Which law governs a commercial lease? Is whatever is signed valid?

Question

José Manuel Alburquerque · Accepted Answer

The “Ley de Arrendamientos Urbanos” (LAU), Spain's urban tenancies act, which is national law and also applies in Catalonia. But in a commercial lease, what is agreed is what mainly counts. The law imposes only a few rules and fills in what the lease does not say. That is why almost anything that is signed is valid, including clauses that would be void in a tenancy of a flat. Clauses that go against those few mandatory rules, such as the rules on the statutory deposit (“fianza”), are not valid, nor are those that go against the law in general. The order of the rules First, the rules that the law imposes on all tenancies, whether residential or not. These are mainly the rules on the deposit, other guarantees and the form of the contract. Next, whatever has been agreed. If the lease says nothing, the rules the law lays down for non-residential tenancies. They deal with repairs and works, sale of the premises, assignment and subletting, the tenant's death, goodwill compensation and the grounds for terminating the lease. Lastly, the Spanish Civil Code (“Código civil”), for example for the term when none was agreed. Catalonia has no civil-law rules of its own for commercial leases, but the general rules of Catalan civil law do apply. For example, unpaid rent becomes time-barred after three years if it is not claimed before then. Lodging the deposit with the “INCASÒL”, the Catalan public body that holds tenancy deposits, is also a Catalan rule. What is not valid even if signed Giving no deposit, giving less than two months' rent or waiving the right to interest on it if the landlord takes more than a month to return it. Requiring the tenant to take out rent guarantee insurance, since 8 October 2026, on the most straightforward reading of the law. Refusing to put the lease in writing if the tenant asks for it. Anything contrary to the law, morality or public order and anything that leaves the validity or performance of the lease in the hands of only one of the parties. Standard terms and conditions, the clauses one party drafts for use in many contracts, if they are not clear or the other party could not have known about them when signing. Only a consumer can argue that a clause is unfair, that is, unbalanced to the detriment of the party who did not draft it. According to the “Tribunal Supremo”, Spain's Supreme Court, someone who rents premises for their business is not a consumer. What is valid for commercial premises but not for a flat For homes, the law renders void any clauses that leave the tenant worse off than it provides. For commercial premises that rule does not exist and the following, among others, are valid: A short term, with no statutory minimum. The tenant's waiver of goodwill compensation. Guarantees in addition to the deposit worth more than two months' rent. The tenant paying the “IBI” (the local property tax) or the letting agent's fees. Rent increases in line with the consumer price index (CPI) or another index, with no cap. Compensation if the tenant leaves early. Works and repairs at the tenant's expense. The tenant's waiver of the right to buy the premises ahead of anyone else if they are sold was also common. Since 8 October 2026 it has been open to challenge, because the reform prohibits that waiver for homes and the law refers to that rule for commercial premises.