When selling shares abroad escapes UK CGT
UK Capital Gains Tax follows your residence status, not where the company or your broker is based. If you are non-resident under the Statutory Residence Test for the whole tax year of the disposal, or the sale falls in the overseas part of a split year, gains on shares are normally outside UK CGT. The exceptions are certain disposals of shares in 'UK property rich' companies (broadly, a 25% or more stake in a company whose value comes mainly from UK land) and direct disposals of UK land and property, which stay within UK tax whatever your status. Our leaving the UK tax guide explains how your residence status and departure date are fixed.
The five-year temporary non-residence trap
This is the trap that undoes most plans. If you were UK resident in at least four of the seven tax years before you left, and your period of non-residence lasts five years or less, gains on shares you owned before departure are treated as arising in the tax year you return and taxed then, at that year's rates with the £3,000 annual exempt amount. HMRC treats 'more than five years' as at least five years and one day, measured using your Statutory Residence Test and split-year dates. Shares you both acquired and sold entirely while non-resident are generally not caught. The full mechanics are in our temporary non-residence guide.
What to do before you sell
Fix your departure and any possible return date under the Statutory Residence Test first, then test the gap against the five-year threshold before crystallising a large gain. If a return within five years is realistic, deferring the sale until you are safely past that mark can avoid the clawback entirely. Your new country will usually tax the gain under its own rules too, so check the local position and any double tax treaty. Selling in the wrong year, or coming home a few months early, can turn a tax-free disposal into a UK bill.