If you're moving to the UK with unvested RSUs already granted, the question isn't really "how are RSUs taxed in the UK" — it's whether anything changes because some of that grant-to-vest period happened before you were ever UK resident. It can, but only if you know to ask.
The baseline: vesting is still the taxable event
Nothing about UK residence changes the basic mechanics. RSUs are taxed as employment income at the point they vest, valued at the market price on that date — the same treatment as salary landing in your account. Sell the shares later at a different price, and any further movement is a capital gains question, separate from the income tax already paid at vest.
Once you're UK resident, the full value of a vesting tranche is, by default, taxable here — regardless of where the company that granted it is listed, and regardless of how much of the vesting period happened before you arrived.
Where the grant date actually matters
That "by default" is doing a lot of work. If you meet the FIG regime's qualifying new resident test — broadly, 10 consecutive tax years of non-UK residence before you arrived — Overseas Workday Relief can exempt part of a tranche's value, and the period that matters for that isn't the vest date at all. It's the tranche's own grant-to-vest window.
A tranche vesting six months after you land in the UK might have been granted three years earlier — meaning most of its sourcing window was spent entirely overseas, well before you had any UK tax presence at all. The overseas fraction of that specific window is what determines how much of the tranche can be exempt, not the fraction of your calendar year that was overseas. See how OWR is actually calculated for RSUs for the detail on why this needs tranche-by-tranche treatment rather than a single number.
The part people usually get wrong
Two mistakes show up constantly:
- Treating the vest date's tax year as the only relevant period, when the sourcing period is the grant-to-vest window — which can span several tax years and start well before UK arrival.
- Assuming currency conversion uses a single "official" rate, when RSU values are normally best taken at the GBP figure your employer's payroll already used, since that's what will reconcile with your payslip and P60.
Where FIG Tracker fits in
FIG Tracker sources every RSU tranche individually over its actual grant-to-vest window and works out the overseas fraction from real workdays in that period, rather than a single blended number for the tax year. If you also have equity from before you were even offered a UK role, see what changes (and doesn't) depending on where you moved from.
FIG Tracker is a calculation aid, not tax advice. Always verify your eligibility and figures with a qualified tax advisor before filing with HMRC.