1931
- The first LeCoultre Reverso watches are produced.
- Gérald Charles Genta is born on 1 May 1931 in Geneva.
- The first Swiss Watch Fair is held in Basel, with 32 companies exhibiting.
- Rolex introduces watches with automatic winding (called "perpetual").
- The Citizen wristwatch brand is launched in June.
- On August 14, ASUAG is formed by Ebauches SA as a federation of Swiss watch companies.