US UK Accountants: Selling a UK Dental or Medical Practice

An American dentist, GP partner, consultant or veterinary principal who sells a UK practice files two very different returns for the same deal. HMRC taxes the sale mainly as a capital gain, often at the Business Asset Disposal Relief rate. The IRS breaks it into its separate assets, taxes equipment recapture as ordinary income and gives no BADR equivalent, so UK tax may not cover the whole US bill.

For the specialist US UK accountants who prepare these returns, a practice sale is one of the most technical events a US citizen in Britain can report. The sale agreement is written for HMRC. It rarely says anything about what the US return needs, and the two systems split the proceeds in different ways. This guide covers what both sale-year returns contain, where the mismatches come from and which elections and claims have deadlines. It is written for practitioners selling a dental, medical, private consulting or veterinary practice, often to a corporate group, and for the professionals advising them. It does not cover tech-founder exits or ongoing private practice income. It is about the year you sell.

Why is a UK practice sale taxed so differently by HMRC and the IRS?

The UK looks at what you sold as a whole. If you trade as a sole trader or partner, the goodwill, and any premises you own, are chargeable assets for capital gains tax. Equipment you claimed capital allowances on is dealt with through a balancing adjustment in your income tax computation. If you own a practice company, you sell shares, and the company's assets do not appear on your personal UK return at all.

The US system is harder on sellers in three ways. First, it has no Business Asset Disposal Relief. Your long-term capital gain is taxed at the ordinary US capital gains rates, whatever the size of the UK relief. Second, it applies asset-by-asset treatment. An asset sale, or the sale of an interest in a partnership that is transparent for US purposes, is split into goodwill, equipment, premises and receivables, and each class has its own character. Third, US rules recapture past depreciation and amortisation as ordinary income, and that can include amortisation of goodwill you originally bought.

The result is predictable. The UK may tax much of the gain at a reduced rate, while the US taxes some of it at full ordinary rates and the rest at up to 20% plus, in some cases, the 3.8% Net Investment Income Tax. Whether the foreign tax credit clears the US liability depends on the rate gap, how the gain is sourced, which basket it falls into and when each country taxes it.

What UK tax is due when you sell a dental or medical practice?

Capital Gains Tax and Business Asset Disposal Relief

A UK-resident individual pays capital gains tax on the gain from goodwill, premises and, on a company sale, shares. The main CGT rates for gains above the basic-rate band have been 24% since 30 October 2024. Business Asset Disposal Relief reduces the rate on qualifying gains up to a lifetime limit of £1 million. The BADR rate was 10% for disposals before 6 April 2025, 14% for disposals from 6 April 2025 to 5 April 2026, and it is 18% for disposals on or after 6 April 2026. HMRC has anti-forestalling rules on contracts exchanged before a rate change and completed afterwards, set out in its Capital Gains Manual at CG64174. The contract date and the completion date both matter, and both belong in your file.

For a sole trader or partner, the qualifying conditions generally require you to have owned the business, or your partnership interest, for at least two years up to the disposal. For a share sale of a practice company, you generally need at least 5% of the ordinary share capital and voting rights, plus a 5% economic entitlement, and you must be an officer or employee throughout the two years before the sale. Premises held personally and let to your own practice company may qualify as an "associated disposal" only in restricted circumstances, and rent charged in the past can reduce the relief.

Goodwill, equipment and premises: allocation matters twice

The purchase agreement should allocate the price between goodwill, fixtures and equipment, stock and any premises. In the UK, the amount allocated to equipment that has been pooled for capital allowances goes into the pool as disposal value. If you took Annual Investment Allowance on dental chairs, imaging equipment or practice-management systems, a large allocation can produce a balancing charge. That charge is taxed as trading income at your marginal rate, not as a capital gain. Buyers usually prefer a high allocation to plant because it gives them allowances, so the seller should negotiate this point rather than accept the buyer's figure.

