Break UK residence first
A Greek residence permit changes nothing on its own. You remain within UK tax on your worldwide income until you are non-resident under the Statutory Residence Test, which counts your UK days, work pattern and ties. If you leave part-way through a tax year, split-year treatment can tax you as non-resident from your departure date, and you claim it on the SA109 pages of your Self Assessment return. The P85 is only for leavers who do not need to file a return for the departure year.
What the UK still taxes after you go
Non-residents keep paying UK tax on UK-source income. Rental profits fall under the Non-Resident Landlord Scheme, UK government service pensions stay taxable here, and gains on UK property must be reported and paid within 60 days of completion. Two tails follow you to Greece. Return within five years and the temporary non-residence rules tax gains you realised while away in your year of return. And since 6 April 2025 inheritance tax has been residence-based, so a long-term UK resident, meaning someone resident for 10 of the last 20 tax years, can stay exposed on worldwide assets for up to 10 years after leaving.
What Greece charges instead
Greek residents are taxed on worldwide income at rates running from 9% on the first €10,000 to 44% above €60,000. Two flat regimes soften that for incomers: the Article 5B route taxes foreign pensioners at a flat 7% on all foreign-source income, and the Article 5A non-dom regime fixes foreign income at a €100,000 annual lump sum, each for up to 15 years. Greek-source income is always taxed at normal rates, and the golden visa survives in 2026 at €800,000 in Attica, Thessaloniki and the larger islands, €400,000 elsewhere and €250,000 for conversions and restorations. The full detail, including the unusually thin 1953 treaty, in force since January 1954, is in our Greece guide.