The Double Taxation Convention (DTC) between Andorra and the United Kingdom, signed on 20 February 2025, entered into force on 22 December 2025. The edict was published in the BOPA (Official Gazette of the Principality of Andorra), No. 157/2025, dated 31 December 2025.
This treaty removes the uncertainty that previously affected cross-border transactions between the two jurisdictions by setting out clear rules on: (i) which State taxes which income, (ii) how double taxation is eliminated, and (iii) which anti-abuse safeguards apply.
A. Entry into force vs. effective application
As is often the case in treaty matters, it is important to distinguish between entry into force and effective application (i.e., from when the Convention produces effects for each tax). The Convention sets out these rules in Article 28.
I. Andorra
- Taxes withheld at source: applies to income derived from 1 January 2026.
- Other taxes on income and taxes on capital: applies to tax periods beginning on or after 1 January 2026.
II. United Kingdom
- Taxes withheld at source: applies to amounts paid or credited on or after 1 February 2026.
- Income tax and capital gains tax: applies for tax years beginning on or after 6 April 2026.
- Corporation tax: applies for financial years beginning on or after 1 April 2026.
B. Two important points to keep in mind
I. Arbitration
The arbitration clause (Article 24(5)) will not take effect until the States notify each other, through diplomatic channels, that this provision has entered into force.
II. Exchange of information
Information requests may cover earlier periods (with specific rules for Andorra and without being tied to a particular tax period in the case of the United Kingdom).
I. Andorra
- Cases involving intentional conduct that may be subject to criminal prosecution: requests may relate to tax periods beginning on or after 1 January 2013 (or, where there is no tax period, to taxes arising on or after that date).
- All other cases: requests may relate to tax periods beginning on or after 1 January 2017 (or, where there is no tax period, to taxes arising on or after that date).
II. United Kingdom
- Requests may be made regardless of the tax period to which the matter relates (i.e., without an equivalent time limitation in the provision itself).
C. Key provisions
We invite you to read our analysis of the Convention’s key provisions here.
If you would like to understand how this Convention may affect your investments or income, Carlota Pastora Business Law Firm & Wealth Planning has a team specialised in international taxation to review your specific circumstances, help you define the most efficient strategy, and maximise the treaty’s benefits.
