Selling Your Startup After Leaving the UK: The 5-Year Temporary Non-Residence CGT Trap (2026)

You leave the UK, become non-resident, sell your company in a year when the tax rate where you now live is far lower, then move back a couple of years later. The capital gains tax you thought you had stepped around does not disappear. Under the UK's temporary non-residence rule, gains you realise while abroad can be pulled back into charge and taxed in the tax year you resume UK residence, as if they accrued then.

The rule bites where two things are true: 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 fewer. Two things make 2026 a worse year to get this wrong: the carve-out that sheltered dividends taken while abroad is gone from 6 April 2026 and the dividend rates went up on the same day, and the deadline for claiming Business Asset Disposal Relief can expire before the deferred charge lands.

This article explains how the trap is built, which gains it catches, and what a genuine departure requires. It is general information about how the rules work in 2026, not tax advice; a sale of this size needs a UK tax adviser looking at your own dates.

What the temporary non-residence rule actually does

The rule lives in the Taxation of Chargeable Gains Act 1992, at section 10A, and was rewritten to sit on the Statutory Residence Test by Finance Act 2013, Schedule 45, Part 4, for people who left the UK from the 2013/14 tax year onward. Its job is narrow and deliberate: to stop someone stepping outside UK residence for a short spell purely to realise a large gain at a lower rate, then stepping back in.

Here is the mechanism. If you are non-resident for a period that turns out to be temporary, certain gains you make during it are not taxed while you are away. Instead they are treated as accruing in the tax year you resume UK residence, the "year of return", and taxed then. The gain does not vanish because you were non-resident when you signed the share purchase agreement. It waits, and reattaches the moment you come back inside the window.

That single design choice is what catches founders off guard. The common mental model is "I was non-resident on completion day, so no UK CGT." The rule's answer is that completion day is not the test; what matters is whether your absence lasted long enough to count as permanent.

The two conditions that spring the trap

Two tests have to be met before the charge applies. Miss either and the rule does not bite.

• Condition one, your residence history. You must have been UK resident, in the sense the legislation uses of "sole UK residence", for at least four of the seven tax years immediately before the tax year you departed. This is the "you were really a UK person" test. A founder who built and ran a company from the UK for years before leaving will almost always satisfy it. Someone who was only briefly UK resident may not, and that person sits outside the rule however short the absence. One detail founders miss: split years count here too, not just at the far end of the absence. Where a tax year is split, sole UK residence for the UK part of it is enough to make that year one of the four, so a year you think of as half in and half out can still push you over the threshold.
• Condition two, the length of your absence. Your period of non-residence has to be five years or fewer. Come back inside that window and you are temporarily non-resident, so the rule applies. Stay out longer and it falls away. Under the post-2013 framework the five years is measured between residence periods defined by the Statutory Residence Test, not by counting whole tax years, and split-year treatment can move the boundaries, which is why "roughly five years" hides real complexity in individual cases.

Put dates on it and the complexity becomes obvious. Say you were UK resident throughout 2026/27 and leave on 1 October 2027. Your period of non-residence starts when your sole UK residence ends inside that split year, not on the following 6 April. You sell the company in 2028/29 while abroad. Come home on 1 September 2032 and the absence is four years and eleven months, so the rule applies and the whole gain is charged in 2032/33. Come home on 1 December 2032 instead and the absence is five years and two months, so it does not. Three months of diary decide a seven-figure bill. HMRC works through the permutations in its own examples at CG26565 to CG26568, and they are worth reading before anyone books a flight.

The practical takeaway is blunt: a one-year or two-year exit to crystallise a sale is exactly the fact pattern the rule was written for. It is not a loophole the legislation overlooked; it is the thing the legislation targets.

Which gains get caught, and which slip through

Not every gain you make abroad is in scope. What matters most for a founder is when you acquired the asset.

Broadly, the rule reaches gains on assets you held before the year you left the UK. Your founder shares, acquired at incorporation or in an early round, are the textbook case: held before departure, sold while abroad, charged on return.

Assets you both acquire and dispose of entirely within your non-resident period generally fall outside the charge. If you leave, then start and sell a brand new venture while you are away, that new gain is usually not caught, though anti-avoidance provisions target arrangements designed to exploit this line, so it is not a free pass. The boundary sits on acquisition and disposal dates, which is exactly where confident planning turns into a wrong assumption: anyone relying on the "bought and sold while abroad" carve-out should have the dates checked against the statute first.

