What is Centre of Life Test?

How it works

"Centre of life" is the domestic-law cousin of the OECD treaty concept of centre of vital interests. Where the OECD treaty rule applies only to dual residents (and only as a tie-breaker), the centre-of-life test built into many domestic statutes is a standalone residency trigger — it can establish residence even when day-count tests fail.

Country variations:

• Spain uses núcleo principal o base de actividades o intereses económicos — the main hub of activities or economic interests. A Spanish tax authority may keep you resident if your main business assets, primary income source, or family base sits in Spain, regardless of presence below 183 days. Add the family-presumption rule (spouse + dependent kids in Spain → presumed Spanish-resident) and the test gets sharp teeth.
• France layers article 4B CGI: tax residence if any of (i) your foyer (family home) or lieu de séjour principal is in France, (ii) your principal professional activity is in France, or (iii) your centre des intérêts économiques is in France. Centre of economic interests = where main investments are managed, where your business sits, where you draw most income.
• Italy uses domicilio civile (the seat of personal and economic affairs) as one of three residency triggers alongside residenza anagrafica and 183 days.
• Argentina, Brazil, Mexico apply analogous "centro de intereses vitales" tests.

The test is fact-intensive. Tax authorities reconstruct your life from ATM withdrawals, mobile-phone records, school registrations, gym memberships, club memberships, healthcare providers, vehicle registrations, voter registration, where your dog is registered. None of these alone are decisive; together they can be conclusive.

Examples

• Tech founder relocates from Madrid to Lisbon. Spends 250 days in Lisbon, 100 days in Madrid. Wife and two children stay in Madrid for the school year. Spanish AEAT challenges the move using the family-presumption rule. The founder loses the residency dispute despite under-183 days of Spanish presence — Spain's centre-of-life test wins because the family base is unchanged.
• French consultant moves to Dubai. Spends 220 days in Dubai with a UAE rental and bank account. Closes French bank accounts, moves vehicle registration, relocates dog. France challenges via the foyer limb of article 4B because his wife and adolescent children remained in Lyon. The treaty tie-breaker may save him — domestic tests don't.

Common mistakes

• Believing 183 days is the whole story. Centre-of-life tests in civil-law countries can hold you resident with much lower day counts.
• Underestimating family ties. Spouse and dependent children remaining in the source country are the single most decisive element in nearly every centre-of-life dispute.
• Skipping the documentation cycle. A clean break needs proactive evidence: gym, doctor, banks, schools, dog all moved. Building it after a challenge is much harder than building it before.
• Conflating with the OECD treaty test. Centre of life (domestic) ≠ centre of vital interests (treaty). Different tests, different triggers, different remedies. Both can apply to the same person.