Gay couples in Zurich are to be granted greater equality, although their rights still fall short of those enjoyed by heterosexual couples.
Voters on Sunday came out in support of an initiative that would allow gay couples to be taxed together.
Gay men and women will also be given the automatic right to visit their partners in hospital. Until now, visitation rights were only guaranteed to heterosexuals.
The new legislation also deals with gay foreigners who have set up home with a Swiss partner. They will now receive the same rights as foreign heterosexuals who have married a Swiss.
Zurich is the second canton to have granted gay couples more rights - similar legislation has already been passed in Geneva.
However, gay rights campaigners say Switzerland is still a long way behind its European neighbours, many of which have allowed registered homosexuals partnerships since the early 90s.
For instance, the vote does not deal with the issue of gay marriage, which is still not legal in Switzerland, nor does it allow homosexual couples to adopt children.
However, supporters of initiative said they hoped that the "yes" vote in Zurich would subsequently be taken up at national level and would in due course pave the way for gay marriages.
Registration of gay couples
Prospective couples will have to live together for at least six months before being registered.
After registration they would receive the same rights and obligations as married couples in regard to taxation and social welfare.
The partnership can be ended immediately by mutual consent or by just one partner if there has been a separation period of at least two years.
The partnership would also end automatically if one partner leaves the canton of Zurich or gets married.