Tax Obligations for British Citizens in Spain: The UK Treaty and What to File

For a British national settling in Spain, the tax picture has two layers that need to be understood separately before they can be managed together: the Spanish regime that applies in Spain, and the bilateral treaty that coordinates the two jurisdictions. Conflating the two leads people to assume they either pay nowhere or pay in both, when the reality is more nuanced and, with the right planning, manageable.

The UK-Spain Double Taxation Treaty: What It Regulates

The Convention between the United Kingdom and Spain for the Avoidance of Double Taxation dates from 1975, with later amending protocols. It remains fully in force after Brexit — bilateral tax treaties were not affected by the UK's departure from the EU — and establishes which country has primary taxing rights over each type of income.

Employment income is taxed in the country where the activity is performed. If you work in Spain for a Spanish company, your salary is taxed in Spain. If you work remotely from Madrid for a UK employer, the rule depends on the duration of the arrangement and whether there is a permanent establishment in Spain, but in broad terms the country where the activity is performed takes priority.

Dividends from UK companies received by a Spanish resident are taxed in Spain, with a cap on withholding at source of 15% that can be offset in the Spanish return. Interest follows similar logic. Business profits of a UK company are taxed in the UK unless there is a permanent establishment in Spain.

The exception that surprises most people: pensions from UK public service employment — civil servants, military, police — are taxed in the UK, not Spain, regardless of where the recipient lives. The standard UK State Pension, however, is taxed in Spain if you are a tax resident there.

When You Stop Being a UK Tax Resident

The UK applies the Statutory Residence Test (SRT) to determine whether someone is or remains a tax resident. It is a test-based system built around the number of days spent in the UK, ties to the country — home, family, work — and years of prior residency.

For most British nationals who relocate to Madrid on a definitive basis, deregistering as a UK tax resident is formalized through form P85 if employed, or through the departure year tax return if self-employed or receiving investment income. HMRC does not have an explicit "deregistration" procedure in the way some European countries do, but filing the P85 and the departure year return documents the change of status.

The year of departure — the UK tax year in which the move takes place, running April to April — requires a return covering only the period as a resident. From the following year, if the SRT criteria are met, UK tax residency ceases.

Tax Obligations in Spain from Year One

Once you are a Spanish tax resident — more than 183 days in the calendar year, or with the core of your economic interests here — the main obligations are the IRPF income tax return and, if applicable, the modelo 720.

IRPF is mandatory if income exceeds 22,000 euros annually from a single payer, or 15,000 euros if there are multiple income sources or capital returns above 1,500 euros. The tax scale in Madrid is progressive up to 43.5%. For high earners the impact can be significant, and planning ahead — including evaluating whether the impatriates regime (Beckham Law) applies — can make a material difference.

The return is filed between April and June of the year following the one it covers. For the first year in Spain, a partial return may be filed if the move occurred mid-year.

The Modelo 720: What It Is and Who Must File It

The modelo 720 is an informational declaration — it does not generate a direct tax payment — of assets and rights held abroad. It is mandatory for Spanish tax residents who hold bank accounts abroad with a balance above 50,000 euros, foreign real estate above 50,000 euros, or foreign securities, insurance and investments above 50,000 euros, per category.

For a British national who retains a UK property after moving to Spain, the modelo 720 is almost certainly required if the property value exceeds that threshold — which is the case for most UK real estate given current market levels.

The filing deadline is between 1 January and 31 March of the year following the first year in which Spanish tax residency is acquired. Non-compliance carries penalties, though the 2026 framework is considerably more moderate than the original one declared partly incompatible with EU law by the European Court of Justice.

The general logic of tax residency transfer — including interactions with EU country treaties — has strong parallels with the British case; the guide on transferring tax residency to Spain for EU citizens covers the shared principles.

For those relocating for professional reasons, the complete guide for British citizens in Madrid also covers visa and initial registration implications. At Aedara, we coordinate fiscal relocation planning for British nationals, including the year-of-transition return. Contact us before you arrive and we will prevent the surprises.