Both returns, one file
Two tax authorities. One set of figures.
Most cross-border problems are not caused by a hard rule but by a decision taken correctly in one country by someone who could not see its effect in the other. We prepare both returns from the same file, in the order that produces the right credits, and reconcile them before anything is filed.
Who this is for
- Americans in the UK who currently use two separate firms, or do one return themselves
- Dual citizens with income, pensions or property in both countries
- People moving between the US and UK in the year, where split-year and part-year rules apply on both sides
What we prepare
- Sequencing
- UK return first where UK tax drives the US credit; US first where US tax on US-source income is creditable in the UK.
- Apportionment
- UK tax-year figures mapped to the US calendar year with a documented, repeatable method.
- Treaty positions
- Pensions, Social Security, the saving clause and tie-breaker rules applied consistently, with Form 8833 where a disclosure is required.
- Reconciliation
- A one-page summary showing how each income type was treated on each return and why.
What you receive
Both returns, the reconciliation summary, the exchange-rate workings and a note of the elections made, all stored in your portal engagement so next year starts from a known position.
Process
How it works
- 01
Enquiry
All income sources in both countries, filing history on each side, and any moves during the year.
- 02
Written quote
One fee covering both returns and the reconciliation.
- 03
Onboarding and documents
A single document list covering both sides.
- 04
Preparation in sequence
Prepared, reconciled and reviewed by a second person.
- 05
Review and filing
You approve both returns in the portal; we file with HMRC and the IRS.
FAQ
Questions we are asked
Why not use a UK accountant and a US accountant?
You can, but each will only see half the picture, and the credit on one return depends on the figures from the other. A single file avoids the mismatches that generate HMRC and IRS queries.
Which return is prepared first?
It depends on where the income arises. UK employment income is taxed first in the UK, so the UK figures feed the US Foreign Tax Credit. US-source income is often the other way round. We set the sequence out at the quote stage.
Written by the US UK Expat Tax advisory team. Last reviewed 7 November 2026
Primary sources checked
General information, not personal tax advice. Rules and thresholds change; we confirm the position for your facts before any work.
Get started
Tell us your situation
Where you live, which years are involved, what has been filed, and every source of income in each country. We reply by email within two working days with what is needed and a written fee. No free consultations, and no work starts before you have the quote.