State tax: the filing obligation that ignores the treaty.
Leaving the United States settles your federal position far more cleanly than your state one. States are not party to the US-UK treaty, do not recognise the Foreign Earned Income Exclusion in every case, and several take an aggressive view of who has really left.
Residency is a state-by-state question
Most states treat you as resident while you remain domiciled there, whatever your federal position. California, New York, Virginia, New Mexico and South Carolina are the ones we most often see continuing to assert residency after a move abroad, looking at property, licences, voter registration, bank accounts and family ties.
States with no personal income tax — Florida, Texas, Washington, Nevada and others — make departure straightforward. Where you left from matters more than where you now live.
- Part-year returns in the year you leave
- Nonresident returns for continuing state-source income, such as rent
- Treaty relief generally does not bind the states
Documenting the break
Breaking state residency is evidential. Surrendering the driver's licence, changing voter registration, closing or relocating accounts, moving professional registrations, and severing the property connection all build the record — and the year of the move is when to build it, not three years later under enquiry.
We review your state position as part of every federal engagement, file the part-year or nonresident returns that are genuinely required, and document the departure where they are not.
Questions we get about this
It depends which state you left. Some release you on departure; others continue to treat you as resident until domicile is clearly broken.
The year of the move almost always needs a part-year return regardless.
California is the most persistent, with New York, Virginia, New Mexico and South Carolina also known for it.
They examine ongoing ties rather than just your address, so the evidence you keep matters as much as the move itself.
Generally not. States are not parties to the federal treaty and most do not follow it, so treaty positions that work federally can fail at state level.
Some states also decline to follow the Foreign Earned Income Exclusion, taxing income the IRS never sees.
That is state-source income, so a nonresident return in that state is usually required even after residency is broken.
It sits alongside your federal return and your UK Self Assessment, with credit relief coordinating the three.
Last reviewed . Thresholds and rates change annually — check figures against the current tax year before relying on them.
Not sure how this applies to you?
Describe your situation and we will tell you which forms are actually required, with a fixed fee to prepare them.