Mid-Tenancy Variations: Adding Tenants, Rent Changes, Addendums
← Part of Tenant ManagementMid-Tenancy Variations: Adding Tenants, Rent Changes, Addendums
RRA 2025 Update
What changed under the Renters’ Rights Act 2025
Section 21 abolished. Fixed-term assured tenancies abolished. Ground 8 threshold raised to 3 months. Information Sheet required for every tenancy by 31 May 2026. Read the full guide.
Tenancies change over time — tenants come and go from shared houses, rents need adjustment, tenancy terms need updating. Before the Renters’ Rights Act 2025, much of this happened at fixed-term renewals; from 1 May 2026, with fixed terms abolished, mid-tenancy variations are the principal way tenancies adapt. The Act has also tightened the rules around specific changes — rent increases must use Form 4 with two months’ notice and only once every 52 weeks, and tenant additions or removals require careful documentation to preserve the tenancy’s legal continuity. This page covers rent variations under the new framework, adding/removing/substituting tenants (deeds of variation, the practical options), term variations (pets, business use, utilities), property changes during the tenancy, and the deed-vs-simple-variation question.
Why mid-tenancy changes are different post-RRA 2025
Tenancies change over time. Tenants come and go from shared houses; rents need adjustment as market conditions shift; tenancy terms need updating where circumstances change. Before the Renters’ Rights Act 2025, the typical approach was to let mid-tenancy issues run to the end of the fixed term, then renegotiate as part of a renewal. Where that wasn’t possible — a mid-term change of tenants, a structural issue with the agreement — landlords used variation deeds or addendums to make targeted changes without resetting the whole tenancy.
The post-1-May-2026 framework has changed this picture substantially. Fixed terms no longer exist for new assured tenancies; every tenancy is periodic from day one. There is no natural “renewal” point where wholesale renegotiation happens. Mid-tenancy variations have therefore become the principal way that tenancies adapt to changing circumstances. The procedural and legal framework around them matters more than it did before.
At the same time, the Act has tightened the rules around specific kinds of variation — rent increases must use Form 4 with two months’ notice and only once every 52 weeks, and the addition or removal of named tenants requires careful handling to preserve the tenancy’s legal continuity. This page covers the main types of mid-tenancy variation, how to document each properly, and the common pitfalls.
Categories of mid-tenancy variation
Mid-tenancy changes typically fall into one of several categories:
Rent variations — adjusting the rent during the tenancy. Now governed by the strict Form 4 / section 13 framework under the RRA 2025. Cannot be done by simple agreement: the prescribed form and notice period must be used.
Tenant changes — adding a new tenant (e.g. a new partner moving in), removing a tenant (e.g. one tenant leaving a houseshare), or substituting one tenant for another. Requires a deed of variation or new tenancy agreement involving all parties.
Term changes — adjusting the tenancy’s terms (e.g. permitting a pet that was previously prohibited, allowing minor business use, varying repair allocations). Requires a written variation signed by both parties.
Property changes — significant alterations to the property (e.g. converting an attic, adding a structure) that affect the let. Often requires variation of the description of premises in the agreement.
Letting party changes — change in the landlord (e.g. property sold to a new owner) or in the agent acting for the landlord. Generally handled by notification rather than formal variation, but the tenant’s position needs to be considered.
Rent variations: the Form 4 / section 13 framework
Under the post-RRA 2025 regime, rent increases must follow the Form 4 / section 13 procedure. The substantive requirements:
- Minimum two months’ notice from the date of service to the date the new rent takes effect. (Increased from one month under the pre-RRA rule.)
- Maximum once per 52 weeks. A landlord cannot increase rent more often than once a year, calculated from the previous Form 4.
- Form 4 prescribed form must be used. A simple letter or informal agreement does not work — the prescribed form is required for the increase to take effect.
- The new rent takes effect at the start of a rental period — so for a monthly tenancy, on the start date of one of the monthly periods, not part-way through.
- Tenant has the right to refer to the First-tier Tribunal before the new rent takes effect. Importantly, the Tribunal cannot now set a rent higher than the landlord proposed (an RRA 2025 reform that capped the previous risk to tenants of challenging).
