tenant may want to amend an existing arrangement.

Common examples include:

• adding another person to the tenancy;
• removing or replacing an existing joint tenant;
• changing responsibility for particular bills;
• adding agreed conditions concerning use of the property;
• recording permission for a pet;
• correcting inaccurate information;
• changing contact details or notice provisions;
• allowing an alteration that was previously prohibited; or
• recording another change that both parties have agreed.

Some matters that used to be dealt with through contractual clauses now have specific statutory procedures. Rent increases are a particularly important example.

Adding a tenant to an existing tenancy agreement

One of the most common reasons for changing a tenancy agreement is to add another tenant.

This might happen when a partner moves into the property or when the household composition changes.

Current government guidance on joint tenancies confirms that additional tenants can be added to an existing tenancy agreement.

Before doing so, the landlord may need to carry out the same checks that would normally apply when accepting a new tenant and should make sure the documentation accurately records the new arrangement.

Once somebody becomes a joint tenant, the legal implications can be significant. Joint tenants will normally share responsibility for obligations such as payment of rent.

Adding somebody to a tenancy should therefore be distinguished from simply allowing an additional occupier to live at the property.

Removing or replacing a tenant

Removing somebody from a joint tenancy can be more complicated than adding them.

Under the current assured periodic tenancy system, one joint tenant will usually be able to give notice that ends the joint tenancy.

If some occupants want to remain in the property afterwards, the landlord and remaining tenants may need to agree a new tenancy arrangement.

In other situations, the parties may agree to alter the composition of the tenancy without everybody moving out.

Because the consequences can affect rent liability, deposits and the continuation of the tenancy itself, this is an area where the parties should avoid simply crossing a name off the original agreement.

Can the rent be changed by amending the tenancy agreement?

This is one of the areas where the 2026 rules matter most.

For assured periodic tenancies in England, landlords now generally need to use the statutory section 13 process when increasing rent.

Landlords must use Form 4A – Landlord’s notice proposing a new rent and give the tenant at least two months’ notice before the proposed new rent takes effect.

Rent can generally be increased only once a year, and not during the first year of the tenancy.

Importantly, government guidance states that the section 13 procedure must be followed each time the rent is increased, even if the tenant has agreed to the proposed increase.

This means landlords should not assume that simply signing an addendum containing a higher rent is enough.

A tenant who believes the proposed rent is above the open market rent may be able to ask the First-tier Tribunal to determine the appropriate amount.

Current guidance is available in the government’s guide to rent increases for assured periodic tenancies.

Legal considerations when changing a tenancy agreement

A tenancy agreement cannot override statutory rights simply because a landlord and tenant have written something into the contract.

Any proposed change should therefore be considered alongside current housing law.

This has become particularly important since the 2026 reforms, because some wording contained in older tenancy agreements may no longer reflect the law even though the physical document itself has not been rewritten.

For example, an old assured shorthold tenancy may still contain a fixed end date on paper, but that does not necessarily mean the date continues to have legal effect.

Does every tenancy change require the tenant’s agreement?

No. It is important to distinguish between a landlord attempting to change the contractual terms and a change that occurs because legislation provides a particular mechanism.

If a landlord simply wants to rewrite a contractual obligation, they will generally need the tenant to agree to that change.

However, there are statutory procedures that operate independently of ordinary contract variations. The section 13 rent-increase process is one example.

Likewise, changes introduced directly by legislation can affect the tenancy regardless of whether the original agreement has been physically amended.

That is why landlords should be cautious about relying on an old tenancy template without checking whether the terms are still consistent with current law.

Can a landlord charge for changing a tenancy agreement?

Sometimes, but there are restrictions.

Where a tenant requests a change to the tenancy agreement — for example, asking for a person to be added or removed — a landlord or agent can generally charge up to £50 for the work involved.

If the genuine reasonable cost is higher than £50, a higher amount may be charged, but evidence should be provided to justify it.

The landlord does not have to charge a fee at all.

The important point is that landlords and letting agents cannot simply invent large administration charges for routine tenancy changes.

More information can be found in the government’s guidance on fees that can be charged as part of a tenancy.

Can a tenancy agreement be changed to allow a pet?

Yes, but the position for pets also changed significantly in England on 1 May 2026.

A tenant or prospective tenant can now request permission to keep a pet, and a landlord cannot unreasonably refuse the request.

If permission is given, it can be sensible to record the arrangement clearly so that both sides understand what has been agreed.

However, the right to request permission exists under the legislation itself, so an old blanket “no pets” clause should not simply be treated as the end of the matter.

Each request needs to be considered on its individual circumstances.

Pet-friendly rental accommodation has also become increasingly important to tenants, something we have previously considered in our article on what tenants are willing to pay more for.

Do you need a completely new tenancy agreement?

Not necessarily.

If the parties are making one relatively straightforward amendment, a written addendum or variation may be clearer and easier than replacing the whole agreement.

A new agreement may make more sense where the identity of the tenants has changed substantially or where so many provisions need altering that maintaining multiple amendments would become confusing.

However, landlords should be particularly careful about using older tenancy agreement templates after the 2026 reforms.

