The rent update index rises to 2.54% in September, its highest value since 2024, while the decree caps reviews at 2%

15/10/2026 – ⏱ 3 min

This article is for informational purposes only and does not, under any circumstances, constitute an investment recommendation or financial advice.

The National Statistics Institute (INE) published on 14 October 2026 the reference index for updating rents for September: 2.54%. It is the highest value since the indicator began to be compiled, in November 2024, and the first time it has exceeded 2.5%. In August it stood at 2.47%, so the index rose by seven hundredths of a point in one month. The figure came on the same day that headline inflation was reported to have closed September at 4.9%, and a few days before Congress decides on the decree that caps rent reviews.

What the index is and whom it affects

The rent update index is the indicator that the INE compiles at the request of the Right to Housing Act to prevent disproportionate increases in annual rent reviews. According to the published information, its calculation combines the CPI, core inflation and an adjusted average with a moderating coefficient, and the final result is the lowest of those indicators. In general it applies to main-residence contracts signed since 25 May 2023, the date the law came into force; earlier contracts may keep clauses linked to the CPI. For a review to be possible, the contract must provide for it, a year must have passed since signing or since the last update, and the landlord must give notice in writing. The new rent may be charged from the month following the notice.

The series: from a low of 1.90% to a high of 2.54%

Since its creation, the index has ranged between 1.90% in May 2025 and 2.48% in May 2026, until the September reading broke through that ceiling. The series has shown an upward trend since the 2.14% of January 2026, with 2.44% in June and 2.47% in August as the previous steps. The index remains below headline inflation, which was 4.9% in September, and core inflation, at 3.1%, precisely because of the moderating coefficient that sets it apart from a straight CPI.

An example in euros

On a rent of 1,000 euros a month, a 2.54% review would mean a maximum of 25.40 euros more per month (1,025.40 euros), i.e. 304.80 euros a year. A review in line with the headline CPI of 4.9% would have added around 49 euros a month. The difference between the two references illustrates the practical effect of the index as a cap.

The decree sets a 2% cap

The actual application of the index currently depends on Royal Decree-Law 29/2026, in force since 8 October, which sets a maximum of 2% for rent reviews where there is no agreement between the parties. On 1,000 euros, the cap means 20 euros a month, 5.40 euros less than with the 2.54% index, or 64.80 euros less a year. The rule also protects tenants who already pay above the reference price for their home from increases until 31 December 2027. The Permanent Deputation of Congress will vote on the decree on Friday 16 October: if it is validated, the cap will remain in place until the end of next year; if not, contracts would once again be governed by what was agreed and by the ordinary limits.

Context: inflation and financing

The INE attributed the rise in inflation in September, from 4.3% in August to 4.9%, mainly to fuel and package holidays; transport rose by 10.5% year on year. Meanwhile, the 12-month Euribor was hovering around 3.19% on 14 October, after closing September with an average of 3.247%. An environment of high prices and more expensive financing is the backdrop against which the index reaches its high.

Reading for investors

The index does not measure the market price of rent, but the maximum to which a rent already under contract can be revised, so its evolution affects the income of those who let under existing contracts and not the price of new lettings. In addition, regulatory uncertainty is significant: the effective 2% cap depends on the decree being validated, and a change in that scenario would alter the applicable reviews. Past results do not anticipate future ones, and all real estate investment carries risks of illiquidity, default, regulatory change and total or partial loss of capital. At European level, the activity of crowdfunding platforms is governed by Regulation (EU) 2020/1503 and, in Spain, by the implementing rules and the supervision of the CNMV.

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