What makes a section 21 notice invalid

When a landlord serves a valid section 21 notice on an assured shorthold tenant, the court must make a possession order. If the notice was not valid, the tenant has a defence to possession proceedings.

A section 21 notice can be invalid if the landlord:

• served the notice on a private tenant on or after 1 May 2026

• did not start possession proceedings within the time limit

• did not serve the notice correctly

• did not follow the tenancy deposit rules

• failed to provide an energy performance certificate (EPC) or gas safety certificate

• failed to provide the How to Rent guide

• does not have a licence for the property where required, or has not applied for a licence

• took a banned fee by charging a prohibited payment or retaining a holding deposit

• served the notice after the tenant complained about the condition of the property (retaliatory eviction)

Some of the above requirements only apply to private landlords.

Find out more about the section 21 possession process on Shelter Legal.

A landlord can serve a section 21 notice to end an assured shorthold tenancy without providing a reason or ground for possession.

Notices before 1 May 2026

A private landlord can use a section 21 notice served before 1 May 2026 to evict a tenant.

If the landlord applied to court for a possession order before 1 May 2026, the section 21 notice remains valid until proceedings are concluded.[1]

If the landlord did not apply to court before 1 May 2026, they must apply by 31 July 2026 at the latest. If the landlord does not apply to court in time, the section 21 notice is no longer valid and the tenant becomes an assured tenant.[2]

If the notice is invalid, the tenancy becomes an assured tenancy on 1 May 2026.[3]

Find out more about the section 21 possession process.

When the tenancy remains assured shorthold

Most assured shorthold tenancies in the private rented sector became assured tenancies automatically on 1 May 2026.[4] A landlord cannot serve a section 21 notice on an assured tenant.

A private tenancy remains an assured shorthold tenancy where before 1 May 2026, the landlord has served either:[5]

• a valid section 21 notice

• a valid section 8 notice

The landlord can continue possession claims on a valid section 21 or section 8 notice.

While the tenancy remains an assured shorthold tenancy, a section 21 notice could be served on the tenant after 1 May.[6]

The landlord must begin possession proceedings by 31 July 2026 at the latest. If the landlord begins possession proceedings by 31 July, the tenancy remains an assured shorthold tenancy until possession proceedings are concluded.[7]

Section 21 in the social rented sector

A social landlord, such as a housing association, can serve a section 21 notice to end an assured shorthold tenancy in social housing after 1 May 2026. Section 21 will be abolished for social tenancies in 2027.

Most social tenants do not have assured shorthold tenancies. Social tenants who have assured shorthold tenancies include housing association starter tenants.

Find out more about housing association tenancies.

The section 21 notice is invalid if the landlord has not served the notice correctly.

A notice might be invalid if the landlord:

• did not use the correct form

• did not give the right amount of notice

• served the notice on a private tenant on or after 1 May 2026

Find out more about service of a section 21 notice.

Most assured shorthold tenancies in the private rented sector became assured tenancies automatically on 1 May 2026.[8] A landlord cannot serve a section 21 notice on an assured tenant.

A tenancy remains an assured shorthold tenancy where before 1 May 2026, the landlord has served either:[9]

• a valid section 21 notice

• a valid section 8 notice

The landlord can continue possession claims on a valid section 21 or section 8 notice.

If the notice is not valid or ceases to be valid, the tenant becomes an assured tenant.[10]

If a private landlord applied to court before 1 May 2026, the notice remains valid until possession proceedings are concluded.[11]

If a private landlord has not applied to court before 1 May 2026, they must start possession proceedings within a time limit. The time limit depends on when the notice was served, but the landlord must have started possession proceedings by 31 July 2026 at the latest.[12]

Find out more about the section 21 possession process.

Table: Section 21 time limits

When the notice period is longer than two months

If the required section 21 notice period was longer than two months, the landlord must start possession proceedings:[13]

• within four months of when the notice expires

• by 31 July 2026 at the latest

For example, if the tenancy period is three months, the landlord must start possession proceedings within four months of the date the notice expires, or 31 July 2026 if this date comes first.

What the landlord must do before the deadline

The landlord must request that the court issue a claim form to start possession proceedings before the time limit ends. [14]

If the landlord requests the court issue a claim form before the time limit, the notice remains valid until possession proceedings are concluded.[15] The tenant remains an assured shorthold tenant until the possession process ends.

If the landlord does not start possession proceedings in time

If the landlord does not start possession proceedings in time:

• the section 21 notice is no longer valid

• the tenant becomes an assured tenant

• the landlord must serve a section 8 notice if they wish to obtain possession

Find out more about assured tenancies.

A landlord cannot serve a valid section 21 notice where the tenant paid a deposit and either the:[16]

• deposit was not protected within the relevant time limits, usually within 30 days

• deposit is not currently protected with an authorised scheme

• tenant (and any relevant person) has not been given all the prescribed information

• deposit is something other than money

A relevant person is anyone who pays the deposit on behalf of the tenant.