Mutual rent reductions (where the parties agree the rent should go down — for example, where the tenant has accepted lower-quality accommodation or where market conditions favour the tenant) do not need Form 4. They can be handled by simple agreement in writing. The Form 4 procedure exists to protect tenants from unilateral landlord increases, not to constrain agreed reductions.
See our Form 4 guide for the detailed procedure.
Adding or removing tenants
Changes to the named tenants on a tenancy are among the most common mid-tenancy variations. They are also among the most legally consequential, because the identity of the tenants determines who is liable on the tenancy and to whom the landlord owes obligations.
Adding a tenant (new partner, family member moving in)
When the existing tenant wants to add another person to the tenancy — for example, a new partner moves in — the legal options:
1. Allow occupation but not add to the agreement. The new person occupies the property as a permitted occupier under the existing tenant’s licence. They have no direct legal relationship with the landlord. The existing tenant remains solely liable for rent and obligations. This is the simplest route and is appropriate where the new occupier is a partner, family member, or close friend whose occupation is essentially derivative of the existing tenant’s.
2. Add the person to the tenancy. Both names go on the agreement and both become liable jointly and severally. This requires either a deed of variation amending the existing agreement, or a fresh tenancy agreement signed by both. Generally requires referencing the new person, providing them with the prescribed Information Sheet, deposit handling for any additional deposit, and updating the deposit protection scheme registration. More work, but creates a cleaner legal position.
Choice between the two depends on the situation. Where the relationship is intended to be long-term and the new occupier is paying rent or sharing financial responsibility, adding to the agreement makes sense. Where the new occupier is a transient guest or a supplementary occupier, leaving the agreement unchanged is simpler.
Removing a tenant (one tenant leaving a houseshare)
When one tenant wants to leave a joint tenancy mid-term, the legal effect depends on whether the tenancy is continued. The principal options:
1. The departing tenant simply leaves and the remaining tenants continue. The legal tenancy continues with all original tenants still named. The departing tenant remains liable jointly for rent and obligations (until the tenancy is varied or ended). The remaining tenants take responsibility for the property in practice. This is messy: the departing tenant remains technically liable, the deposit is still held against all tenants, and the landlord’s position is unclear.
2. Deed of variation removing the departing tenant. Cleaner. A formal document signed by all parties (departing tenant, remaining tenants, landlord) which:
- Releases the departing tenant from future liability (subject to any unpaid sums up to the date of release).
- Confirms the remaining tenants continue on the same terms.
- Addresses the deposit — typically retaining the existing deposit against the continuing tenants, with any return to the departing tenant handled by agreement among the tenants directly.
- Updates the deposit protection scheme registration to reflect the new occupier list.
3. Surrender and re-grant. The existing tenancy is surrendered (ended by mutual agreement) and a fresh tenancy is granted to the remaining tenants. Cleaner from a documentation perspective but produces a new tenancy with all the consequences — a fresh deposit protection clock, a fresh Information Sheet, possibly different terms reflecting current circumstances.
In houseshares with a sequence of departures and arrivals, the deed-of-variation route becomes administratively heavy. Many landlords with high-turnover student or professional houseshare portfolios use a structured “tenancy swap” process — a single template variation handles each individual change.
Substituting one tenant for another
Substitution combines removal and addition. Documentation:
- Reference the incoming tenant.
- Right-to-rent check on the incoming tenant.
- Deed of variation signed by all parties: removes the departing tenant, adds the incoming tenant, confirms the remaining tenants continue.
- Adjust deposit protection registration.
- Provide the Information Sheet to the incoming tenant.
Most professional landlords handle this routinely and have template documentation. A professionally drafted deed of variation costs £150-£400 typically; bespoke handling for unusual cases more.
Term variations
Variations to the substantive terms of the tenancy — permitting a pet, allowing minor business use, varying who pays for council tax, adjusting the inventory — should be documented in writing and signed by both parties. The principles:
Use a written variation. Email exchange creates a valid variation in most cases, but a single signed document is cleaner and harder to dispute. Specify the existing clause being varied and the new terms.
Date the variation. The variation takes effect from the specified date. Backdating is generally to be avoided (creates evidential issues if disputed later).
