The single-member US LLC is the cheapest, fastest business vehicle in the United States. It is so common that UK entrepreneurs operating in the US frequently default to one without thinking about how HMRC will see it. The mismatch between US and UK characterisation of LLCs is one of the most consequential traps in personal international tax, and we still meet UK clients who have been filing returns wrongly for years.
The pass-through illusion
For US federal tax purposes, a single-member LLC is "disregarded as an entity separate from its owner" by default. The IRS treats its income, deductions, and gains as if they belonged directly to the member. A US-resident sole owner files Schedule C with their personal return and reports the LLC's net profit as self-employment income. Multi-member LLCs file Form 1065 partnership returns and pass income through to members on K-1s. Either way, no entity-level federal income tax is paid, which is why founders love them.
The problem is that "disregarded for US tax" does not mean "disregarded everywhere". HMRC's settled position, going back to the Anson case and the resulting HMRC guidance, is that a US LLC is generally an opaque entity for UK tax purposes. The LLC's profits are not treated as the UK member's own income as they arise. Instead, the UK member is treated as holding shares in a company, and distributions are taxed when received.
What the Anson decision did and did not change
In 2015, the Supreme Court ruled in Anson v HMRC that a particular Delaware LLC was transparent for the limited purpose of double tax relief, allowing Mr Anson to claim a credit for US tax on the same profits taxed in the UK. The decision was narrow, fact-specific, and concerned a multi-member LLC with a particular operating agreement that gave members a present right to profits.
HMRC accepted the decision but did not extend it to the general characterisation question. Its published view remains that LLCs are opaque, and Anson should not be read as a general transparency rule. For single-member LLCs and most multi-member LLCs without the specific Anson features, the safe assumption is that HMRC will treat the LLC as a corporation for UK tax purposes.
What this means in practice
A UK resident who owns a US LLC that generates profit faces three layers of risk. First, the LLC's profits are taxable in the US (federal and state), even though there is no entity-level federal income tax. The owner files personal US returns. Second, HMRC will not tax those same profits in the UK as they arise. Instead, UK tax is due when the LLC distributes cash to the member, who reports it as a dividend.
This creates a mismatch in timing. US tax is paid now on the LLC's profits. UK tax is paid later when distributions are made. Double tax relief is not automatic because the underlying profits were taxed in the US in a different tax year from when the UK tax becomes due on the distribution. The Anson route to immediate relief is closed for most fact patterns.
Controlled Foreign Company (CFC) rules
If the LLC is treated as a company and is controlled by UK resident persons, the UK CFC rules under TIOPA 2010 Part 9A can apply. The CFC charge is designed to attribute the profits of a low-taxed foreign company to its UK controlling shareholders to prevent profit shifting. Most LLCs taxed at full US federal and state rates will not fail the tax exemption gateway, but holding companies, IP holding LLCs, and LLCs in states with low income tax can fall within scope.
The exemptions under Chapters 11 to 14 of Part 9A are the usual escape route. The most relied-on are the excluded territories exemption and the low profits exemption (under GBP 200,000 of accounting profits in the period). Each requires testing every year and documenting the analysis.
Hybrid mismatches
If your LLC is part of a larger structure with multiple entities and you are claiming deductions, watch for the UK hybrid mismatch rules under TIOPA 2010 Part 6A. These rules deny deductions where an entity is treated differently in the UK and another jurisdiction, leading to a deduction without inclusion or a double deduction. They were originally aimed at large multinationals, but the rules apply by their terms to small structures too.
Practical guidance for UK residents
If you are a UK resident considering a US LLC, the planning conversation should happen before you form it, not after the first profit shows up. Sometimes a US C-corporation is cleaner because both jurisdictions treat it as a company. Sometimes a UK Ltd with a US branch works better. Sometimes the LLC structure is right, but it needs the right operating agreement, the right state, and a clear distributions policy.
How PushDigits supports cross-border owners
Our tax planning team works with UK residents who operate in the US, including those running tech companies, consulting practices, and e-commerce businesses. Our business advisory team coordinates with US-side advisors to align UK and US treatment from day one.
If you already own a US LLC and are unsure how it is being treated for UK tax, book a structuring review or contact us. Restating prior years is possible but unpleasant. Getting it right at formation is much easier.