What are the five statutory residence test ties and how is each one determined?

1. Family tie — does someone close live in the UK?

The family tie exists if a spouse, civil partner or a minor child is UK resident in the tax year under consideration; full‑time students are treated specially under the guidance, and same‑sex relationships have raised interpretive questions in practice, meaning precise circumstances matter ^{[3] [4]}. In short, if a taxpayer’s legally recognised partner or dependent child is resident in the UK during the year, that relationship constitutes a tie for the sufficient ties calculation ^{[3] [5]}.

2. Accommodation tie — is there a place to stay available?

The accommodation tie arises where the individual has a place to live in the UK that is available for their use for a continuous period of at least 91 days, and the individual spends at least one night there in the tax year; HMRC distinguishes “accommodation” from “home,” so even holiday lets or temporary retreats can count if they meet the availability and use tests ^{[3] [6]}. The test looks at permanence and stability: the accommodation must be more than fleeting if it is to qualify, and precise facts control the outcome ^{[6] [5]}.

3. Work tie — are substantial work duties performed in the UK?

The work tie is met if the individual works in the UK for 40 or more “working days” in the tax year under HMRC’s definition, with the guidance treating training, travel time and certain duties as work for SRT purposes; the distinction between incidental and substantive duties matters for taxability but not for the SRT tie itself ^{[3] [6]}. HMRC’s manuals and practitioner notes make clear that determining whether days count as “working days” requires detailed factual assessment, and different tests apply for “full‑time work overseas” exceptions ^{[3] [6]}.

4. 90‑day tie — did the person spend 90+ days in recent years?

The 90‑day tie is an historical lookback: it is present for the tax year if the individual spent more than 90 days in the UK in either of the two tax years immediately before the year under consideration; importantly, those prior‑year days are counted by tax year, not added together across years ^[7]. This tie therefore links current residency risk to recent patterns of presence in the UK and can push someone over the residency threshold even if current‑year days are limited ^{[7] [2]}.

5. Country tie — is the UK the country where most days were spent?

The country tie applies only if the taxpayer was UK resident in one or more of the three tax years before the year under consideration; it is present where the UK is the country in which the individual spends the greatest number of days in the tax year ^{[8] [9]}. Because it is conditional on prior‑year residency, the country tie is the one tie that newcomers (non‑residents in the prior three years) can generally ignore, but for leavers it often proves decisive when combined with other ties ^{[2] [4]}.

Counting ties against day thresholds in statutory tables — which differ depending on whether someone is an “arriver” (not resident in the prior three years) or a “leaver” (was resident in one or more of the prior three years) — determines residency under the sufficient ties test, and HMRC guidance and flowcharts are explicit that the rules are complex and fact‑sensitive, so documentary records and professional advice are commonly needed ^{[2] [3] [5]}. Where reporting or summaries omit nuances — such as definitions of “working day,” the accommodation availability test, or special rules for students and deceased persons — reference to HMRC’s RDR3 guidance and internal manuals is essential to resolve borderline cases ^{[1] [8] [7]}.