Does a 1031 exchange work if I live in the UK?

It works for US purposes only. Section 1031 defers your US federal gain, but HMRC treats the exchange as a disposal at market value and charges UK capital gains tax immediately. There is no UK rollover relief for investment property. You end up paying UK tax in a year with no US tax to credit against it, which is why many UK-resident Americans avoid exchanges altogether.

Can I claim foreign tax credit relief on a like-kind exchange?

Usually not effectively. Credit relief requires tax in both countries on the same gain in a matchable period. In the exchange year the UK charges tax and the US charges nothing, so there is no US tax to credit. When the US gain is finally recognised years later, the UK charge is smaller because your UK base cost was uplifted, leaving the earlier UK tax stranded.

Is there a UK equivalent of section 1031?

No direct equivalent exists. The UK has business asset rollover relief for replacing assets used in a trade, but property letting and passive investment holdings do not qualify. Section 1031 covers investment real estate generally, which is far wider. Unless your US property is genuinely occupied for the purposes of a trade you carry on, expect no UK deferral at all.

How much UK CGT will I pay on selling US property?

The UK charges capital gains tax on your worldwide gains while UK resident, with different rates for residential property and other assets, and rates depending on your income. Both the rates and the annual exempt amount have changed repeatedly, so check GOV.UK for the current figures. Remember the gain is computed in sterling, so currency movement can significantly increase it.

What happens if I miss the 45-day identification deadline?

The exchange fails for US purposes and the entire gain becomes taxable in that year, including depreciation recapture. The deadline runs from transfer of the relinquished property and cannot be extended for ordinary commercial reasons. Identification must be in writing and delivered to the qualified intermediary. Only limited disaster relief published by the IRS can extend it.

Should I do the exchange before or after moving to the UK?

Before, in almost every case. If you complete the exchange while non-UK resident, or in the overseas part of a split year, the gain generally falls outside the UK charge. Newly arrived residents may also qualify for relief on foreign gains under the UK regime introduced in April 2025. Temporary non-residence rules can undo poorly timed departures, so get advice first.

Section 1031 Exchange and the UK CGT Mismatch Explained

A section 1031 exchange defers United States federal tax on the gain from a like-kind exchange of US real property, but it does not defer United Kingdom capital gains tax. If you are a US citizen or green card holder resident in the UK, HMRC treats the exchange as a disposal for market value consideration on the day it completes, charges CGT for that UK tax year, and offers no equivalent rollover relief for investment real estate. The consequence is blunt: you pay real UK tax in cash at the precise moment there is no US liability to credit it against, and when the US gain finally crystallises years later, the UK tax you already paid is usually stranded. Understanding the mechanics is the only way to avoid converting a deferral into a permanent double charge.

What does section 1031 actually defer after the 2017 tax reform?

Section 1031 of the Internal Revenue Code permits the deferral of gain where property held for productive use in a trade or business, or for investment, is exchanged solely for property of like kind to be held for the same purposes. The Tax Cuts and Jobs Act narrowed this materially. For exchanges completing after the end of 2017, only real property qualifies. Personal property exchanges, business equipment, artwork, aircraft, franchise rights and intangible assets no longer benefit.

Within real property, the like-kind test remains generous. Raw land can be exchanged for an apartment building, a retail centre for an industrial park, a leasehold interest of sufficient duration for a freehold. What matters is the nature of the interest in real property, not its grade, quality or income profile. That flexibility is precisely why US investors use it so heavily, and why the UK problem arises so often.

Does section 1031 apply to non-US property?

No. The Code expressly provides that real property located within the United States and real property located outside the United States are not like-kind. A UK-resident American cannot exchange a Texas apartment block for a London office building and defer the US gain. The relief is a purely domestic US mechanism, which is one reason it interacts so poorly with a foreign residence position.

How do the qualified intermediary and the 45/180-day rules work?