It is also worth knowing the rule is not CGT-only. The same Part 4 framework reaches income a departing owner-manager might reach for, including distributions and dividends from close companies under sections 401C, 408A and 413A of ITTOIA 2005 and section 812A of ITA 2007, and certain pension withdrawals taken during the absence.

That part of the rule got materially harder in 2026, and it is the change most likely to catch a founder mid-plan. There used to be a carve-out for "post-departure trade profits": dividends traceable to profits the company earned after you left escaped the charge, with the split made on a just and reasonable basis. Announced at the Autumn Budget 2025 and legislated in Finance Act 2026 (c. 11), section 43 and Schedule 3, paragraph 19, that carve-out is abolished. Plainly stated: for anyone resuming UK residence on or after 6 April 2026, every dividend or distribution received from a UK close company during the temporary non-residence window is chargeable to UK income tax in the year of return, whenever the underlying profits arose.

The rates moved on the same date, which doubles the effect. From 6 April 2026 the dividend ordinary rate rose from 8.75% to 10.75% and the dividend upper rate from 33.75% to 35.75%; the additional rate is unchanged at 39.35%. Because the charge falls in the year of return, a founder coming back on or after 6 April 2026 meets the new rates applied to the whole distribution, with nothing carved out. If the plan was to leave, then draw the company's profits out as dividends while non-resident, it has lost its last piece of shelter and got more expensive at the same time. Foreign tax paid on the same distribution can still be credited, but a credit is not an exemption.

The same paragraph of Schedule 3 also shuts the obvious workaround. It inserts subsection 401C(6A) into ITTOIA 2005: where a company makes a payment to a temporarily non-resident individual, that individual is a material participator in another company that controls the payer, and the payment appears designed to avoid a relevant distribution, the payer is deemed to make a relevant distribution. Routing the money out through a second company you control does not put it beyond the charge.

Whether running your UK company from an EU country creates a separate residence or permanent-establishment problem is a different issue, covered in our guide to running a UK Ltd company while resident in Spain, Portugal or France.

The year the bill lands: charged on return, not on sale

One feature of the rule causes more nasty surprises than any other: the timing. The gain is not charged in the tax year you sold; it is charged in the tax year you resume UK residence. Leave in 2026, sell in 2027 while abroad, move back in 2029, and the CGT does not appear on a 2027 return. It appears on the return for the year you came home, two or three years after the money hit your account.

That gap is dangerous in a specific way. By then the cash is long gone into a house, a new company, or another investment, and a UK self-assessment liability for the whole historic gain materialises anyway. Plan for the timing as carefully as for the rate, because the two are separate problems.

Where the FIG regime and the non-dom changes fit

The UK's non-dom landscape changed substantially on 6 April 2025. The remittance basis was abolished and replaced by the Foreign Income and Gains regime, and domicile stopped being the connecting factor for income tax and capital gains tax on income and gains arising from that date. Domicile has not vanished from the tax code: it survives in the transitional rules and in matters arising before that date. In place of the old system, "qualifying new residents", broadly those in their first four years of UK residence after at least ten consecutive tax years of non-UK residence, can claim relief on foreign income and gains for those four years.

It is tempting to read that as a rewrite that swept the old anti-avoidance rules away. It did not. The temporary non-residence rule still sits in the legislation, doing the same job. The FIG regime governs relief for people arriving in the UK; the temporary non-residence rule governs people who leave and come back.

Be precise about how little the two overlap, because founders often assume FIG is somehow an answer to the exit problem. The clocks point in opposite directions. Temporary non-residence bites on absences of five years or fewer; FIG's qualifying new resident status needs at least ten consecutive tax years of non-UK residence before you arrive. One departure cannot normally satisfy both. Leave for two or three years and you are squarely temporarily non-resident with no FIG in sight; stay away long enough to open the FIG door and the rule can no longer reach you. Both can appear in one long life story, but they are not two levers on the same move.

If you are moving to the EU rather than staying in a zero-tax hub, the treaty position adds another layer. The UK's treaty network allocates taxing rights between countries and can change where a gain is ultimately taxed. The new UK to Portugal double tax convention is the current example: signed in London on 15 September 2025, in force from 29 December 2025, and effective for UK income tax and capital gains tax from 6 April 2026. We unpack what it changes for founders in our guide to the UK to Portugal tax treaty. It is another reason not to treat the exit as a single-country calculation.

Thinking about where to land, not just how to leave? A short call with Relovisa's France Talent team maps the founder-visa side of the move so the immigration plan and the tax plan are built together.

