If you are on a joint tenancy, just one tenant can end the tenancy by giving notice. If everyone else wants to stay, government guidance says that your landlord can create and sign a new tenancy agreement, or alternatively additional tenants can be added to an existing tenancy agreement.

You’re all responsible for paying the rent on the whole property so you’re also all responsible for finding a new housemate. 

When you have found someone to move in, your landlord will want to put your new housemate on to the tenancy agreement. This is one of the few things they can still charge a fee for. They can charge a flat £50 to change a name on a contract (or make other changes to it) – they can charge more but only if they can prove their costs.

It is also possible for the landlord to refuse to add replacement tenants to the tenancy. They have always been able to do this – previously they could refuse to renew the tenancy after the fixed term ended.

You may be able to negotiate with your landlord on the fee or whether to amend the tenancy; the alternative for the landlord would be for everyone to move out, meaning they’d need to find a new set of tenants with the extra costs that would entail.