Liability Regimes in a Property Lease Contract
If two individuals are listed as tenants in a lease property contract in Spain, it should be borne in mind that both are bound by the lessor. If one of the tenants decided to leave the apartment and the other one to stay in the apartment, it'd advisable to notify the landlord.
It is also important to distinguish the liability regime that has been agreed in the contract, that is, if a joint (“solidaria”) or several (“mancomunada”) liability was contractually established. Thus, if a joint liability regime was agreed, any of the tenants would be liable for the debts to the landlord in the event of non-payment of rent by one of the parties.
On the contrary, in the case of several liable co-tenants, each of the co-tenants responds only for the proportional part that corresponds to the agreed rent, so the landlord may only claim said proportional amount and not the total to one of the tenants .
This matter is not expressly regulated in the Spanish Law for Urban Leases (LAU), therefore, referring to the Spanish Civil Code, the general rule is the several liability between the parties, unless agreed especifically the joint character in the contract (article 1137 CC). Thus, in case of abandonment of the property by one of the tenants, whatever the reason, it would be faced with a subjective modification of the contract that should require the consent of the landlord.
Therefore, the creation of a new contract would not be required, but it’d be advisable to collect in an annex to the original contract the variations arised.