The tenant or relevant person can apply to the County Court for compensation if the landlord has not complied with the rules.

Failure to protect the deposit

A notice is invalid if the landlord did not protect the deposit in an authorised scheme within 30 days from receiving the deposit.[17]

A notice is invalid if the deposit is not protected with an authorised scheme when the section 21 notice is served.[18]

Tenants can contact the scheme administrators to check if their deposit is protected.

The landlord can serve a new valid notice if either:[19]

• the deposit is returned to the tenant or relevant person in full, or subject to any deductions agreed with the tenant

• the tenant and any relevant person made a claim for compensation for the failure to protect the deposit, and the claim has been determined by the court, withdrawn, or settled out of court between the landlord and tenant

Where a landlord must return the deposit to serve a valid notice, it is arguable that the deposit is not returned until the tenant or relevant person actually receives it, so any notice served before then would be invalid.[20]

Where a deposit was paid for a fixed term tenancy that became a statutory periodic tenancy before 6 April 2007 (and has not been renewed since) the section 21 notice can be valid if the landlord protected the deposit at any time before service.[21]

Failure to provide prescribed information

A notice is invalid if the landlord has protected the deposit within the relevant time limit but has not given the tenant and any relevant person the prescribed information.[22]

The landlord can serve a new valid notice after:[23]

• the landlord has given the tenant or any relevant person the prescribed information

• the deposit has been returned to the tenant or any relevant person in full, or subject to any deductions agreed with the tenant

• the tenant or any relevant person made a claim for compensation for the failure to protect the deposit, and the claim has been determined by the court, or withdrawn, or settled out of court between the landlord and tenant

It is uncertain whether the requirement for prescribed information applies when the tenancy began before 6 April 2007.

Renewal of tenancies

If the tenancy is replaced by a new tenancy (a statutory periodic tenancy or a new fixed term) while the deposit was protected in an authorised scheme, the deposit protection rules are met for the new tenancy if the:[24]

• landlord and tenant are the same

• premises are the same or substantially the same

• deposit was protected during the previous tenancy

• prescribed information was given during the previous tenancy

• deposit is with the same scheme as when the prescribed information was given

This includes if there has been a further fixed term or periodic tenancy between the original and current tenancy.

If the conditions are met, the deposit protection requirements are deemed to have been fulfilled in relation to the new tenancy. This applies even if the deposit was protected, or the prescribed information was served, outside of the required time limits in the original tenancy.

As a result, the landlord is able to serve a valid section 21 notice to end the subsequent tenancy.

Change of landlord

Where there is a change of landlord during the tenancy, the new landlord might need to take action to ensure they comply with the tenancy deposit rules.

The County Court decided that a section 21 notice was invalid where the new landlord did not provide the tenant with an updated version of the prescribed information despite having the previous landlord's account with the tenancy deposit protection scheme transferred to them.[25]

A landlord cannot serve a valid section 21 notice where they have failed to provide the tenant with a copy of both:[26]

• the gas safety certificate from before the tenant moved into the property

• the current gas safety certificate

This requirement only applies to ASTs granted or renewed on or after 1 October 2015.[27]

The landlord should provide the tenant with a copy of the gas safety certificate before they move in.[28]

When a gas safety check was carried out but the certificate was provided late

The Court of Appeal held that where a landlord carries out a gas safety check but fails to provide the tenant with a copy of the certificate before the tenant moves in, the landlord can remedy it by providing that certificate later.[29]

Where no gas safety certificate is provided

The Court of Appeal held that the absence of a gas safety certificate for the gas safety check carried out before the tenancy started meant the landlord could not serve a valid section 21 notice.[30]

Procedural requirements

In a County Court case, the court held the landlord failed to comply with the requirements when the gas safety certificate was not signed by the engineer.[31]

A tenancy agreement might contain a clause that sets out when documents are deemed to have been served on the tenant. If the landlord complies with the tenancy agreement, a gas safety certificate can be deemed to be validly served even if the tenant claims not to have received it.[32]

Under gas safety regulations, the landlord must provide the gas safety certificate within 28 days of a gas safety check. Failure to provide the gas safety certificate within 28 days of the check does not affect the validity of a section 21 notice.[33]

A landlord cannot serve a valid section 21 notice where they have failed to provide the tenant with a copy of an energy performance certificate (EPC).[34]

This requirement only applies to ASTs granted or renewed on or after 1 October 2015.[35]

The landlord can provide the EPC at any time before service of the notice, or at the time the notice is served.[36] The EPC must be valid when the landlord provides it.[37] The regulations do not specify that the EPC must still be valid at the point when the notice is served.

The County Court held that a landlord who rented out individual en-suite rooms in a house in multiple occupation (HMO) was not required to provide an EPC certificate for each room.[38] It is uncertain whether an EPC must be given for the whole building.[39]

A section 21 notice is invalid if a private landlord fails to provide a tenant with a copy of the government's How to Rent guide.