Almost no modern exchange is a simultaneous swap. Instead the taxpayer uses a deferred exchange through a qualified intermediary, relying on the safe harbours in the Treasury regulations under section 1031. The intermediary takes an assignment of the sale contract, receives the proceeds directly, holds them beyond the taxpayer's control, and applies them to acquire the replacement property. If you touch the cash, or have an unrestricted right to receive it, the safe harbour fails and the entire gain is recognised.

Two deadlines govern the timetable, and both run from the date the relinquished property transfers.

You must identify candidate replacement property in writing within 45 days, delivered to the intermediary or another permitted party.
You must receive the replacement property within 180 days, or by the due date of your US return including extensions if that is earlier.
Identification is normally made under the three-property rule, or the 200 per cent rule where more properties are listed.
A fallback 95 per cent rule exists but is unforgiving and rarely relied upon in practice.
Neither deadline can be extended for ordinary commercial difficulty; only limited disaster relief published by the IRS applies.

Reverse exchanges, where the replacement is acquired first through an exchange accommodation titleholder, and improvement exchanges, where construction is completed inside the window, are both possible under IRS safe harbour guidance. They are more expensive and more fragile. Related-party exchanges carry their own restrictions, including a two-year holding requirement, and are a frequent source of disallowance.

Why does the UK tax the exchange when the US does not?

The UK charges capital gains tax by reference to a disposal. A sale in exchange for other property is still a disposal. Under the Taxation of Chargeable Gains Act, where consideration is not wholly in money, the disposal is treated as made for the market value of what is given up, and the acquisition of the replacement is treated as made at market value. HMRC's Capital Gains Manual sets out this approach for exchanges and part-exchanges of land.

Critically, the UK simply does not recognise the US deferral. There is no provision in UK law that imports a foreign rollover. The question HMRC asks is whether a UK relief applies on UK principles, and for investment real estate the answer is almost always no.

Is there a UK equivalent of a like-kind exchange?

There is a rollover relief for replacement of business assets, but it is a much narrower relief than section 1031. It requires that both the old and the new asset are used for the purposes of a trade carried on by the claimant, and that the reinvestment falls within a defined window around the disposal. Land and buildings can qualify, but only where they are trade-occupied assets.

That is the crux. A residential rental portfolio, a triple-net commercial holding, a Delaware statutory trust interest or a passive share of a syndicated deal is investment property, not a trade asset. HMRC will treat property letting as an investment activity in the great majority of cases. Business asset rollover relief therefore does not rescue a typical exchange, and incorporation relief and holdover relief address entirely different transactions.

How is the UK gain computed, and why is it larger than the US gain?

The UK gain is computed in sterling. You convert the acquisition cost at the exchange rate on the date of acquisition and the deemed disposal proceeds at the rate on the date of the exchange. Where sterling has weakened against the dollar over your holding period, a substantial part of the UK gain is pure currency movement that does not exist in the US computation at all.

The base cost differences compound the problem. The US measure of gain reflects adjusted basis reduced by years of depreciation, including cost segregation and bonus depreciation. The UK does not reduce base cost for US depreciation. Meanwhile UK allowable expenditure is confined to acquisition cost, incidental costs of acquisition and disposal, and capital enhancement expenditure still reflected in the asset. Revenue repairs already relieved against rental income are not allowable again.

US gain reflects depreciation recapture, including unrecaptured section 1250 gain taxed at a maximum rate of 25 per cent.
UK gain ignores US depreciation entirely, so the two computations start from different numbers.
Sterling depreciation against the dollar can create a UK gain even where the dollar economics were flat.
Improvement expenditure must be capital in nature and reflected in the property at disposal to be allowable in the UK.
Where UK structures and buildings allowances were claimed on a commercial property, they adjust the UK disposal computation.

What UK CGT rates apply to residential versus other property?

The UK operates different capital gains tax rates for residential property gains and for gains on other chargeable assets, and both sets of rates have been changed more than once in recent years. Residential property gains have historically carried the higher rate. The applicable rate also depends on where the gain sits relative to your income tax basic rate band. Because these rates and the annual exempt amount have moved repeatedly, check the current position on GOV.UK or with your adviser rather than relying on a figure quoted in any article.

