The rent on a Spanish residential lease can only be updated once a year, on the anniversary of the contract, and only if the contract provides for it. If the lease was signed on or after 26 May 2023, the increase can't exceed the IRAV; if it's older, what was agreed applies, usually the IPC (Spain's consumer price index, CPI). With the September 2026 IRAV (2.54%), a rent of €900 becomes €922.86 a month.
The rent update calculator does the sum with official INE data and tells you which reference month to use. In this guide you'll see why, with worked examples.
When can the rent be updated?
Article 18 of the Urban Leases Act (LAU) (in Spanish) sets three conditions:
- Only on the anniversary. The rent is updated “on the date each year of the contract's term is completed”, not at the start of the year or when a high CPI figure comes out.
- Only if it was agreed. “In the absence of an express agreement, no rent update shall apply.” If the contract says nothing, the rent stays the same until the lease ends.
- On the agreed terms and without exceeding the legal caps. If the contract says the rent will be updated but doesn't name the index, the Competitiveness Guarantee Index (IGC) is used, which by law is taken as between 0% and 2%.
Which index applies, depending on the lease date?
The signing date decides which rules still apply to that lease:
| Lease signed | Index that applies | Legal cap on the increase |
|---|---|---|
| From 26/05/2023 | The agreed one (IRAV, CPI, a percentage…) | The IRAV, for updates from 1/01/2025 |
| 6/03/2019 to 25/05/2023 | The agreed one, almost always CPI | CPI |
| Before 6/03/2019 | The agreed one | None as a general rule (except 19/12/2018 to 23/01/2019: CPI) |
The CPI cap was introduced by Royal Decree-law 7/2019, and earlier leases keep their own regime. The IRAV arrived with Law 12/2023 on the right to housing, whose fourth transitional provision keeps earlier leases under the regime they had, unless the parties agree to adapt them (both in Spanish).
There were also temporary caps for all leases. Between 31/03/2022 and 31/12/2023, without a new agreement with the tenant, the increase couldn't exceed the change in the IGC (in practice, 2% at most). In 2024 the cap was 3%. If the landlord was a large owner (gran tenedor), the cap applied even with an agreement (article 46 of Royal Decree-law 6/2022, in Spanish).
One point the law leaves half-finished: article 18 still names CPI as the cap. The IRAV comes in through the eleventh additional provision of the LAU, which sets it “as the reference limit for the purposes of article 18”. The INE and the Ministry of Housing apply it to leases signed from 26/05/2023, and that's the approach this guide follows.
What is the IRAV and how does it differ from CPI?
The IRAV (reference index for the annual update of residential lease contracts) has been published monthly by the INE, Spain's statistics office, since January 2025, on the same day as CPI. It's defined in the INE Resolution of 18 December 2024 (in Spanish):
IRAV = the lowest of: headline CPI · core CPI · 2 + 0.5 × (each of them − 2)
The first two are the annual changes the INE publishes. The third part halves whatever inflation exceeds 2%. So while headline and core CPI are below 2%, the IRAV equals the lower of the two; when they rise, the IRAV rises much less. In September 2026 CPI was 4.9% and the IRAV 2.54%.
In practice, on a €900 rent, the difference in September 2026 was €44.10 a month with CPI against €22.86 with the IRAV.
Which month of the index do you use?
Article 18.1 is precise: the month corresponding to the latest index published on the update date. It isn't the anniversary month (that figure doesn't exist yet), nor the latest figure you happen to see when you do the sum weeks later. Since the INE publishes each month around the middle of the next, the figure that applies depends on the day of the anniversary:
| Lease anniversary | Latest IRAV published that day | Value |
|---|---|---|
| 15/09/2026 to 13/10/2026 | August 2026 (published 15/09/2026) | 2.47% |
| 14/10/2026 to 12/11/2026 | September 2026 (published 14/10/2026) | 2.54% |
| 13/11/2026 to 14/12/2026 | October 2026 (published 13/11/2026) | Pending |
If your lease names another month, for example “the CPI for the month of signing”, the contract prevails, as long as the result doesn't exceed the legal cap. The flash CPI estimate the INE publishes at the end of each month isn't the final figure and can't be used for updates.
How is the new rent worked out in practice?
New rent = current rent × (1 + index change ÷ 100)
1. A 2024 lease with the IRAV. Rent of €900, lease signed on 20/09/2024. On 20/09/2026 the latest published IRAV is August's, 2.47%: 900 × 1.0247 = €922.23, €22.23 more a month and €266.76 a year. If the contract said “CPI”, the result would be the same: the 4.3% is capped at the IRAV.
2. A 2021 lease with CPI. Rent of €750, signed on 10/03/2021, anniversary on 10/03/2026. On that day the latest published CPI was January 2026 (2.3%, published 13/02/2026); February's came out on 13/03/2026, three days too late. New rent: 750 × 1.023 = €767.25. The IRAV doesn't apply because the lease predates May 2023.
3. The same lease in 2023. On 10/03/2023 the January 2023 CPI was 5.9%, but the temporary cap was in force: without a new agreement, the increase couldn't exceed the change in the IGC, which is taken as 2% at most. On €750, the rent went to €765.00 instead of €794.25.
Open this example in the calculator
The button loads the first example. For the others, change the rent to 750, the signing date to 10/03/2021, the anniversary to March 2026 (or 2023) and choose the CPI option.
How do you notify the tenant?
The update doesn't apply by itself. Article 18.2 of the LAU says the updated rent is payable from the month after the one in which it's notified in writing, stating the percentage applied. A note on the previous month's receipt is enough, and the tenant can ask for the INE certificate with the figure.
- State the lease date, the index, the reference month, the percentage and the new rent.
- Give notice in the anniversary month to charge it from the following month. If you notify later, it's charged from the month after the notice.
- Keep proof of sending (email, burofax or the signed receipt).
The calculator drafts a factual notice with those details so you only have to check and sign it. The notice text is in Spanish, as the tenant will normally need it.
What happened with the October 2026 decrees?
On 30 September 2026 the BOE (Spain's official gazette) published Royal Decree-law 26/2026, which wrote the IRAV into article 18 and added a 2% cap until the end of 2027 (no increase at all if the rent exceeded the reference price index). On 1 October came Royal Decree-law 27/2026, on lease extensions. Parliament (the Congreso) revoked both on 2 October (BOE-A-2026-20526 and BOE-A-2026-20527; all in Spanish). The rules in the table above are the ones in force today. The 2% cap was only in force on 1 October; if your anniversary fell on that day, get advice.
Run your own numbers
Enter the rent, the signing date and the anniversary. The calculator picks the index month, applies whichever caps apply and drafts the notice for the tenant.
Open the rent update calculator See how it affects your yield
For information only; this is not legal or financial advice.