The claim dictates the paperwork
The FIG regime is unusually record-hungry because of how the claim works. HMRC's Residence and FIG Regime Manual at RFIG42100 requires the relief to be claimed on a source by source basis, with the amount quantified in the return, and helpsheet HS266 has the relieved amounts reported on the normal supplementary pages. You cannot do that from memory or from a single year-end balance. For each foreign source you need the underlying documents: bank and broker statements, dividend vouchers and interest certificates, fund distribution statements, employment contracts and payslips where foreign employment income is involved, and for each disposal the acquisition date, cost and proceeds so the gain can be computed. Foreign amounts also need converting to sterling, so keep your exchange rate workings. Our SA109 walkthrough shows where each figure lands on the return.
Evidence for eligibility, not just amounts
The quieter half of the file is residence evidence. Qualifying for the regime turns on being in your first 4 tax years of UK residence after at least 10 consecutive non-resident tax years, so your records should let you demonstrate both: travel records and day counts for the years around your return or arrival, and the facts behind any split-year or treaty position. This is the material HMRC would test first if it enquired into a claim, and it is much easier to assemble now than five years from now. If your day counts in earlier years were ever close to the line, our guide to the Statutory Residence Test explains what the counts actually decide.
How long to keep everything
GOV.UK sets the baseline: anyone who files Self Assessment must keep records, HMRC can charge a penalty if they are not accurate, complete and readable, and paper or digital formats are both fine. On timing, keep records for at least 22 months after the end of the tax year the return is for if you file on time, so a 2025/26 FIG return filed by 31 January 2027 means keeping records to at least the end of January 2028. File late and the rule becomes at least 15 months after you sent the return. The self-employed must keep business records for at least 5 years after the 31 January deadline. For FIG claimants we suggest treating the longer period as the practical standard anyway: the claim window for 2025/26 runs to 31 January 2028, and offshore matters are exactly where HMRC enquiries reach back furthest. Good records also set your penalty position, because HMRC's guidance on penalties describes keeping adequate records and asking about uncertainty as taking reasonable care, the band where inaccuracy penalties can be zero. Our guide on what happens when the FIG regime goes wrong shows what is at stake.
How Horizon builds the file with you
Assembling a source by source file across foreign banks, brokers and currencies is most of the work of a FIG return, and it is work Horizon UK Tax Solutions does every week. The practice is founder-led by a Chartered Tax Adviser with over 10 years experience, including 7 at a Big Four firm, and FIG returns are exactly the returns we specialise in. We tell you precisely which documents we need, quantify each source, and file the SA109 claim for a fixed fee agreed upfront: non-resident and expat returns £750 fixed, complex returns from £950. Book a free 30-minute clarity call or see our non-dom and residency services.