The How to Rent guide can be provided at any time before the service of the section 21 notice or at the time the notice is served.[40]

This requirement only applies to ASTs granted or renewed on or after 1 October 2015.[41] It does not apply where the landlord is a private registered provider of social housing.[42]

A paper copy of the guide must be provided unless the tenant has notified the landlord or agent that they accept service of notices and other documents by email.[43]

Which version the landlord must provide

The landlord must provide the current version of the guide at the time it is given. Find the current How to Rent guide at gov.uk: How to rent: the checklist for renting in England.

Nearly Legal has a version checker.

A landlord is not required to provide another copy of the guide to a tenant each time it is updated. If the tenancy is renewed with the same tenants (including where the tenancy becomes statutory periodic at the end of a fixed term), the landlord only needs to provide the guide if it has been updated in the meantime, in which case the new version must be provided.[44]

A property may need to be licenced if it is a house in multiple occupation (HMO) or in an area where selective licencing applies.

A landlord cannot serve a valid section 21 notice if they require a licence for the property but do not have one. They can only serve a valid section 21 notice once they have the licence or if they can show they have applied for one.[45]

A landlord of a flat in an unlicensed house in multiple occupation (HMO) cannot serve a valid notice for as long as the HMO remains unlicensed.

A landlord can apply for a licence or a temporary exemption notice on the basis that they are planning to take steps to ensure that the property will no longer require licensing. A section 21 notice is valid if the application has not been withdrawn and the authority has either:[46]

• not reached a decision on the application

• decided not to grant the application, but either an appeal has been made against the decision, or the appeal period has not yet ended

A notice is invalid if the landlord has taken a banned fee or unlawfully retained a holding deposit, unless the money is either:[47]

• repaid before the notice is served

• credited towards the tenant's rent or tenancy deposit

A landlord cannot charge a tenancy fee unless it is expressly permitted, such as rent or a tenancy deposit.

The person who made the payment has to give their consent for the money to be credited towards the tenant's rent or tenancy deposit.

The ban applies to charges for tenancies that started after 1 June 2019. This includes tenancies renewed after this date, for example with a new fixed term. For agreements that started before 1 June 2019, the ban applies to charges made on or after 1 June 2020.

Find out more about banned tenant fees.

A retaliatory eviction is when a landlord serves a section 21 notice after a tenant complains about poor conditions and the local authority serves a relevant notice.

A relevant notice is either an:[48]

• improvement notice in relation to a category 1 or 2 hazard

• emergency remedial action notice

A notice is not valid if either of the following two scenarios apply.

Scenario 1: section 21 after service of relevant notice

A landlord cannot serve a section 21 notice during the six month period beginning on the day:[49]

• of service of a relevant notice by the local authority

• on which suspension of the relevant notice ended

Scenario 2: section 21 after tenant's complaint to landlord

A landlord cannot serve a section 21 notice where all the following steps apply.[50]

1. Before service of the section 21 notice, the tenant made a complaint to the landlord or the landlord's agent in writing about the condition of the property, including the common parts.

2. The landlord failed to respond in writing within 14 days giving a reasonable timetable for taking action, or issued a section 21 notice in response

3. The tenant made a follow-up complaint to the local authority about the same, or substantially the same, issue.

4. The landlord issued a section 21 notice to the tenant, if not already given in response to the initial complaint.

5. As a result of the tenant's complaint, the local authority served a relevant notice on the landlord.

Steps 1 and 2 are not required when the tenant does not know the landlord's postal or email address and has made reasonable efforts to contact the landlord.[51]

A section 21 notice served after the tenant's initial complaint to the landlord can be valid where the relevant local authority notice is suspended.[52]

The court must strike out any proceedings for possession if a section 21 notice was valid when served but has become invalid by the possession hearing because the local authority has served a relevant notice.[53]

An order for possession made following a section 21 notice cannot be set aside if a relevant local authority notice was served after the order for possession was made.[54]

Common parts

If the complaint and relevant notice concern the common parts, the section 21 notice is invalid if the:[55]

• landlord has a controlling interest over the common parts

• conditions of the common parts affect the tenant's enjoyment of their tenancy or of the common parts that the tenant is entitled to use

Common parts include communal areas such as stairwells and corridors.

Exemptions to retaliatory eviction

Protection from retaliatory eviction might not apply where the relevant notice and the section 21 notice were served before October 2018.[56]

A section 21 notice can be valid if the local authority's notice was served in error, quashed, or reversed, or while the relevant notice is suspended.[57]

A tenant would not have protection from retaliatory eviction if the:[58]

• condition complained of is a result of the tenant's behaviour

• property has been repossessed by the landlord's lender (or a receiver who has been appointed by the lender to act on behalf of the landlord), the mortgage predates the tenancy, and the lender intends to sell the property with vacant possession

• landlord is a private registered provider of social housing

• section 21 notice is given in relation to a property that is genuinely on the market.

This does not apply where the landlord wants to sell the property to an associated person, including family members, business partners, or employees[59]