SRT Split-Year Treatment: When a UK Tax Year Divides, and When It Refuses To (2026)

The UK tax year is all-or-nothing by default: resident for the year, or not, decided by the SRT. Split-year treatment is the exception that makes real-world moves workable, dividing one tax year into a UK part and an overseas part, but it is narrower than movers assume, and it is never something you elect: either your facts fit a case or the whole year stays resident. The rules sit in HMRC's RDR3. Updated 5 August 2026.

The eight cases, in plain shape

Leaving cases: starting full-time work overseas; the partner of someone doing so; and ceasing to have any UK home. Arriving cases: starting to have your only home in the UK; starting full-time UK work; ceasing full-time work overseas on return; and the partner counterparts. Each case carries its own conditions, and crucially its own day limits inside the split period: the work-abroad cases, for instance, restrict UK days and workdays during the overseas part on a pro-rata version of the familiar limits. Several cases can apply at once; RDR3 sets priority rules for which governs, which changes the split date, which changes what is taxed where.

The traps

• It is conditional, not automatic. Fail a condition mid-year (too many UK days after departure is the classic) and the year un-splits retroactively.
• The split date is contestable. A few days' difference in when the overseas part begins can move a bonus or a gain across the line.
• It only exists if you are resident for the year. Split-year is a carve-out from a resident year; non-residents do not need it.
• Treaties still lurk. Even in a split year, the other country's rules and the treaty can complicate the clean halves; see dual residency.

Day counts decide it, again

Every case turns on dated facts: when the home ceased, when the work started, and how many UK days fell in each part. The Days Monitor iPhone app keeps the day-by-day record that fixes those dates, with custom rules for the reduced in-split limits and exports your adviser can lay against RDR3's conditions. Work the base position first with the free SRT tool, and if the move is permanent, read the leaving-the-UK guide. Download it on the App Store.

Sources

• HMRC, RDR3: Statutory Residence Test (split year sections) (accessed 5 August 2026)

This article is general information, not legal, tax or immigration advice. Rules change and your facts matter; verify with the official sources linked above and take professional advice.