1. Establish UK residence for each relevant tax year
Prepare day counts, home and work evidence, family and accommodation facts, and the individual's recent UK residence history. Eligibility for the four-year foreign income and gains regime depends on residence status and prior non-residence.
Do not infer tax residence from nationality, immigration permission or payroll location. These are relevant facts, not substitutes for the statutory residence analysis.
2. Identify the foreign income and gains categories
List overseas employment, business, property, investment and disposal amounts by country and date. Separate arising amounts from historic funds and establish the source and ownership of each item.
The FIG regime applies from 6 April 2025 for qualifying new residents. Claims are made through Self Assessment for relevant categories, and their wider consequences should be calculated before filing.
3. Build Overseas Workday Relief from the workday evidence
For internationally mobile employees, connect the employment contract, payroll, travel calendar and actual duties. Record where each workday was performed and retain evidence for travel and work location.
Apportionment, qualifying periods and any cap must be applied using the current rules. A broad estimate of days abroad is not a reliable filing position.
4. Coordinate the return with payroll and cash flow
Review PAYE operation, tax codes, employer reporting and any expected Self Assessment liability. Relief on the return does not automatically correct payroll during the year.
Where cash-flow treatment is available, make applications and payroll arrangements on time rather than relying on an eventual refund.
5. Deal with overseas tax and treaties separately
Identify foreign filings, withholding tax and the other country's residence or source position. Double-tax relief depends on the treaty and domestic rules; it is not simply a credit for every overseas payment.
Use an adviser in the other jurisdiction where local law or filings are material, and reconcile both sets of advice around the same income and dates.
6. Maintain a year-by-year international tax file
- Residence timeline, day count and supporting travel records.
- Foreign income and gains schedules with exchange rates and tax paid.
- Employment duties, payroll and workday allocation.
- Claim decisions and the effect on allowances and future years.
- Treaty analysis and overseas adviser correspondence.
Official sources and further reading
These primary sources support the framework above. Check the current version before acting because tax law and HMRC guidance can change.