Note also what does not apply. The 60-day UK property reporting and payment obligation applies to UK land. A gain on US real property is reported through your self assessment return, on the capital gains and foreign pages, by the ordinary filing deadline.

Why does the timing mismatch destroy foreign tax credit relief?

Double tax relief works only when the same income or gain is taxed by both states in a way the credit rules can match. Under the US-UK income tax treaty, gains on real property situated in the United States may be taxed by the United States, and the UK gives credit for that US tax against its own charge on the same gain. The treaty does not, however, create a credit for tax that has not yet arisen.

In an exchange year, the sequence breaks. The UK charges tax on a gain in, say, the tax year ending 5 April. The US charges nothing, because section 1031 has deferred the gain. There is no US tax to credit. You pay the UK tax in full, out of proceeds that the qualified intermediary is holding and which you are not permitted to access without blowing the exchange.

Years later, when you finally sell the replacement property, the US recognises the deferred gain plus the new gain. By then the UK has already taxed part of that economic gain, and the UK base cost in the replacement property has been uplifted to its market value at the time of the exchange, so the later UK gain is smaller. There is US tax and comparatively little UK tax to credit it against, and no mechanism to carry the earlier UK tax forward.

The net effect over the life of the investment is frequently a permanent excess charge. The UK tax paid early is economically wasted, and the US tax paid late cannot be relieved. In cash flow terms the position is worse still, because the UK bill lands years ahead of the liquidity event that was supposed to fund it.

Does the net investment income tax make this worse?

It can. The 3.8 per cent net investment income tax applies to gains on passive real estate for higher-income US taxpayers. The IRS position is that foreign tax credits under the Code cannot be used to reduce that charge, and litigation on whether treaty relief can achieve a different result has produced mixed outcomes in different treaty contexts. Treat any credit against the net investment income tax as a position to be taken advisedly, not assumed.

How does UK residence status change the analysis?

Everything turns on whether you are UK resident under the Statutory Residence Test in the tax year the exchange completes. If you are not UK resident for that year, a gain on US real property is generally outside the UK charge altogether, subject to the temporary non-residence rules.

Split-year treatment can be decisive. Where you arrive in or leave the UK part way through a tax year and one of the statutory cases applies, the year is divided and gains realised in the overseas part are typically outside the UK charge. Completing an exchange in the overseas part of a split year is one of the cleanest solutions available, but the case conditions are technical and the day counting is unforgiving.

The temporary non-residence rule then patrols the exit. If you leave the UK, realise gains, and return within the statutory period, gains on assets you held before departure can be pulled back into charge in the year of return. Short-term departures rarely solve the problem.

Can newly arrived UK residents avoid the charge?

Possibly. From 6 April 2025 the UK replaced the remittance basis with a residence-based regime giving qualifying new arrivals relief on foreign income and gains for a limited initial period, where they have been non-UK resident for a sufficiently long preceding period. A US real property gain is a foreign gain for these purposes. If you are inside that window and you make a valid claim, the exchange may fall outside the UK charge entirely.

The regime carries conditions and trade-offs, including the loss of certain UK allowances in a claim year and detailed reporting. Former remittance basis users may also have access to transitional rebasing and repatriation measures. HMRC's published guidance on the foreign income and gains regime is the starting point, and this is an area where the detail moves.

What planning actually works?

There is no elegant fix that makes the UK follow the US deferral. Realistic planning is about sequencing, structure and honest arithmetic.

Model the after-tax outcome of an outright sale against an exchange before instructing anyone. Frequently the exchange is worse.
Where an exchange is commercially necessary, align it with a year of non-UK residence or the overseas part of a split year.
Consider whether the UK charge is affordable from other liquidity, because exchange proceeds are locked with the intermediary.
Test whether the property is genuinely trade-occupied, in which case UK business asset rollover relief may be available.
Where a US gain will eventually be recognised, consider matching it with a UK disposal so credit relief has something to work on.
Review whether holding the asset until death, with the US basis step-up, produces a better lifetime result than serial exchanging.