The same allocation is then used in the US calculation, but US basis is rarely the same as UK tax written-down value. Property used predominantly outside the United States must generally be depreciated under the US Alternative Depreciation System, which is slower than UK AIA. So US adjusted basis on your equipment is often higher than the UK tax written-down value, and the US recapture can differ from the UK balancing charge in amount and sometimes in direction.

NHS contracts and the goodwill question

NHS dental contracts can often transfer with the practice, subject to commissioner consent. Rules restricting the sale of goodwill in NHS general medical practices mean that a GP partner's disposal is usually of premises, private work and partnership capital, not NHS goodwill. The contract terms determine what can actually be sold. They also determine what both returns can properly describe as goodwill.

Earn-outs and deferred consideration

Sales to corporate groups often pay part of the price later: a fixed deferred sum, a retention, or an earn-out linked to future practice profits. For UK purposes, fixed deferred consideration is generally taxed in the year of disposal with no discount for the delay, although tax on instalments paid over more than 18 months can sometimes be paid in instalments. An unascertainable earn-out is treated as a separate asset (the Marren v Ingles principle). Its value at completion forms part of your disposal proceeds, and later receipts are a separate disposal of that right, which may not qualify for BADR. Where the earn-out is paid in shares or loan notes of the buyer, different share-for-share rules can apply. The structure chosen at heads of terms decides which regime applies.

Retained employment: consideration or income?

Most corporate buyers need the selling principal to stay on as an associate, clinical director or consultant for a period. If part of the price depends on you continuing to work, not only on the practice's performance, HMRC may treat that part as employment income taxed at up to 45% plus National Insurance, not as capital. Leaver clauses that reduce deferred consideration if you resign early are the classic warning sign. Restrictive covenants given in an employment context can also be taxed as earnings. The drafting of the SPA and the service agreement together determines where this line falls, and the US return has to follow a consistent position.

How does the IRS tax the sale of a UK practice?

Asset sale or partnership interest: asset-by-asset

If you practise as a sole trader, the IRS treats the sale as a sale of each asset separately. Where goodwill is involved, both buyer and seller must allocate the price under the residual method on Form 8594, Asset Acquisition Statement. A UK buyer will never file a Form 8594, but you still must. This is a common omission when practitioners use a non-US preparer in the sale year.

• Self-created goodwill usually has a zero basis and gives long-term capital gain, taxed at up to 20%.
• Purchased goodwill that you amortised under section 197 is section 1245 property to the extent of amortisation taken. That part of the gain is ordinary income.
• Equipment and fixtures produce section 1245 depreciation recapture, taxed as ordinary income at up to 37%, reported on Form 4797.
• Premises produce capital gain, with any straight-line depreciation taxed as "unrecaptured section 1250 gain" at up to 25%.
• Receivables and work in progress are ordinary income.

A partner in a UK partnership or LLP is usually treated as a partner in a foreign partnership for US purposes. The sale of that interest is a capital transaction, but section 751 recharacterises the share of "hot assets", including unrealised receivables and potential section 1245 recapture, as ordinary income. IRS Publication 544 sets out the general rules for business dispositions and recapture.

Share sale of a practice company: the hidden US traps

A share sale is often best in the UK because BADR applies to the whole qualifying gain and the buyer takes on the company's history. For a US shareholder, three questions decide what the IRS sees:

• Has the company elected to be disregarded? Some US-owned UK practice companies filed a check-the-box election (Form 8832). If so, the IRS treats a UK share sale as an asset sale, with full section 1245 recapture, while HMRC sees a share disposal with BADR. This is the widest mismatch there is.
• Is it a controlled foreign corporation? A company owned more than 50% by US shareholders is a CFC. Under section 1248, gain on the sale of CFC shares by a 10% US shareholder can be recharacterised as a dividend to the extent of the company's untaxed earnings and profits. Earnings already taxed under the GILTI regime (now called net CFC tested income) or subpart F are excluded. A dividend from a UK company can still qualify for the capital gains rates under the US-UK treaty, but the character, source and FTC basket can all change.
• Is NIIT due? Gain on shares in a foreign corporation is generally net investment income. The exception for active trades mainly applies to interests in pass-through entities.

