United Kingdom and Spain · Relocation guide
British and Spanish citizenship: declaration, renunciation and retention
The UK permits dual citizenship, but a British applicant acquiring Spanish nationality by residence normally faces Spain’s article 23 declaration. That is not itself formal renunciation of British citizenship to the UK.
Content updated 11 September 2026. Individual source-check dates are listed below.
Apply both laws to the exact acquisition route
GOV.UK permits dual citizenship and has no separate dual-status application. Spain decides the declaration required to acquire Spanish nationality and the later rules for retaining it. Record acquisition route, existing nationality, residence, birthplace and whether Spanish nationality is by origin.
Nationality approval, Civil Registry completion and passport issue are separate milestones. A residence card is not citizenship.
Do not merge three different legal acts
Civil Code article 23 requires an adult acquiring nationality by option, residence or carta de naturaleza to swear or promise allegiance, declare renunciation of the previous nationality subject to listed exceptions, and register acquisition. British nationality is not among the named exceptions.
That Spanish declaration does not itself complete the UK’s formal renunciation procedure. Article 24 separately contains loss and retention rules for specified Spaniards habitually abroad, including a three-year retention declaration in defined cases. Article 25 addresses loss for Spaniards not Spanish by origin, including specified exclusive use of a nationality declared renounced.
Name the act before taking it
Use the Civil Registry or consulate for the paragraph applying to your facts. Keep the Spanish decision, oath, declaration and registration record separately from British citizenship evidence.
| Act | Authority | Meaning |
|---|---|---|
| Article 23 declaration | Spanish Civil Registry | Acquisition requirement |
| Formal British renunciation | UK authority | Separate loss process |
| Article 24 retention | Spanish Civil Registry or consulate | Only where that paragraph applies |
| Passport use | Border authority | Travel evidence, not tax residence |
Build the Spanish acquisition file in sequence
For nationality by residence, follow the Ministry of Justice process and identify the residence period and evidence applying to the applicant. Keep residence cards, registrations, passports and absences in a chronology; merely reaching an anniversary does not prove approval.
After a favourable decision, complete the Civil Registry formalities in the required window. Preserve the oath or promise, renunciation declaration and registration record, and ask which civil documents and translations remain current.
Separate citizenship, passports and residence consequences
Use the passport or proof required by each border. A Spanish residence card is not Spanish nationality, and a Spanish acquisition declaration is not proof that the United Kingdom accepted formal renunciation of British citizenship.
Marriage and parentage can create different routes but do not make every spouse or child follow the same result. Check each person’s birthplace, parentage, acquisition route and registration. Tax residence, healthcare and voting require separate analysis.
Your moving checklist
Tick off the tasks that apply to you. The timing is a planning order, not a substitute for the deadlines on your permission or an official instruction.
0 of 7 tasks completed
Sources and checks
The linked authorities set the rules. VisaAtlas explains how the steps fit together; planning suggestions are not a decision on your immigration status, tax residence or entitlement to services.
- GOV.UK: dual citizenshipSource checked 11 September 2026
- Spanish Ministry of Justice: nationality by residenceSource checked 11 September 2026
- BOE: Spanish Civil Code, articles 23 to 25Source checked 11 September 2026