If they do not agree, the tenant must pay rent for the full lease term, even if they move out. A tenant may break the lease for serious problems with the property that make a living there impossible. The tenant should consult with a lawyer before attempting to break the lease and moving early.
There is a rare exception for tenants in the armed services. They can end a lease if they receive a permanent change of station or a deployment order that will last at least 90 days.
Written leases usually do not auto-renew, so the tenant needs to move out by the end of the lease. If a tenant does not move at the end of the lease, the landlord has the right to evict the tenant.
If the landlord continues to accept the usual rent payment every month from the tenant, the landlord and tenant now have a lease that renews monthly. The same lease terms apply.
Tenants in a month-to-month lease who want to move should give at least 30 days written notice before their next rent payment is due. Rent payments due within 30 days of the notice still need to be paid in full, even if the tenant will not live in the apartment for the entire month.