The two systems in one sentence
Swiss inheritance law starts from forced heirship: a reserved share, or Pflichtteil, guarantees specific relatives a statutory minimum portion of your estate no matter what your will says. US inheritance law starts from testamentary freedom: with few exceptions, you decide who gets what. For Americans living in Switzerland, the practical question is which system governs your cross-border estate.
What Swiss law applies by default?
If you are habitually resident in Switzerland, Swiss law generally governs the succession to your estate unless you make a valid choice of law. Under the Swiss Federal Act on Private International Law (PILA), forced heirship rules then impose Pflichtteile on certain heirs.
- Descendants' reserved share is now one half of their statutory entitlement, down from three quarters.
- Parents no longer have a forced share.
- A surviving spouse or registered partner retains a reserved share of one half of their statutory entitlement.
Choosing US law: the professio juris clause
A professio juris is an express choice-of-law clause in a Swiss will or succession agreement. It lets a foreign national elect the law of their home country for their estate, which can bypass Swiss forced heirship and restore something closer to US testamentary freedom. The clause must explicitly reference the Swiss Federal Act on Private International Law and be made in a form valid under Swiss law. For the bigger picture on how this fits into a complete cross-border plan, see our guide to estate planning for US expats in Switzerland.
January 2025 PILA update
The revised Article 91 PILA is significant for dual US-Swiss citizens: they can now elect the law of their other nationality — an option previously unavailable to them. However, Swiss law on statutory entitlements (Pflichtteilsrecht) remains reserved for dual nationals, meaning Swiss forced heirship minimum shares may still apply even after a professio juris electing US law. Before the update, Swiss dual nationals were generally excluded from making any such election.
What the 2023 Swiss reform changed for families
The January 1, 2023 reform gave families more room to plan. If you leave both a spouse and descendants, the reserved shares for the spouse and the descendants each amount to 25% of the entire estate, leaving 50% freely disposable. Before the reform, descendants could claim more, and parents still had a forced share.
Cross-border complications: US estate tax and Swiss retirement assets
US citizens and green-card holders remain subject to US federal estate tax on worldwide assets regardless of residence. The federal estate tax exemption is $15 million per individual in 2026 ($30 million for married couples) under the One Big Beautiful Bill Act (OBBBA), signed into law on July 4, 2025. Unlike the TCJA increase, this $15 million baseline is permanent with no sunset provision and will be indexed for inflation starting in 2027. In parallel, Swiss second-pillar pension and third-pillar 3a assets often pass through statutory beneficiary rules outside the ordinary will, so they need to be coordinated with any choice-of-law plan.
Swiss real estate adds another dimension: Lex Koller restricts foreign ownership of Swiss property, which can complicate inheritance when a US-citizen heir wants to keep rather than sell the property. If the deceased owned Swiss real estate through a trust, the 2026 Swiss Supreme Court ruling on foreign trusts may also affect the transfer. For a detailed walk-through of the inheritance process itself, see our guide to inheriting from Switzerland as a US citizen.
Practical steps for cross-border estate planning
- Confirm your habitual residence and citizenship status, including any dual nationality.
- Make an express professio juris election in a Swiss will or succession agreement if you want US law to govern — but if you are a dual citizen, account for the reserved Swiss forced heirship provisions that still apply.
- Review Swiss pension and 3a beneficiary designations separately from your will.
- Coordinate with US estate tax planning, especially if your worldwide estate may exceed the $15 million exemption.
- Revisit your plan after any citizenship, marital, or cross-border move.
At US Expat Wealth, we help Americans in Switzerland think through both systems together so Swiss rules and US rules don't work at cross purposes. This article is educational only and not legal or tax advice; the right structure depends on your individual family and asset situation.