Don’t vary core protections. Statutory implied terms (the section 11 repairing covenant, the homes-fit-for-human-habitation duty, the deposit protection regime) cannot be varied or excluded. A clause attempting to do so is unenforceable.
Consider whether the variation requires consideration. A variation that benefits one party at the expense of the other (e.g. tenant agrees to take on additional repairs) may need consideration to be enforceable. A deed (signed under seal) dispenses with the need for consideration. A simple written agreement works where there is mutual exchange of benefits.
Common term variations and how to handle them
Permitting a pet. The RRA 2025 introduced a tenant right to request a pet, with the landlord required to consent unless reasonable grounds for refusal exist. Where the landlord consents, document the consent, identify the specific pet (species, breed, name), specify any insurance requirements, and address the deposit (where allowed under the Tenant Fees Act 2019 deposit cap) or any other adjustments. See our pets-allowed tenancy guide for the substantive framework.
Permitting business use. Where a tenant wants to run a small business from the property (typically a service business with limited foot traffic), the landlord can vary the agreement to permit it. Considerations: insurance (the landlord’s buildings insurance may need notification; the tenant should have appropriate business contents and liability cover), planning (substantial business use can trigger change-of-use issues), and potential rates liability. For most “incidental” business uses (working from home, occasional client meetings), no formal variation is needed — the tenancy already permits ordinary residential use including reasonable home working.
Varying utility responsibilities. Where the tenancy initially specified that the landlord paid utilities (sometimes the case for student lets or shared accommodation) but circumstances change — perhaps because consumption has been substantially higher than expected — the parties can agree a variation. Address the timing (from when does the variation apply), the amount or method of calculation, and any catch-up adjustment for past periods.
Updating the inventory. Where significant changes to furnished items have occurred (the landlord has replaced furniture, the tenant has acquired permitted personal items, items have been removed), the inventory should be updated by addendum signed by both parties. Photographs of the new state are valuable. The updated inventory becomes the reference point for future deposit deductions.
Property changes during the tenancy
Where the property itself changes during the tenancy — typically because the landlord wants to carry out works such as a loft conversion, extension, or major renovation — the tenant’s rights and the landlord’s obligations need careful handling.
Minor improvement works
Replacing a boiler, redecorating, or carrying out compliance-driven work (gas safety remediation, electrical upgrades) usually fits within the section 11 implied repairing framework or is permitted under the standard tenancy access provisions. The tenant must allow access for such work but is entitled to reasonable notice and management of the inconvenience. The tenancy agreement is unaffected.
Substantial works
Major works — extensions, structural alterations, prolonged contractor presence — affect the tenant’s use of the property and may require formal handling. Options:
Agreement to suspend the tenancy. The parties can agree to suspend rent or vary the tenancy terms during the period of works. Common where the works prevent normal occupation.
Re-grant after works. Where works are extensive enough that re-grant makes sense, surrender the existing tenancy and grant a fresh tenancy reflecting the new property configuration. Used particularly where the works change the character of the property significantly.
Possession and re-let. Where works require vacant possession (e.g. major restructuring), the landlord may need to recover possession and re-let after works. Under the RRA 2025, this requires a Section 8 ground — likely Ground 6 (works requiring vacant possession), which is mandatory if the conditions are met. Notice period 4 months. See our Section 8 guide.
Documentation: deeds vs simple variations
A persistent question is whether a variation needs to be by deed (signed under seal, witnessed) or whether a simple written agreement suffices.
Simple written variation is sufficient where:
- The variation is supported by mutual consideration (each party gives something).
- No interest in land is being created or transferred.
- The original tenancy was not by deed (most assured tenancies are not by deed).
Deed is required or strongly recommended where:
- No consideration supports the variation (e.g. the landlord releases the tenant from an obligation without receiving anything in return). A deed dispenses with the need for consideration.
- The original tenancy was by deed (rare for assured tenancies).
- The variation involves the assignment of an interest or the release of a guarantor — these often need to be by deed.
- Best practice: any substantive variation involving release of a tenant from joint and several liability should be by deed.
In commercial practice, many landlords use deeds for all substantive variations as a matter of caution. The marginal cost is small and the legal certainty is greater.