Prenup: United States + Switzerland

Which contract, and where to sign it

United States: Written and signed (UPAA/UPMAA): voluntariness, full disclosure, reasonable time to reflect; notarisation and witness rules vary by state.

Switzerland: A notarial deed (öffentliche Beurkundung); concluded before or at any point during the marriage.

Several legal systems are involved — one document will not cover them all. The working construction: an anchor contract in the principal jurisdiction plus mirror texts where the key assets sit, backed by local counsel opinions.

Choice of applicable law

English and US courts will judge the contract by their own rules whatever law it names — for these jurisdictions the signing procedure decides, not the choice-of-law clause.

What you can fix in it

United States: Assets and alimony (waivable in many states absent unconscionability); child support and custody cannot be locked in.

Switzerland: Election among the statutory regimes (separation, community) and adjustment of accrual shares; the statute sets the frame — freeform constructions fail.

What gives the contract its force

Full asset disclosure annexed to the contract — the main anchor against future challenge.

Independent counsel for each side; one adviser for both is the classic line of attack.

Translations and legalisation: every version with a notarised translation and apostille for its jurisdiction of use.

What to read next

Deep dive: cross-border prenups

Divorce navigator: what happens without a contract

Property division in a cross-border divorce