From January 1, 2011 someone wanting to get married in Switzerland will need a valid residence permit or visa.
The date for the new legislation, which aims to cut down the number of marriages of convenience involving rejected asylum seekers and people living in Switzerland illegally, was set by the government on Friday.
Both parliamentary chambers last year agreed the bill, proposed by the rightwing Swiss People’s Party.
The Federal Migration Office investigates about 500 suspected sham marriages every year.
swissinfo.ch and agencies