The final Form 5471 for the year of sale must also be filed, reporting the disposal. If earlier Forms 5471 were missed, penalties can start at $10,000 per form per year, and they should be dealt with before the sale-year return draws attention to the company.

US vs UK treatment at a glance

Element of the sale	UK (HMRC)	US (IRS)
Self-created goodwill	CGT; BADR 18% on first £1m of lifetime qualifying gains, 24% above	Long-term capital gain, up to 20% (+3.8% NIIT where it applies)
Purchased goodwill previously amortised	CGT on the gain over cost	Section 1245 recapture of amortisation as ordinary income, up to 37%
Equipment, chairs, imaging	Capital allowances balancing charge taxed as trading income	Section 1245 recapture as ordinary income; ADS basis usually differs
Premises	CGT; BADR only where the conditions are met	Capital gain; unrecaptured section 1250 gain up to 25%
Shares in a practice company	CGT with BADR if conditions are met	Capital gain, possible section 1248 dividend; asset sale if disregarded
Earn-out	Value taxed at completion; later receipts a separate disposal	Often the installment method; recapture taxed in year of sale
Employment-linked consideration	Employment income, up to 45% + NIC	Wages; the foreign earned income exclusion may be available
Tax year	6 April to 5 April	Calendar year

Will the foreign tax credit cover the US tax on the sale?

Often, but not always. The foreign tax credit, claimed on Form 1116, can offset US tax only on foreign-source income in the same category, up to the US tax on that income. Five cross-border points decide the result:

1. The rate gap on the BADR slice. On the first £1 million of qualifying gain, UK tax at 18% is below the US 20% long-term rate, so residual US tax can remain, plus NIIT if it applies. Above the lifetime limit, UK tax at 24% is higher than 20%, which gives excess credits.
2. The capital gain rate differential adjustment. Section 904(b) reduces foreign-source capital gains taxed at preferential US rates in the limitation fraction. This cuts the credit you can use, even when UK tax looks high enough.
3. Recapture versus UK capital treatment. Where the US taxes recapture at up to 37% but the UK taxed the same amount as a capital gain at 18%, there is not enough UK tax to credit. Where the UK balancing charge was the larger figure, the result reverses.
4. Source and basket. Gain on goodwill is generally sourced where the goodwill was generated. Gain on other personal property sold by a US citizen resident abroad is foreign-source only in certain conditions, and the US-UK treaty's resourcing rule can help. Gains from selling an active practice usually fall in the general category. Share gains may start in the passive category, unless the high-taxed income exception moves them.
5. Timing. The UK tax year ends on 5 April and the US year on 31 December. An earn-out taxed upfront in the UK but on the installment method in the US creates a timing mismatch. Unused credits can generally be carried back one year and forward ten, and the choice between the "paid" and "accrued" methods of claiming affects when the credits arrive.

Is the Net Investment Income Tax creditable?

The IRS's position is that the 3.8% NIIT, reported on Form 8960, cannot be reduced by foreign tax credits under the Internal Revenue Code. Taxpayers have argued that treaty relief provisions override this, with mixed results in litigation under other treaties, and the position under the US-UK treaty is not settled. A treaty-based return position has to be disclosed on Form 8833 and requires careful judgement. For a sole trader or partner who materially participated in the practice, gain on active business assets is generally outside NIIT anyway, so the exposure is sharpest on a share sale.

How are sterling proceeds converted for the US return?

The US return is prepared in dollars. The amount realised is generally converted at the spot rate on the date of sale, and each asset's basis at the rate when it was acquired. A practice bought in 2008 and sold in 2026 can therefore show a US gain very different from the UK gain, because of the dollar-sterling movement alone. Deferred consideration receivable in sterling can produce separate section 988 currency gains or losses when it is paid. Proceeds placed on sterling deposit and later converted can do the same. Keep completion statements, bank credits and the exchange rate used for every receipt.

