A tool for landlords
Rental deposit calculator (fianza)
Tell me the rent and what you let, and I will tell you how much fianza you may ask for by law, the maximum extra guarantee, and where to lodge it in your región. No sign-up. The fianza is the deposit Spanish law obliges you to take, and in most regions to hand over to a public body.
What are you letting?
Lodging the deposit in Comunidad de Madrid
- Where: Agencia de Vivienda Social (antes IVIMA)
- Deadline: 30 días hábiles desde la firma del contrato
- If you do not: recargo del 2% (5% pasado un año) y posibles multas
What the law says (LAU, art. 36):
- The compulsory fianza is one month's rent for homes and two months' rent for non-residential use (shop, office).
- For homes you may agree an extra guarantee (a bank guarantee or additional deposit) of at most two further months on contracts of up to 5 years (7 if the landlord is a company).
- In most regiones the landlord must lodge the fianza with a public body, each with its own deadline and penalties. The money belongs neither to you nor to the tenant while the contract runs.
Is the flat in Madrid? We cover it in detail there: full guide to the fianza in the Comunidad de Madrid. And if you are preparing the contract, see the documents to ask a tenant for.
Frequently asked questions
How much deposit can I ask for on a flat?
One month's rent. That is the statutory fianza set by article 36 of the LAU for residential lets. On top of that you may agree an additional guarantee of up to two further months on contracts of up to five years, seven if the landlord is a company.
What if I am letting a shop or an office?
Two months' rent as the statutory deposit. For non residential use there is no legal cap on the additional guarantee: the amount is agreed freely in the contract.
Is the additional guarantee the same as the deposit?
No. The fianza is set by law and in most regions has to be lodged with a public body. The additional guarantee (a bank guarantee or an extra deposit) is agreed in the contract, stays with you, and covers damage or arrears beyond the deposit.
Do I have to lodge the deposit with a public body?
In most autonomous regions, yes, and each one has its own deadline and its own penalty if you do not. The calculator gives you the body and the deadline for the region you pick. While the contract runs, that money belongs neither to you nor to the tenant.
When do I have to return the deposit to the tenant?
The obligation starts when the contract ends, and the right thing is to return the balance as soon as you can. The law sets no fixed deadline, but it gives a clear warning: once a month has passed since the keys were handed back and you have not returned what is due, statutory interest starts running in the tenant's favour.
Soycasero keeps track of the fianza for you: it records whether it is lodged or in your custody, and reminds you of your región's deadline and every other date in the contract. Try it free.
Amounts and deadlines are indicative and may change under regional rules; always check your región's official source before signing or lodging. This tool offers general information to orient you, not legal, tax or other professional advice for your individual case. The content has been prepared to the best of our knowledge but is provided without warranty as to accuracy, completeness or how up to date it is. It creates no professional or advisory relationship and does not replace the advice of a lawyer, tax adviser or gestor for your particular situation. Rules change and may vary by comunidad autónoma; the version in force and the guidance of the competent authority always prevail. Liability for decisions you take on the basis of this information is excluded to the extent permitted by law. The content refers exclusively to Spanish law and Spanish procedures. The provider is a Spanish Sociedad Limitada and Spanish law applies to this service, without prejudice to the mandatory consumer protection rules of your country of residence. For your tax obligations at home, including relief under the relevant double taxation treaty, please consult an adviser qualified there. Last updated: July 2026. Full disclaimer and limitations.