Understanding the UK–Spain Double Tax Treaty
What is a double taxation agreement?
A double taxation agreement (DTA) is a treaty between two countries that decides which one has the right to tax a given type of income, and how relief is given when both have a claim. It does not stop you declaring income in two places. What it does is make sure you are not taxed twice on the same money.
When did the current treaty take effect?
The current convention was signed in London on 14 March 2013 and entered into force on 12 June 2014, replacing the earlier convention signed in 1975. The effective dates vary by tax, and this is where most summaries get it wrong:
- Withholding taxes: from 12 June 2014, in both countries.
- In Spain, for income taxes and other taxes: from 1 January 2015.
- In the UK, for income tax and capital gains tax: from 6 April 2015. For corporation tax: from 1 April 2015.
Brexit did not affect the treaty. It is a bilateral agreement that predates EU withdrawal, and both HMRC and the Agencia Tributaria continue to apply it. The full text is published on gov.uk.
Which types of income does it cover?
- Pensions and state benefits
- Rental income from UK or Spanish property
- Interest and dividends
- Capital gains
- Employment income
Each category has its own rule, and the rule depends on your tax residency.
How the Treaty Affects British Residents in Spain
Pensions: the exception that catches people out
If you are retired in Spain and receiving a UK state pension or a private or occupational pension, you generally pay tax in Spain, your country of residence, and not in the UK.
But there is a significant exception that affects a lot of British residents on the Costa del Sol. Pensions paid in respect of government service, which typically includes civil servants, the armed forces, police and some teachers, remain taxable only in the UK. The exception does not apply if you are a Spanish national, in which case the pension is taxed in Spain.
This matters because it is not always obvious which category a pension falls into, and someone with both a Crown pension and a private one may find each is taxed in a different country. It is worth establishing which you have before you assume anything.
Rental income from UK property
This is where the general “you pay tax where you live” rule does not apply.
Income from immovable property may be taxed in the country where the property is located. So if you are tax resident in Spain and rent out a flat in the UK, the UK keeps the first right to tax that income. You then declare the same income on your Spanish return, and Spain gives you a credit for the UK tax already paid.
The practical effect is that you are not taxed twice, but you will usually end up paying whichever of the two rates is higher, and you will be filing in both countries. Several of my clients have been surprised by this, having assumed that becoming resident in Spain moved everything to Spain.
Interest, dividends and capital gains
Interest and dividends are generally taxable in your country of residence, though the treaty allows limited withholding at source on dividends.
Capital gains follow a similar logic to rental income: gains on immovable property can be taxed in the country where the property sits. A Spanish resident selling a UK property will normally face UK capital gains tax on the disposal and then declare the gain in Spain with credit for the UK tax.
Which tax returns do you actually file?
This is where I see the most confusion, so it is worth being precise about the forms.
If you are tax resident in Spain, you file the Modelo 100, the Spanish income tax return, and you declare your worldwide income on it. That includes UK pensions, UK rental income, interest and dividends. There is no separate form for foreign rental income: it goes inside the Modelo 100.
If you are not tax resident in Spain but own property here, you file the Modelo 210, the non-resident income tax return. You file it whether or not you rent the property out, because Spain applies an imputed income to unrented second homes.
The Modelo 210 is the non-resident form. If you are resident, it does not apply to you.
If you remain UK tax resident, or you are resident in Spain but still have UK-source income with tax withheld, you may also need to file a UK self-assessment return with HMRC.
Tax residency and common misconceptions
Spending more than 183 days in Spain in a calendar year usually makes you a Spanish tax resident, but days are not the only test. Spain also looks at where your main economic interests sit and, in some cases, where your spouse and dependent children live.
The most common misconception I hear is that residency follows property ownership. It does not. Buying a home in Spain does not make you tax resident, and renting rather than owning does not protect you from becoming one. It is about time, ties and circumstances, which is why I recommend getting advice before the move rather than after the first tax year has closed.
Two Obligations British Residents Often Miss
Declaring overseas assets: Modelo 720 and 721
If you become tax resident in Spain and keep assets abroad, you may have to file the Modelo 720, an informational declaration of overseas accounts, securities and property. It is triggered when any of the three asset categories exceeds €50,000, and once filed it only needs repeating when a category grows substantially. A separate Modelo 721 covers cryptoassets held abroad.
