The only way to end a tenancy before the fixed term expires is if:
there's a break clause that lets you give notice early (break clause)
the landlord agrees you can leave (surrendering the tenancy)
the tenant/landlord finds a replacement tenant (under mutual agreement)
Check the tenancy agreement to see if it has a break clause. A break clause allows the landlord or tenant to end the tenancy before the end of the fixed term.
The tenancy agreement will tell you:
when the break clause applies (for example, 6 months after the tenancy starts)
how much notice each party has to give
whether notice must be given in writing
To ensure that the notice is valid, it should either be hand delivered or sent by recorded post. You may also want to provide a copy of the notice via email, if the tenancy agreement states that delivery by email is acceptable.
Surrendering your tenancy
If there is no break clause in the agreement, then you can only end the tenancy if both parties agree to it. This is called surrendering the tenancy.
The parties can only surrender the tenancy if the landlord agrees. The landlord should confirm this in writing - this will help prove when the tenancy ended. It will also help avoid misunderstandings and problems later.
Surrender occurs when both parties to a tenancy, the landlord and tenant, voluntarily agree to bring the tenancy to an end. Once surrender has taken place, all obligations and rights under a tenancy also come to an end.
There are two types of surrender - express surrender and implied surrender. For more information, read Surrendering a tenancy.
Finding a replacement tenant
This process is similar to surrendering a tenancy, in that the landlord will need to agree to the replacement. The tenant should ask the landlord whether they agree to a replacement tenant before the tenant starts searching.