What companies and individuals should review before accepting the default rate
Excess withholding tax is one of the most common — and most avoidable — cross-border tax problems affecting non-residents with Spanish-source income. In practical terms, the issue usually arises when a Spanish payer applies the domestic withholding rate by default, even though a double tax treaty limits Spain’s taxing rights or the income should not have been taxed in Spain in the first place. Under the Spanish Tax Agency’s own rules, when a non-resident has borne a withholding higher than the tax that actually corresponds, the excess may be reclaimed through Form 210.
This matters for both companies and individuals. For companies, excess withholding often affects dividends, interest, royalties or other cross-border payments connected to group structures and international operations. For individuals, the issue typically appears in Spanish dividends, interest or other investment income where the domestic rate has been applied without proper regard to the applicable treaty. Spain’s domestic framework for non-residents is the IRNR, but that domestic framework must operate alongside the tax treaty network Spain has in force with other jurisdictions.
As explained in our article on double taxation relief in Spain, the key issue is not simply identifying that a treaty exists, but determining how it applies in practice. A treaty may reduce the Spanish withholding rate, allocate taxing rights differently, or in certain cases support the position that the income was not taxable in Spain at all. AEAT’s own instructions for Form 210 expressly contemplate the application of treaty limits, including the percentage cap established in the relevant agreement.
Where excess withholding usually appears
In Spain, the domestic tax rate applicable to non-residents without a permanent establishment depends on the nature of the income and, in some cases, the taxpayer’s residence. AEAT’s current rate tables show that the general rate is 24% for many taxpayers, while 19% applies in several cases, including residents in the EU, Iceland, Norway and Liechtenstein for income categories where that reduced domestic rate is available. AEAT’s guidance also states specifically that the tax rate applicable to dividends and interest is 19% under the non-resident regime, unless relief applies.
That is precisely where the problem begins. The domestic rate is often treated as the end of the analysis, when in reality it should only be the starting point. If a treaty limits the Spanish withholding to a lower rate, or if the income falls outside Spain’s taxing rights under the treaty, the excess is not simply an unfortunate cost. It is, in principle, recoverable. AEAT states this clearly: where the non-resident has suffered a withholding higher than the tax due, the excess can be reclaimed through Form 210.
Companies: the most common corporate scenarios
For companies, excess withholding is often linked to payments that are treated as routine from a treasury or finance perspective, but that are not being reviewed with sufficient treaty analysis.
A first common case is the distribution of dividends by a Spanish subsidiary to a non-resident parent company. If the Spanish payer applies the domestic rate automatically, but the applicable treaty provides for a lower cap, the excess may be refundable. This is closely linked to the issues discussed in our article on repatriating profits from Spain, where we looked at how withholding can unnecessarily reduce group liquidity if the structure is not reviewed in advance.
A second common case concerns interest and royalty payments. Here the treaty analysis is often more sensitive because the tax treatment depends not only on the rate cap, but also on whether the recipient is the beneficial owner and whether the legal and accounting record properly supports the nature of the payment. Where the Spanish payer has withheld at the domestic rate but the treaty would have allowed a lower rate, Form 210 is again the recovery route AEAT provides.
A third scenario appears where the non-resident company takes the view that it has no permanent establishment in Spain, and therefore Spain should not tax the business profits in question under the treaty. If withholding has nevertheless been applied, the issue moves from ordinary compliance into a refund and evidentiary exercise. This is why the treaty analysis and the documentation file need to be built together, not separately. Spain’s treaty framework is designed to allocate taxing rights between states, and not every item of Spanish-source income should automatically remain taxed in Spain.
Individuals: the problem is just as real
Although many cross-border tax articles focus on companies, a large share of real enquiries come from individuals. In practice, the issue is often easier to see: a non-resident individual receives Spanish dividends or interest, sees the Spanish withholding applied, and assumes that is simply the final tax cost.
Very often it is not. If the individual is resident in a treaty jurisdiction and the treaty limits the Spanish withholding, the excess may be reclaimed. AEAT’s system is not limited to corporate claimants; Form 210 is the standard return and refund channel for non-residents without a permanent establishment who need to regularise or reclaim tax in relation to Spanish-source income.
This is also why our article on the Spain–UK double taxation agreement is useful as a companion piece. It shows how a treaty can alter the outcome materially, particularly in a post-Brexit setting where EU directives no longer apply and the treaty becomes the main relief mechanism. The same logic applies more broadly across Spain’s treaty network.
Why refunds are often delayed or missed altogether
In our experience, the legal entitlement to a refund is often not the hardest part. The real difficulty usually lies in the documentation.
The refund claim needs to be consistent not only with the treaty position, but also with the legal and accounting evidence. That typically means the taxpayer must be able to demonstrate residence, the nature of the income, the amount withheld, and — where relevant — beneficial ownership, the absence of a permanent establishment, and the contractual basis for the payment. AEAT’s own instructions for Form 210 reflect this treaty-based logic, and in practice a weak file often leads to delay, additional requests or rejection.
This is one of the reasons why these matters should not be treated as a purely mechanical filing exercise. The refund process may begin with a form, but it is rarely solved by the form alone. Legal and accounting consistency matters.
Refunds matter, but prevention matters more
Where excess withholding has already been suffered, the refund route is clearly important. But from a strategic standpoint, the better result is usually to avoid unnecessary withholding in the first place. That means reviewing treaty eligibility in advance, deciding whether relief can be applied at source, and making sure the relevant certificates and supporting records are ready before the payment is made. AEAT’s framework clearly distinguishes between the domestic tax calculation and the effect of treaty limitations, so there is no reason to accept a default outcome where the legal basis for a better one already exists.
This is also where experience makes a practical difference. Excess withholding claims are not unusual, but resolving them efficiently requires more than identifying the refund box on Form 210. It requires a proper review of the underlying structure, the treaty position and the documentary support. That is the difference between filing a claim and solving the problem.
After the refund: keep the structure under control
Recovering excess withholding is only part of the job. Once the immediate issue has been addressed, the structure should be managed so that the same problem does not reappear in the next payment cycle. Residence certificates need to be kept current. Legal documentation should remain aligned with the actual income flow. Accounting support should be consistent with the treaty article being relied upon. And where the issue touches recurring Spanish-source income, the withholding treatment should be monitored proactively rather than reviewed after the cash has already left.
For that reason, this topic naturally connects with our work in non-resident taxation in Spain. In many cases, what begins as a refund matter ends up being a broader question of how a non-resident individual or business should manage its Spanish tax position on an ongoing basis.
Conclusion
Spain must refund excess withholding tax to non-residents when the tax withheld exceeds what actually corresponds under the applicable legal framework. That sounds simple, but in practice the answer depends on the interaction between domestic non-resident tax rules, treaty limits, the nature of the income, and the quality of the supporting file. AEAT expressly provides a refund mechanism through Form 210, but obtaining the refund is only one part of the equation. The more important issue is making sure the same over-withholding does not happen again.
