IRS Rates September 2026: How Much It Costs to Cancel Your Fixed-Rate Mortgage

Key data

If you have a fixed-rate mortgage and are thinking about canceling it early, the amount the bank can claim from you is not arbitrary: it is set by the Bank of Spain each month through IRS rates (Interest Rate Swap). The Resolution of October 1, 2026 publishes the indices corresponding to September 2026, applicable as mandatory under the Bank of Spain Circular 5/2012.

The same applies to companies with fixed-rate loans or credit facilities: before negotiating an early cancellation with your entity, it is advisable to know these figures.

What does this regulation establish?

The Bank of Spain publishes monthly the IRS rates necessary to calculate market value in two specific situations:

• Interest rate risk compensation in fixed-rate mortgage loans.
• Differential applicable in early cancellations of loans or credit facilities.

IRS rates (Interest Rate Swap) reflect the cost at which the market exchanges fixed-rate flows for variable-rate flows at different maturities. If you cancel your fixed-rate mortgage early, the bank loses the interest it expected to collect. The compensation it can claim is calculated by comparing your mortgage rate with the IRS for the term equivalent to the remaining loan period.

The rates published for September 2026 are as follows:

The IRS curve shows a relatively flat shape in the long segments, indicating that the market does not expect major movements in interest rates over the long term. This has a direct consequence: the difference between your fixed mortgage rate (signed when rates were lower) and the current IRS may be smaller than it was one or two years ago, which potentially reduces the compensation the bank can demand from you.

Economic and operational impact

The compensation for early cancellation of a fixed-rate mortgage can be significant. It depends on three factors:

• The outstanding capital to be amortized.
• The difference between your fixed mortgage rate and the IRS for the residual term.
• The remaining term until maturity.

With IRS rates for September 2026 between 3.129% and 3.595%, anyone who signed a fixed-rate mortgage at 1.5% or 2% five or six years ago will see that the current IRS exceeds their contracted rate. In that case, the compensation the bank can charge is zero or very minimal, because the bank can reinvest that money at a better rate than it was charging you.

Conversely, someone who signed at 3.8% or 4% and has more than ten years of mortgage remaining could face significant compensation, as the bank loses margin by receiving the money early and can only reinvest it at 3.595% (IRS at 15 years).

Who does it affect?

• Individuals with fixed-rate mortgages considering early cancellation, total or partial.
• Companies and self-employed with fixed-rate mortgage loans wanting to settle debt before maturity.
• Financial entities (banks, savings banks, credit cooperatives) that must apply these indices mandatorily when calculating compensation.
• Financial advisors, wealth managers and lawyers advising clients on refinancing or cancellation operations.
• CFOs and financial directors of companies with fixed-rate mortgage debt on balance sheet.

Practical example

Imagine a company that signed in 2021 a fixed-rate mortgage loan at 1.80% for €500,000, maturing in 2036 (15 years from signing). In October 2026, it has approximately 10 years of loan life remaining and outstanding capital of €380,000.

To calculate whether the bank can charge compensation, the loan rate (1.80%) is compared with the IRS for the equivalent residual term. If the residual term is 10 years, the applicable reference IRS would be around 3.4%-3.5% (between the 1-year value of 3.129% and the 15-year value of 3.595%, interpolating).

Since the market IRS (≈3.4%) is higher than the loan rate (1.80%), the bank can reinvest the recovered capital at a better rate. In this case, the regulation establishes that no compensation is due to the bank, or it is minimal. The company could cancel early without significant cost for this concept.

The opposite scenario would occur if the company had a fixed rate of 4% and the residual IRS was 3.5%: there would be compensation in favor of the bank, calculated on that 0.5% difference applied to the outstanding capital and remaining term.

What should companies do now?

1. Locate your fixed-rate mortgage loans and note the contracted interest rate and residual term for each one.
2. Compare your fixed rate with the published IRS for the term equivalent to the time remaining on your loan. If the IRS exceeds your rate, canceling early may have no compensation cost.
3. Request the official calculation from your financial entity of the compensation for early cancellation, requiring them to apply the IRS indices from the Bank of Spain Resolution for the current month.
4. Verify that the bank correctly applies Circular 5/2012: if the figure they offer does not match the published rates, you have grounds to claim.
5. Assess the optimal cancellation timing with your financial advisor: with a relatively flat IRS curve, the differences between canceling now or in the coming months may be small, but it is advisable to monitor the Bank of Spain's monthly publication.

Official source

Consult complete regulation in official source

Disclaimer: This article is purely informational in nature and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-21237