If you’re renting in Spain, there’s one rule every tenant should know and many landlords still ignore.

By law, your deposit must be returned within 30 days of handing back the keys. Miss that deadline, and the landlord could end up paying you extra.

This is now a legal obligation under Spain’s latest rental laws, designed to protect tenants once a contract ends.

The deposit itself is standard in most rentals, usually equal to at least one month’s rent.

It’s meant to cover things like damage, unpaid bills or breaches of contract. But it’s not a fee. If the property is returned in good condition, that money should come back to you.

In reality, delays are common as landlords often say they need time to check the property or review utility bills.

However, the law gives them a clear one-month window to carry out those checks.

If the deposit hasn’t been returned within 30 days, it automatically starts generating legal interest, and the tenant doesn’t need to prove a dispute or take action first to get the clock ticking.

That means a landlord could end up paying more than the original deposit, with interest typically sitting around 3 to 4% a year.

And if the deposit wasn’t properly registered with the relevant authority, fines can run into tens of thousands of euros.

There are cases where landlords can keep part of the deposit, but they need solid proof. That means invoices, quotes or clear evidence of damage caused by the tenant. General wear and tear doesn’t count.

Even then, any remaining amount must still be returned within the legal timeframe.

If the money doesn’t come back, tenants have the right to claim it. Usually that starts with a formal written request. If that fails, the case can go to court as a straightforward claim for money owed.