Mortgage interest rates April 2026: what indices does the Bank of Spain publish

Key data

If you have a variable rate mortgage or manage a portfolio of mortgage loans, the indices published by the Bank of Spain on 17 April 2026 are the reference values that will determine the amount of your next payments. It is not a regulation that enters into force in the future: it is already in force.

The Resolution of 17 April 2026 from the Bank of Spain complies with the regulatory obligation to publish these indices monthly, which are binding for all financial entities operating with mortgages referenced to them.

What does this regulation establish?

The Bank of Spain is obliged by the regulations governing the mortgage sector to publish monthly the official reference interest rates for the mortgage market. This April 2026 resolution includes the following official indices:

These values are not indicative: financial entities are legally obliged to use them in the review of mortgage loans that are referenced to each of them.

Economic and operational impact

The monthly publication of these indices has direct economic consequences for two groups:

For variable rate mortgage holders: each time the loan review date arrives (usually annual or semi-annual), the entity applies the official index in force at that time plus the spread agreed in the contract. A movement up or down in EURIBOR, for example, can translate into tens or hundreds of euros difference in the monthly payment.

For financial entities: the obligation to use these official indices eliminates any margin of discretion in the review. They cannot apply a different index or a value different from that published by the Bank of Spain. Failure to comply with this obligation has regulatory consequences.

The review of indices is monthly, which means that the April 2026 values will be the reference for all mortgage reviews that occur during this period.

Who does it affect?

• Holders of variable rate mortgages referenced to EURIBOR, MIBOR or other official indices published by the Bank of Spain.
• Financial entities and banks with portfolios of variable rate mortgage loans, obliged to apply these indices in periodic reviews.
• Financial and mortgage advisors who accompany clients in the review or negotiation of mortgage conditions.
• Real estate developers and companies in the sector that finance operations with loans referenced to these indices.
• CFOs and financial directors of companies with mortgage financing on their balance sheet.

Practical example

Imagine a company that has a variable rate mortgage loan on its facilities referenced to EURIBOR plus a spread of 0.75%. The annual review of the payment occurs in May 2026.

To calculate the new applicable rate, the financial entity will take the value of the EURIBOR published by the Bank of Spain in the Resolution of 17 April 2026 (reference BOE-A-2026-8586) and add the spread agreed in the contract. That result is the interest rate that will be applied for the next twelve months.

If the CFO of that company consults the BOE before the review, they can anticipate exactly how much the monthly payment will vary and plan the treasury in advance, without waiting to receive the bank's notification.

The same applies to an individual with a variable rate mortgage: knowing the index published in April 2026 allows you to calculate the new payment before the bank issues the review letter.

What should companies do now?

1. Consult the values published in the BOE (BOE-A-2026-8586) to know the exact value of EURIBOR, MIBOR and other official indices for April 2026 before the next mortgage review.
2. Identify which mortgage loans are approaching review and calculate the impact on the monthly payment by applying the published official index plus the contractual spread.
3. Verify that the financial entity applies the correct index: if you receive a review notification, check that the rate applied matches the one published by the Bank of Spain for this period.
4. Update treasury projections if the variation in the index represents a relevant change in monthly or annual financing costs.
5. Seek advice on possible alternatives if the current level of indices makes it advisable to study a subrogation, novation or change to a fixed rate, depending on market conditions.