New assured tenancies in England cannot simply be created as traditional six or 12-month fixed-term ASTs in the way many landlords were accustomed to before May 2026.

If a landlord uses a document that purports to impose a fixed end date on an assured periodic tenancy, that end date will not operate in the traditional way.

For this reason, replacing a tenancy agreement should not simply involve downloading an old template and changing the names.

What information should be recorded when a tenancy changes?

Where a written amendment is appropriate, it is sensible to create a clear record.

That might include:

• the date of the original tenancy agreement;
• the full property address;
• the landlord’s details;
• the tenant or tenants affected;
• the original wording being amended, where relevant;
• the new wording;
• the effective date;
• any consequential changes to other terms; and
• signatures or another clear written record of agreement.

Copies should be retained by the relevant parties.

What about the tenancy deposit when tenants change?

Adding, removing or replacing tenants may also affect the tenancy deposit arrangements.

A landlord should check how the deposit is currently protected and whether the deposit protection scheme requires the tenant details or prescribed information to be updated.

This should not be overlooked simply because the occupants have agreed between themselves who is leaving or joining.

Our landlord’s guide to tenancy deposit schemes provides further background on deposit protection.

Can a landlord change the tenancy because their costs have increased?

Higher mortgage costs, insurance premiums, repairs or other expenses do not automatically give a landlord the right to rewrite the tenancy agreement.

If the proposed change concerns rent, the statutory rent-increase procedure should be followed where it applies.

If the landlord wants to alter another contractual obligation, the landlord will generally need to consider whether the existing agreement allows it and whether the tenant’s agreement is required.

The fact that a landlord’s own costs have increased does not by itself allow the landlord to remove rights the tenant already has.

Can a tenant ask for a tenancy agreement to be changed?

Yes.

A tenant is free to approach the landlord or letting agent and propose an amendment.

Common requests include adding a partner, changing the names on the tenancy, seeking permission for a pet, changing a particular contractual restriction or agreeing an earlier end to the tenancy.

The landlord does not automatically have to agree to every contractual variation requested by a tenant, although particular statutory rights — such as the right to request a pet — may affect how the request must be considered.

Does this guidance apply throughout the UK?

No.

This article focuses on England.

Housing law is devolved, meaning the legal frameworks applying in Wales, Scotland and Northern Ireland are different.

For example, Wales uses occupation contracts under the Renting Homes (Wales) Act framework, while Scotland and Northern Ireland have their own private-rental rules.

Anyone changing a tenancy outside England should therefore use guidance specific to the jurisdiction where the property is located.

Frequently asked questions about changing a tenancy agreement

How do you amend an existing tenancy agreement?

Where a contractual change is agreed, it can often be documented through a written variation or addendum identifying the original agreement, the exact change and the date it takes effect. More substantial changes may justify a new agreement.

What is an addendum to a tenancy agreement?

An addendum is a supplementary document that sits alongside the original tenancy agreement and records one or more additional or amended terms.

Can a landlord change a tenancy agreement without permission?

A landlord cannot normally just rewrite agreed contractual terms unilaterally. However, statutory processes and changes in the law can affect the tenancy without an ordinary contractual variation. Rent increases under the current section 13 regime are an important example.

Can you add somebody to an existing tenancy?

Yes. Additional tenants can be added to an existing assured periodic tenancy with the appropriate agreement and documentation. Becoming a joint tenant carries legal responsibilities, including responsibility for rent.

Can one tenant be removed from a joint tenancy?

Potentially, but this should be handled carefully. Depending on the circumstances, the existing tenancy may need to end and a new agreement may be created for the occupants who remain.

Can a landlord charge for adding or removing a tenant?

Where the tenant requests the change, a landlord or agent may generally charge up to £50 for the work involved. A higher charge should only reflect reasonable higher costs that can be evidenced.

Can you change the rent by signing a tenancy addendum?

For assured periodic tenancies in England, landlords generally need to follow the statutory section 13 process using Form 4A. Government guidance states that this process must be followed even where the parties have agreed the increase.

Do old AST agreements need to be rewritten after the 2026 changes?

Not simply because of the reforms. Most existing ASTs automatically became assured periodic tenancies on 1 May 2026. Where a written agreement already existed, the legislation did not generally require the landlord to issue a replacement agreement solely because of that conversion.

Final thoughts

Changing a tenancy agreement can be straightforward when the proposed amendment is simple and everybody understands what has been agreed.

However, landlords and tenants should remember that the tenancy agreement does not operate in isolation from housing law.

That is particularly important in 2026.

The Renters’ Rights reforms fundamentally changed private assured tenancies in England, including the move away from fixed-term ASTs, new procedures for rent increases and strengthened rights around matters such as keeping pets.

For relatively minor contractual changes, a clear written variation or addendum may be sufficient. Where tenants are joining or leaving, rent is changing, or the proposed amendment could affect important legal rights, greater care is needed.

Above all, avoid relying blindly on an old tenancy template.

Record changes clearly, use the correct statutory procedures where required, and obtain professional legal advice where there is uncertainty or disagreement.

This article is provided for general information only and should not be regarded as legal advice.