Who we help
Contractors & freelancers
Invoicing across the Atlantic raises self-employment tax, social security and, in the UK, employment status.
Two systems both want to call you self-employed, and charge for it.
Working for clients in one country while living in the other puts you in both tax systems on the same income, with two separate social security regimes attached.
The totalisation agreement stops you paying into both, but only if it is claimed properly and evidenced.
What we handle
01
Self-employment tax
US self-employment tax is not covered by the foreign earned income exclusion, and surprises people who assumed the exclusion handled everything.
02
Social security
The US–UK totalisation agreement decides which system you contribute to. A certificate of coverage is the evidence.
03
Structure
Sole trader, UK limited company or US LLC all read differently across the border, and an LLC is a particular trap.
04
IR35 and status
UK off-payroll rules can recharacterise your engagement regardless of what the contract says.
Why us
The LLC problem
A US LLC is often the default recommendation from a US adviser and is frequently the wrong vehicle for someone UK-resident, where it may be treated as opaque and produce double taxation with no credit.
We look at the structure before the invoices start, because changing it later is disruptive.
Frequently asked
Do I pay social security twice?
You should not. The totalisation agreement assigns you to one system, and a certificate of coverage evidences it to the other. It needs applying for rather than assuming.
Is a US LLC a good idea if I live in the UK?
Often not. HMRC's treatment of LLCs can leave you taxed in both countries without relief. It is worth specific advice before incorporating one.
Does the foreign earned income exclusion cover self-employment tax?
No. The exclusion applies to income tax only. Self-employment tax remains due unless the totalisation agreement assigns you to the UK system instead.
What is a certificate of coverage?
Evidence from one country's social security authority that you contribute there, which exempts you from the other's charge. It is applied for, not assumed.
Should I use a UK limited company?
Often sensible for UK purposes, but if you are a US person it brings Form 5471 and potentially GILTI. Workable, provided it is planned rather than discovered.
How does IR35 interact with US tax?
IR35 changes how the UK taxes the engagement and can shift you to deemed employment. The US position follows your own status, so the two can diverge and need reconciling.
Can I invoice a US client from the UK?
Yes, and where that income is taxed depends on where the work is performed and your residence, not where the client is. Withholding forms such as W-8BEN are usually involved.
Invoicing across the Atlantic raises self-employment tax, social security and, in the UK, employment status.
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