What does each sale-year return actually contain?

The UK self-assessment return

• SA108 capital gains pages reporting the goodwill, premises or share disposal, with the computation attached.
• The BADR claim, which must be made by the first anniversary of 31 January following the end of the tax year of disposal (for a 2026/27 sale, by 31 January 2029).
• Self-employment or partnership pages showing the final period's profits, the capital allowances balancing adjustment and any overlap or transition relief.
• Employment pages for post-sale associate or consultant income.
• Payment of CGT by 31 January following the tax year. Payments on account do not cover CGT, so the bill is often larger than expected.

The US federal return

• Form 1040 with a final Schedule C, or a Schedule K-1 position from Form 8865 for a partnership interest.
• Form 8594 for the asset allocation, Form 4797 for business property and recapture, and Form 8949 and Schedule D for capital gain.
• Form 6252 if the installment method applies. Electing out has to be done by the return due date, including extensions.
• Form 5471 for a practice company, including the section 1248 statement where relevant.
• Form 1116 for each category of income, Form 8960 for NIIT, and Form 2555 if post-sale wages are excluded.
• FBAR (FinCEN 114) and Form 8938, because large sterling proceeds in UK accounts sharply raise balances that must be reported.

Americans abroad get an automatic extension to 15 June and can extend to 15 October. Interest runs from 15 April on any unpaid US tax. For a sale in the first half of the UK tax year, the US return is due before the UK return, so the UK figures usually have to be estimated and confirmed later.

What if your US filings are behind before the sale?

Many American practitioners spent years in Britain without filing US returns, often thinking UK tax removed the obligation. A seven-figure practice sale followed by large inbound transfers, a Form 5471 that was never filed, or an unreported UK pension creates obvious risk. If earlier years are missing, the order of work matters. Catching up under the IRS Streamlined Foreign Offshore Procedures before filing the sale-year return usually means three years of returns, six years of FBARs and a non-wilfulness certification, with no penalty where eligible. Missing information returns such as Form 5471 are normally filed as part of that catch-up, or through a separate route where the streamlined procedures do not fit. Our FBAR penalty calculator shows the scale of exposure for unreported accounts.

A worked illustration

Consider a US-citizen dentist, UK-resident for fifteen years, trading as a sole trader, who sells in 2026/27 for £2.4 million: £1.9 million goodwill (self-created), £300,000 equipment and £200,000 deferred consideration payable in two years if she stays as clinical director. Figures are illustrative only.

• UK: the first £1 million of goodwill gain is taxed at 18% if BADR is claimed, and the balance at 24%. The equipment allocation causes a balancing charge because AIA was claimed. The £200,000 conditional on her staying could be challenged as employment income.
• US: the £1.9 million goodwill is long-term capital gain up to 20%. There is no NIIT because she materially participated. The equipment recapture is ordinary income up to 37%. The deferred amount may be wages eligible for the foreign earned income exclusion, or capital under the installment method, and the position has to match the UK treatment of the same payment.
• Credit: UK tax at 24% on the upper goodwill slice can shelter US tax on the lower slice within the same general category, subject to the section 904(b) adjustment. Whether any US tax remains depends on the exchange rate, the allocation and the timing of the UK payment.

How Jungle Tax prepares both returns

Jungle Tax prepares UK and US returns side by side, so the allocation, the character of each payment and the currency conversions agree across both. We check the sale documents for employment-linked consideration, reconcile UK capital allowances to US depreciation, work out foreign tax credit capacity by category, and file every information return the sale triggers. Where earlier years are missing, we deal with them first. Our US-UK tax accountants work regularly with high-net-worth professionals whose sale proceeds make every mismatch expensive. Our wider cross-border tax resources cover the surrounding reporting.

If you are selling, or have just sold, a UK dental, medical, consulting or veterinary practice as a US citizen, speak to us before the sale-year returns are due, and ideally before heads of terms are signed. Contact our cross-border team for a confidential consultation, and we will map both returns, the deadlines and the foreign tax credit position before you file.