Do holding structures solve it?

Sometimes, at a cost. Holding US real estate through a US corporation moves the disposal inside the company, so an asset sale does not create a personal UK disposal for the shareholder. The price is US corporate tax on the gain, potential double taxation on extraction, and possible UK anti-avoidance exposure. For a UK-resident shareholder, close company and attribution rules must be considered carefully.

Partnerships and LLCs raise a separate problem. HMRC generally treats a US limited liability company as opaque, while the US treats it as transparent by default. The Supreme Court decision in Anson showed that the characterisation question is fact-sensitive, but HMRC's stated practice remains restrictive. A mismatch here can mean the UK sees a distribution taxed as income while the US sees a capital gain, further breaking credit relief. Delaware statutory trust interests used as replacement property raise the same classification risk.

What are the most common mistakes?

Assuming the UK follows the US deferral because the transaction is described as a swap rather than a sale.
Completing an exchange without reserving cash for a UK tax bill that cannot be funded from the intermediary's account.
Treating a buy-to-let or triple-net portfolio as a trade asset and claiming UK rollover relief that does not apply.
Overlooking sterling currency movement, which can turn a modest dollar gain into a substantial UK charge.
Failing to record UK market value at the exchange date, leaving the replacement property's UK base cost unevidenced.
Missing the 45-day identification deadline because of UK-side delays, which collapses the US deferral and creates a full US charge.
Ignoring US state tax, including clawback regimes that track deferred gain when property leaves the state.
Receiving boot, including relief from mortgage debt, and not recognising it as taxable in the US while the UK taxes the whole gain regardless.
Reporting the exchange on the US return but omitting it from UK self assessment because no cash was received.
Relying on a treaty credit in a year where the other country has charged nothing.

What records should you keep?

Cross-border exchanges are audited on documentation, and the UK record is usually the weaker one because the transaction was designed by US advisers. Build the UK file at the time, not years later when the replacement property is sold.

The exchange agreement, assignment documents and the qualified intermediary's account statements and settlement ledgers.
The written 45-day identification notice and evidence of the date it was delivered.
Closing statements for both the relinquished and the replacement property, with all costs itemised.
An independent market valuation of both properties at the exchange date, supporting the UK deemed consideration and new base cost.
The exchange rates used for acquisition and disposal, with the source and date recorded.
A full capital expenditure history, with invoices distinguishing capital enhancement from revenue repairs.
Copies of the US return and Form 8824 for the exchange year, and the UK return pages reporting the same event.
A standing schedule reconciling US adjusted basis to UK allowable cost, carried forward for the life of the holding.
Residence evidence for the exchange year, including day counts and split-year case analysis where relevant.

Where should you look for authoritative guidance?

On the US side, the IRS instructions to Form 8824 and the like-kind exchange material on IRS.gov set out the mechanics and the reporting, and IRS Publication 519 remains the reference point for residence and source questions. On the UK side, HMRC's Capital Gains Manual covers disposals for non-cash consideration and market value, and HMRC's Double Taxation Relief Manual addresses credit relief. The US-UK income tax treaty governs which state may tax the gain and how relief is given.

What is the practical conclusion?

For a US person living in the UK, a section 1031 exchange is usually a tax deferral for one country purchased with an accelerated tax charge in the other. That trade is rarely worth making unless the UK charge can be removed by residence timing, the asset genuinely qualifies for UK rollover relief, or the commercial case for the replacement property is compelling enough to absorb the cost. Decide before you sign, because once the intermediary holds the proceeds your options narrow sharply.

This article is general commentary on US and UK tax principles and is not advice. Rates, thresholds, residence rules and the UK regime for foreign income and gains change frequently, and the outcome in any particular case depends on your residence position, the nature of the property, the structure through which it is held and the terms of the exchange. Before entering into or unwinding any like-kind exchange, take specific advice from advisers qualified in both jurisdictions who can review your facts together.