BADR, the 24% rate, and why patience is the real plan

Rates set the size of the bill the rule can revive. Since 30 October 2024 the main higher rate of UK capital gains tax has been 24%, and the Autumn Budget 2025 and the March 2026 Spring Statement both left it there, so 24% is still the number for 2026/27. Business Asset Disposal Relief, the former Entrepreneurs' Relief that gives founders a reduced rate on qualifying business disposals, has been climbing on a set schedule:

• 10% until 5 April 2025
• 14% for disposals on or after 6 April 2025
• 18% for disposals on or after 6 April 2026
• £1 million lifetime limit on qualifying gains, frozen since 11 March 2020

On a large exit only the first slice benefits from the reduced rate, and the balance is exposed to the main 24% rate. The annual exempt amount is £3,000 for 2026/27, which on a founder exit is a rounding error rather than a plan.

Before worrying about rates, check the relief is available at all. BADR on a share sale needs the company to be your personal company, meaning you hold at least 5% of the ordinary share capital and voting rights, needs you to be an officer or employee of it, and needs both to have been true throughout the two years ending on the date of disposal. A founder who resigned from the board to make the departure look clean, or who was diluted below 5% in a pre-sale round, can fail those conditions before the temporary non-residence rule ever comes up. HMRC's helpsheet HS275 sets out the tests. One more availability point for anyone weighing an employee ownership trust against a trade sale: for disposals from 26 November 2025 the relief on a qualifying disposal to an EOT is cut from 100% to 50% of the gain, and BADR and Investors' Relief cannot be claimed on that gain at all. The remaining half is still held over and deducted from the trustees' acquisition cost. You pick one route, not both, and the EOT route is worth materially less than it was.

If you are tempted to beat a rate rise by signing early, anti-forestalling rules sit alongside each increase, and they are not discretionary. Where an unconditional contract is made before a rate change but completes after it, the later rate applies automatically. To get the earlier rate the parties have to make a claim, and to win it they must show the contract was not entered into to obtain that timing advantage and, where the parties are connected, that it was entered into wholly for commercial reasons. There is one relief valve: no claim is needed where the total gains on all such contracts come to £100,000 or less. Above that, a contract signed in March to lock in 14% is exactly the pattern the provisions are written to test, and the burden of proof sits with you.

The BADR claim deadline that expires before the bill arrives

Here is the trap inside the trap, and it undercuts any plan built on the relief still being there when the charge lands. A BADR claim must be made on or before the first anniversary of the 31 January following the tax year in which the qualifying disposal is made. That deadline runs from the year of disposal. The temporary non-residence rule moves the charge to the year of return. Those are different years, and on a typical founder timeline the claim window closes first: sell in 2027/28 and the claim deadline is 31 January 2030, but return in 2030/31 and the gain becomes chargeable in a year for which the relief can no longer be claimed in the ordinary way.

Specialists treat a protective BADR claim, made at the time of disposal even though no charge has yet arisen, as the defensive move. It is not a solved problem: the interaction of the deeming provision with the claim time limit is unclear, and firms writing on it say a protective claim may be possible but there is no guarantee it will be effective. The conclusion for a founder: do not assume the relief will be waiting. If you are selling business assets while non-resident with any prospect of returning inside the window, decide the claim question before completion.

Put those numbers next to the temporary non-residence rule and the strategic point is clear. Becoming non-resident for a year does not, on its own, turn a UK-taxable founder exit into an untaxed one: return inside the window and the UK rate you were trying to avoid is the rate you pay, just later, and possibly without the relief you were counting on. The only version of "leave to sell" that reliably works on the UK side is the one where you do not come back inside the five-year window, which is a life decision about where you want to live, not a timing trick. The middle path, a brief tactical absence, is the one the rule is built to close.

Double tax relief and the zero-tax-jurisdiction problem

A reasonable question is whether foreign tax paid on the sale offsets the UK charge. In principle, where you pay tax in another country on the same income or gain, double tax relief or a treaty credit can reduce the UK liability, so you are not taxed twice on the same money.

Be precise about what that relief is. HMRC's guidance on temporary non-residence spells the mechanism out for distributions: foreign tax paid on the income while you were temporarily non-resident can be offset against the UK liability that arises in the year of return. That is credit relief, and credit is not exemption. Whether a particular treaty does more than that on capital gains, and actually stops the UK raising the return-year charge rather than merely crediting foreign tax against it, turns on the wording of that specific convention and on where you were resident when the gain accrued. It is a question for an adviser holding the treaty text, not something to assume in either direction.

