Intercompany loans in Spain: arm’s length rate, documentation and tax treatment

A parent company in Germany lends €5 million to its Spanish subsidiary — interest-free. Simple and convenient. Two years later, Spain’s tax authority (AEAT) audits the subsidiary and determines that an arm’s length interest rate should have been charged. The result: a transfer pricing adjustment, a 25% corporate tax bill on the imputed interest income — and a penalty on top. This scenario plays out more often than most finance directors expect.

Intercompany loans between related parties in Spain are subject to Spain’s transfer pricing rules under Article 18 of the Corporate Income Tax Law (Ley del Impuesto sobre Sociedades). The core requirement is straightforward: the interest rate on any loan between related companies must be what two independent parties would have agreed in comparable circumstances — the arm’s length rate. Here is how that works in practice.

What is an arm’s length interest rate for intercompany loans in Spain?

The arm’s length principle requires that intercompany loans be priced as if the borrower and lender were unrelated parties dealing freely in the market. For interest rates, this means the rate must reflect:

• The creditworthiness of the borrower (not the parent group’s credit rating, but the standalone rating of the Spanish entity)
• The currency, term, and amount of the loan
• The seniority and security of the debt
• Market conditions at the time the loan was entered into

In practice, the most commonly used method for setting arm’s length rates on intercompany loans is the Comparable Uncontrolled Price (CUP) method — finding comparable loans between unrelated parties in similar conditions. Benchmarking databases (such as Bloomberg, LoanConnector, or EURIBOR-based reference rates) are typically used to support the analysis.

What does the AEAT look for in intercompany loan audits?

Spain’s tax authority focuses on several key areas when reviewing intercompany financing arrangements:

Interest rate: too low or zero

A zero-rate or below-market loan from a parent to a Spanish subsidiary will be treated as if arm’s length interest had been charged. The AEAT will impute income to the lender (or additional expense relief to the borrower) based on what a market rate would have been. Interest-free loans are a red flag in every Spanish transfer pricing audit.

Interest rate: too high

The reverse also happens: if a foreign parent charges its Spanish subsidiary an above-market rate, the excess interest may be disallowed as a deduction in Spain — reducing the Spanish entity’s tax deduction and increasing its taxable profit.

Thin capitalisation and interest deduction limits

Spain imposes a 30% EBITDA limitation on net financial expense deductions (under Article 16 of the Corporate Income Tax Law, implementing the EU ATAD directive). This means that even if the interest rate is arm’s length, the deduction for net interest expense is capped at 30% of the taxable EBITDA. A minimum threshold of €1 million of net interest expense per year is not subject to this cap.

Hybrid instruments

Loans that have equity-like features (profit participation, convertible instruments, subordinated debt) are subject to additional scrutiny. Spain applies specific rules on hybrid mismatches under ATAD 2 that can deny deductions for payments that are not taxed in the counterparty country.

Transfer pricing documentation for intercompany loans in Spain

All intercompany loans between related parties must be documented as part of the transfer pricing documentation framework. For each intercompany loan, the local file (Archivo Local) must contain:

• Description of the loan: amount, currency, term, interest rate, repayment schedule, and security
• Functional analysis: the roles of lender and borrower, risks assumed by each party
• Benchmarking analysis: evidence that the rate is consistent with market rates for comparable transactions
• Copy of the loan agreement (contrato de préstamo intercompañía)
• Evidence of actual cash flows: bank transfers, account statements

The loan agreement itself should be signed before or at the time the loan is made — backdated agreements are not only ineffective against the AEAT but may also raise fraud concerns.

Withholding tax on interest paid to non-residents

When a Spanish company pays interest to a foreign related party, Spanish withholding tax applies:

• General domestic rate: 19% on interest paid to non-residents
• EU residents: 0% withholding under the EU Interest and Royalties Directive (for qualifying associated companies with 25%+ shareholding held for 2+ years)
• Treaty rate — Spain–Germany: 10% maximum
• Treaty rate — Spain–US: 10% maximum
• Treaty rate — Spain–UK: 12% maximum

To apply a reduced treaty rate, the lender must provide a valid certificate of tax residence to the Spanish borrower before payment is made. Without this, the domestic 19% rate applies and a refund claim must be filed separately.

Can a Spanish company deduct interest paid to a related party?

Yes — subject to the arm’s length requirement and the 30% EBITDA cap mentioned above. Additionally:

• Interest is only deductible if it relates to financing used for business purposes (not for the acquisition of intra-group stakes in certain anti-avoidance scenarios)
• Article 15 of the Corporate Income Tax Law disallows deductions on interest paid to related parties in tax havens
• Hybrid mismatch rules may disallow deductions on payments that generate no corresponding tax income in the counterparty jurisdiction

Advance Pricing Agreements (APAs) for intercompany financing

For high-value or complex recurring intercompany loan structures, an Advance Pricing Agreement (Acuerdo Previo de Valoración) with the AEAT provides certainty on the accepted rate methodology for an agreed period. Spain offers both unilateral APAs (with AEAT only) and bilateral APAs (negotiated between AEAT and a foreign tax authority under a double taxation treaty). Bilateral APAs eliminate the risk of double taxation and are particularly valuable for large intercompany financing programmes.

Frequently asked questions

Does every intercompany loan need a formal written agreement?

Yes. A written loan agreement is the minimum required to demonstrate the existence and terms of the loan. Without one, the AEAT may reclassify the transaction as a capital contribution rather than debt — with very different tax consequences. The agreement should specify: loan amount, currency, interest rate (and how it is calculated), repayment schedule, default provisions, and governing law.

What happens if the Spanish subsidiary cannot pay the interest?

If the Spanish subsidiary genuinely cannot service the intercompany debt, this is itself evidence that the loan may not be arm’s length — an independent lender would typically not extend credit to a borrower unable to service it. The AEAT may reclassify the loan as equity and disallow the interest deductions. Careful economic analysis of the borrower’s repayment capacity should be conducted before the loan is structured.

Is EURIBOR an acceptable reference rate for euro-denominated intercompany loans?

EURIBOR (Euro Interbank Offered Rate) is commonly used as a base reference rate for euro-denominated loans. However, EURIBOR alone is not an arm’s length rate — it represents the risk-free interbank rate. A credit spread must be added to reflect the specific credit risk of the Spanish borrower. The total rate (EURIBOR + credit spread) is what must be benchmarked against comparable third-party transactions.

Getting intercompany loan pricing right in Spain requires both technical knowledge and practical benchmarking. At Capital Auditors & Consultants, we advise on arm’s length rate analysis, intercompany loan documentation, and transfer pricing compliance for multinational groups with Spanish operations. Contact our international tax team before your next intercompany financing is put in place.