British Citizen in Spain — Meet Your Tax Obligations in Both Countries and Optimise Your Tax Position

The Legal Framework: Spain-UK Double Tax Treaty

The bilateral tax relationship between Spain and the UK is governed by the Convention between the Government of the Spanish State and the Government of the United Kingdom of Great Britain and Northern Ireland for the Avoidance of Double Taxation and the Prevention of Fiscal Evasion with Respect to Taxes on Income and on Capital, signed in London on 21 October 1975 and in force since 18 July 1977 (BOE No. 270, 10 November 1977).

This convention, which broadly follows the OECD Model albeit with features typical of the era in which it was negotiated, allocates taxing rights between both states. Following Brexit, the convention remains in force between the UK (now a third state with respect to the EU) and Spain, and is the only instrument protecting taxpayers of both countries from double taxation.

Legal reference: Instrument of Ratification, BOE-A-1977-14347 and Amending Protocol of 1994 (BOE-A-1994-28000).

The Five Main Tax Obligations of a British Citizen in Spain

1. Tax Residency and the 183-Day Rule

The first step is to determine when and how you become a Spanish tax resident. Article 9 of the LIRPF sets out two alternative criteria: (a) spending more than 183 days in Spanish territory during the calendar year, or (b) having in Spain the main hub or base of your activities or economic interests.

The 1976 DTT includes tiebreaker rules in article 4 to resolve dual residency conflicts: permanent home, centre of vital interests, habitual place of residence and nationality, in that order of priority.

Practical implication: a British citizen who spends more than six months a year in Spain but maintains their UK domicile may be considered a tax resident in both countries. The DTT resolves the conflict, but the resolution has significant tax consequences that must be planned before the move.

2. ISAs (Individual Savings Accounts) in Spain

ISAs are the most popular tax-exempt savings vehicle in the UK. In the 2025/26 tax year, the annual contribution limit is £20,000. Returns generated within an ISA (interest, dividends, capital gains) are completely tax-exempt in the UK.

In Spain, this exemption does not exist. From the first day of Spanish tax residency, all returns generated within the ISA (dividends, interest, capital gains from asset sales) are taxed in the IRPF as capital income or capital gains, depending on their nature. The effective rate ranges from 19% to 28% on the savings base (2026).

The AEAT treats the ISA as an ordinary securities account. No treaty, EU regulation or OECD instrument obliges Spain to recognise the UK tax exemption.

Planning tip: if possible, realise any unrealised gains within the ISA before transferring residency to Spain, while the UK exemption still applies. Once resident in Spain, ISA management must be conducted with full awareness of the IRPF implications.

3. British Pensions: State Pension, SIPP and QROPS

Pensions are the most complex area for British expats in Spain.

New State Pension: Under article 18.1 of the DTT, pensions paid in respect of past employment are taxed in the state of residence of the beneficiary. If you are resident in Spain, the British State Pension is fully taxed in Spanish IRPF as employment income. HMRC may initially withhold tax; the process to eliminate that withholding involves requesting the Spain/Individual form and evidencing Spanish tax residency.

SIPP (Self-Invested Personal Pension): Income generated within the SIPP (dividends, interest) is not taxed in Spain while it remains in the plan. Taxation is triggered when capital is withdrawn: the benefit is taxed as employment income in the IRPF. Article 18.2 of the DTT provides that pensions paid under UK social security legislation may also be taxed in the UK, but Spain applies the international double taxation deduction.

QROPS: Transfers from a UK plan to a QROPS in Spain may trigger the Overseas Transfer Charge (25%) from HMRC if the exemption conditions are not met. Since Brexit, the UK no longer considers Spain as an EEA state, which complicates the structure. Professional advice is essential before initiating any transfer.

4. The Beckham Law for British Professionals

The special expatriate regime under article 93 LIRPF — the Beckham Law — allows professionals relocating to Spain for work to pay a flat 24% on Spanish-source income (up to €600,000) for six years, with foreign-source income exempt.

For a British professional relocating to Madrid with an annual salary of €150,000, the difference between standard IRPF (marginal rate of 47%) and the Beckham regime (flat 24%) represents an annual saving of approximately €34,500 — over €200,000 over the full six-year period.

Key requirements for UK citizens:

• Must not have been a Spanish tax resident in any of the ten preceding tax years before the move.
• Must relocate to Spain for work reasons (employee, self-employed, director, digital nomad or startup visa holder).
• Must file Modelo 149 with the AEAT within six months of the start of activity.

5. The Modelo 720 and Declaration of Foreign Assets

The Modelo 720 is the informational declaration of assets and rights located abroad that Spanish tax residents must file when the value exceeds €50,000 in any of three categories:

1. Bank accounts at non-resident financial institutions.
2. Securities, rights, insurance and income deposited, managed or obtained abroad.
3. Real estate and rights over real estate located abroad.

For a British citizen with an ISA, a SIPP, a current account and a property in the UK, the Modelo 720 obligation is very likely to be triggered in more than one category.

The CJEU (judgment of 27 January 2022, case C-788/19) declared the most severe penalties in the original Spanish draft disproportionate. The Spanish government amended the rules in 2023, but the reporting obligation remains in force and non-compliance can lead to formal penalties and investigation proceedings.

Key Post-Brexit Changes for UK Citizens in Spain

Brexit changed several rules that directly affect British citizens:

Common Mistakes and How to Avoid Them

British citizens frequently make these tax mistakes in Spain:

Mistake 1: Assuming HMRC will stop taxing them once they are Spanish residents. Incorrect — HMRC applies initial withholdings that must be actively eliminated through the Spain/Individual form process. Until that is done, tax is being paid in two countries simultaneously.

Mistake 2: Failing to declare the ISA in the IRPF. The AEAT has access to foreign banking information via the CRS (Common Reporting Standard). ISAs must be declared in Annex D of the IRPF return (foreign-source income).

Mistake 3: Transferring a SIPP to Spain without analysing the QROPS and the Overseas Transfer Charge. A poorly planned transfer can trigger a 25% HMRC withholding that is not recoverable.

Why BMC

BMC has a specialist team for UK expats with experience in the 1976 DTT, coordination with HMRC, and the treatment of British financial and pension products within the Spanish tax system. We manage full compliance: IRPF, Modelo 720, Wealth Tax and coordination with UK advisers.

Contact the BMC tax team for an initial consultation on your specific situation.