This guide is **not** legal advice. It lists the questions accountants ask before they let you claim **non-residency** anywhere.
Scenario A — US citizen remote worker
Citizenship-based taxation means worldwide income reports to the IRS even if you live in Lisbon. FEIE and housing deductions help but do not erase filing duty. Budget $2k–$5k/yr for a cross-border CPA.
Compare cash using [US](/us/) vs [PT](/pt/) calculators only after FX and foreign tax credits are modeled professionally.
Scenario B — EU national in Estonia/Croatia nomad visas
Visa ≠ tax residency. If center of life (family, home, bank ties) stays in France, France likely taxes you even if you invoice through an Estonian OÜ. VERIFY Article 15 OECD tie-breakers.
Run [FR](/fr/) alongside your host country calculator with identical income.
Scenario C — UAE + offshore clients
Zero personal tax locally does not stop source countries from withholding on US/EU clients. CT registration may apply once profit scales—see [AE](/ae/) cost model.
Practical checklist
1. Count days per country (automate with calendar exports). 2. Map permanent home and economic interests. 3. Read treaty tie-breaker article order. 4. Document invoices + board minutes if using foreign wrappers.
Scenario D — UK resident, working from Bali
If your spouse, kids, and mortgage remain UK, HMRC may treat you as UK resident under the SRT even if you exceed 183 days elsewhere. Remote work for a UK employer is usually UK-source employment income—Article 15 may not rescue a beach laptop fantasy without a proper secondment.
Scenario E — Portugal without NHR
Post-2024 regimes change fast. NHR-style benefits are not assumed here. If you become Portuguese tax resident, progressive IRS + potential social on dependent activity apply—model [PT](/pt/) with your actual visa and contract type.
Stripe, Wise, and paper residency
Bank IBAN country and merchant account address do not set tax residency. They can, however, trigger AML questions and VAT MOSS nexus—keep ledgers aligned with substance.
OECD tie-breaker hints (simplified order—treaties vary)
Real treaties use precise wording; this is a study guide, not a substitute for Article 4 text. When in doubt, the competent authority route exists for dual-resident cases.
| Test (concept) | What auditors ask for |
|---|---|
| Permanent home | Lease deeds, utility bills, family location |
| Centre of vital interests | Where your business and personal ties concentrate |
| Habitual abode | Day counts across multiple homes |
| Nationality | Last-resort tie-break for individuals |
| Mutual agreement | MAP process if still dual after tests |
Companies use **Article 4(3)** corporate tests—different from individuals.
FAQ
Sometimes they defer social obligations; they rarely erase OECD residency tests.
Many countries use **183** as one test—not the only test.
Green card holders have **US filing** duties independent of FEIE—CPA required.
B2C rules may follow customer location—OSS or local registration.
Sourcing is messy—assume both countries may claim until advised.
Company formation ≠ personal tax residency in Estonia.
US withholding may still apply on US-source fees—treaty article matters.
Flight logs, leases, board minutes, invoices, and employer remote policies.