The penalty regime attached to the Modelo 720 was struck down by the Court of Justice of the European Union in 2022 for being disproportionate, and Spain has since revised it. The obligation to declare, however, remains. For a British buyer who keeps a UK property, an ISA portfolio and a pension pot, this is usually the single most overlooked filing.
Wealth tax and the solidarity tax
Andalusia applies a 100% rebate on the regional wealth tax, which is one of the reasons the region attracts international buyers. But the rebate does not cover everything.
The state-level Impuesto Temporal de Solidaridad de las Grandes Fortunas applies to net wealth above €3 million and is not neutralised by the Andalusian rebate. Non-residents are liable on their Spanish assets, with a €700,000 allowance. There is also a separate threshold at which a wealth tax return must be filed even when no tax is due.
For most buyers this is irrelevant. For anyone purchasing at the upper end of the Costa del Sol market, it is worth modelling before you commit, because the structure of ownership can make a difference.
Real Estate and Double Taxation: What Buyers Should Know
Buying a home in Spain: what to declare and where
Buying does not make you a resident by default, but it does create obligations. Non-residents who own Spanish property must file an annual Modelo 210 even if the property is never let, because Spain imputes a notional income to it based on the cadastral value.
The purchase itself carries its own taxes, which are separate from anything in this guide. I cover those in my article on what taxes apply when buying property in Spain, and if you are buying new build, the AJD stamp duty in Andalusia deserves its own look.
If you rent out a Spanish property
Rental income from a Spanish property is taxable in Spain regardless of where you live. Residents declare it in the Modelo 100; non-residents in the Modelo 210, filed quarterly. If you are UK resident, you then declare the same income to HMRC and claim relief for the Spanish tax paid.
My experience helping British clients
Most of the British buyers I work with arrive with a vague worry about being taxed twice and leave with a clear picture once someone has sat down and separated the categories.
One couple I worked with in Manilva were convinced their UK pension would be taxed in both countries. It was a private pension, so Spain had sole taxing rights and the worry was unfounded. Had it been a Crown pension, the answer would have been the opposite, which is exactly why I do not give that answer from memory and always send clients to a tax adviser to confirm.
How to Claim Relief Under the Treaty
The DT-Individual form
If UK tax is being withheld on income that the treaty says should be taxed in Spain, HMRC’s DT-Individual form is how you claim exemption going forward or a refund of tax already deducted. You will need to prove Spanish tax residency with supporting documentation. HMRC publishes guidance notes for the Spain form.
What documents you need
- A certificate of Spanish tax residency issued by the Agencia Tributaria, specifically the version stating it is issued for the purposes of the UK treaty
- Your NIE
- The completed HMRC form
- Supporting documents such as pension statements or details of the income concerned
The sequence usually runs through the Spanish tax office first, to obtain the residency certificate, and then to HMRC. Getting the right version of the certificate matters: a general residency certificate is not the same document and will be rejected.
When to seek professional advice
Always, and preferably before the move rather than after. Tax rules change, interpretation varies by case, and the cost of advice is small next to the cost of an avoidable filing error. I work with local tax advisers who handle cross-border cases and I introduce clients to them as a matter of course.
Final Thoughts from a Local Property Agent
The UK–Spain treaty is a solid framework and it does what it is meant to do, provided you understand which rule applies to which income. The problems I see are rarely caused by the treaty itself. They come from assuming that one rule covers everything.
My advice is simple: do not wait until tax season to ask the question. The time to work out where your pension, your rental income and your savings will be taxed is before you buy, not after, because the answers can affect what you buy and how you hold it.
I am not a tax adviser. But after years of working with British buyers on this coast, I know which questions to ask, which paperwork to gather and where to send you for the answers. Buying a home abroad should be exciting rather than stressful, and most of the stress comes from unanswered questions.
Looking for Tax-Smart Property Advice?
If you are considering a move or an investment in southern Spain, you can browse my current selection of property for sale in Manilva, or take a look at my area guides for Estepona, Casares, La Duquesa and Sotogrande.
If you would rather talk it through first, get in touch. I will guide you through every step, from the legal checks to the questions worth putting to a tax adviser, so you can buy with confidence.