The problem is that the departures most tempted by a quick exit tend to be to places with little or no capital gains tax, a Gulf hub being the obvious example. Realise the gain somewhere with 0% CGT and there is no foreign tax to credit, so when the rule reattaches the gain on your return the full UK amount is payable with nothing to set against it. The very feature that made the destination attractive, no local tax, is what leaves the revived UK bill undiluted. If your destination does tax the gain the credit position is better, but also more technical, and it belongs in an adviser's hands.

If the plan is to leave and build again

Many founders selling up are not chasing a tax window at all. They want to take the exit and build the next thing somewhere new, and the UK's rising CGT and BADR rates are one more reason the EU is on the table. If that is you, the rule reframes the decision: a half-hearted, come-back-soon departure is the worst of both worlds, while a committed long-term move is both what escapes the rule and what a founder route is designed to support. Still weighing whether to stay and build under the UK's own founder route? Our UK Innovator Founder visa versus EU Startup Visa comparison sets the stay-and-build option next to the leave-and-build routes below.

Two destinations fit a founder who wants to keep building. France's Talent route, the porteur de projet strand often called the French Tech Visa, is aimed at founders bringing an innovative project: see our French Tech Visa for founders guide. Spain's Startup Visa, approved through ENISA under the Startup Act, targets scalable, innovative ventures, and our Spain Startup Visa guide walks through the approval criteria. Weighing the two? Our France Talent versus Spain Startup comparison sets them side by side.

The tax side of the destination matters as much as the visa. Where you become resident determines how your future income and later gains are taxed, and both countries have regimes built to attract incoming founders: Spain's Beckham Law, a flat 24% for qualifying new arrivals that treats all employment income as obtained in Spain, covered for a British founder specifically in the Beckham Law for British founders, and Portugal's IFICI, the successor to the old non-habitual resident regime. Our comparison of IFICI versus the Beckham Law explains the trade-off, and our founder exit tax guide covers what a founder actually pays on exit across France, Spain and Portugal. Since all of this turns on where you are tax resident, and residence is not the simple day-count many founders assume, read how the 183-day rule really works and compare the all-in cost of the main EU founder visas before you commit.

Sequencing is the thing to get right. The exit charge, the destination visa and the landing-country tax regime are three decisions that interact, and taking them in the wrong order, or treating the move as a UK-only tax question, is how founders end up with a residence permit in one country and an avoidable tax bill in another.

Planning to sell up and build again in Europe? Talk to Relovisa about the France Talent route so the visa timeline and the exit timeline line up from the start, not after the fact.

Frequently asked questions

How long do I have to be non-resident to avoid UK CGT on selling my company? The charge only exists where two conditions are both met: your absence is five years or fewer, and you were UK resident in at least four of the seven tax years before you left. They are cumulative, so failing either one defeats the charge, and someone without that four-of-seven UK history is outside the rule however short the absence. For a founder who ran a UK company for years, that history is a given, so the length of the absence is the live question. It is measured between residence periods defined by the Statutory Residence Test, not by counting whole tax years, so confirm your own dates with a UK tax adviser.

Does the rule apply if I bought the shares after I left? Generally it targets assets held before the year of departure. Assets both acquired and disposed of during the absence usually fall outside the charge, subject to anti-avoidance rules, so get the dates checked before relying on it.

Which tax year is the gain charged in? The tax year you resume UK residence, not the year you sold, so the bill can arrive years after the disposal.

Can I take dividends out of my UK company while non-resident? From 6 April 2026, not without a bill on return. Finance Act 2026 (c. 11), section 43 and Schedule 3, paragraph 19 abolishes the post-departure trade profits carve-out, so for anyone resuming UK residence on or after that date all close-company distributions received during the window are chargeable in the year of return. The rates went up the same day: dividend ordinary rate 10.75%, up from 8.75%, upper rate 35.75%, up from 33.75%, additional rate unchanged at 39.35%. The same schedule deems a distribution where the payment is routed through a company you control to dodge the charge. Foreign tax paid can be credited against the UK liability, but the charge stands.

Did the 2025 non-dom and FIG changes remove this rule? No. The Foreign Income and Gains regime replaced the remittance basis from 6 April 2025 and removed domicile as the connecting factor for income tax and CGT on income and gains arising from then, but the temporary non-residence anti-avoidance rule remains in the legislation. The two rarely touch the same departure: five years or fewer for temporary non-residence, ten or more prior non-resident years for FIG.

If I am leaving for good anyway, does it matter? Much less. The rule targets short, temporary departures; a genuine long-term move is the situation it is designed not to catch.