Rent increases in Spain: the IRAV index and the 2% rule

No clause, no update

The wording of article 18.1 is plain: during the contract the rent can be updated by landlord or tenant on the date each year of the contract is completed, “en los términos pactados por las partes”, and without an express agreement “no se aplicará actualización de rentas a los contratos”. A contract that is silent therefore keeps the same rent for as long as it lasts, including extensions. A clause that merely says the rent “will be updated annually” is different: the second paragraph of article 18.1 says that where parties agreed a mechanism but did not name the index or method, the update follows the annual change of the IRAV.

What the IRAV is

The LAU’s additional provision 11 instructed INE to define a reference index for annual updates, as a limit meant “to avoid disproportionate rent increases”. INE publishes it as the Índice de Referencia para la Actualización Anual de los Contratos de Arrendamiento de Vivienda. The page read on 15 October 2026 shows:

• Reference month: September 2026
• Annual variation: 2.54%
• Published: 14 October 2026

Article 18.1 sets the cap: whatever the clause says, the increase from an annual update “no podrá exceder” the percentage change of the IRAV at the date of the update, using the reference month corresponding to the last index published on the day the contract is updated. So the figure that applies depends on your anniversary date, not on the one above. The 2.54% is the current value, not a fixed rate for the year.

How to calculate

The formula is: new rent = current rent × (1 + IRAV variation), at most. As a calculation only, not an official example: if the IRAV in force on your anniversary were 2.54% and the clause allowed the full change, a rent of €1,000 could rise by at most €25.40 to €1,025.40. A clause tying the rent to another index (for example a fixed 1% annual rise) is allowed as long as the result does not exceed the IRAV cap.

The temporary rule to 31 December 2027

Final provision 6 of Real Decreto-ley (RDL) 29/2026 applies to leases whose annual update falls between its entry into force (8 October 2026) and 31 December 2027. The tenant “podrá negociar” the update with the landlord, subject to two conditions:

1. If the rent is above the maximum price under the state reference price system (the SERPAVI), “no procederá la aplicación de incremento alguno”: no increase at all.
2. In every other case the increase is whatever the parties newly agree. Failing a new agreement, it cannot exceed 2%.

This is why the 2% figure is a ceiling for the period, not the general rule. Outside the period, the IRAV cap alone applies. The decree-law is in force but, as the consolidated BOE text does not record validation on 15 October 2026, it is subject to validation by the Congress of Deputies; Congress repealed an earlier decree-law with similar content on 2 October 2026.

On the reference price system: a state resolution of 16 April 2026 (BOE of 20 April) updated it, and it sets the maximum rent “tomando el valor superior del rango de valores individualizados” for the home’s location and features. The ministry’s online tool for individual values could not be opened for this guide, so no figure for a specific home is given here.

How to apply an update properly

According to article 18.2, the updated rent is payable from the month after the party concerned notifies the other in writing, stating the percentage applied and, if the tenant asks, attaching an INE certificate. A note on the previous month’s rent receipt is a valid notification. A landlord who simply starts charging more without written notice has not made the update.

Related charges move less

Service charges the tenant has agreed to pay under article 20.1 can rise during the first five years (seven for a company landlord) only by agreement and by no more than twice the percentage by which the rent could rise under article 18.1 (article 20.3). The deposit is not updated during that period either; see the deposit guide.

Successive temporary leases and stressed areas

Where several temporary-housing leases follow each other on the same home, article 17.8 limits the annual percentage rise of each new rent to the IRAV in force. In a declared stressed housing market area, a new contract’s starting rent is also limited, as explained in the guide on stressed housing market areas. Increases for improvements are separate (article 19): after five years of the contract, works can raise the annual rent by the invested capital multiplied by the legal interest rate plus three points, with a ceiling of 20% of the rent then in force.

Which professional to consult

For a dispute over an update, a lawyer registered with a Spanish bar association (colegio de abogados) can compare your clause with article 18. The index values themselves are published by INE; Payotte does not recalculate them for individual contracts.