The event was organized on Facebook by two Geneva residents who formed a protest group in August.
The duo, who say they pay nearly 20 percent of their income on health insurance premiums, told news agency ATS they were happy with Saturday's turnout – estimated as 500 by police but 800 by organizers.
“We didn't know if it would be just us two,” they said.
The pair said they wanted to lend their support to the fight for a reorganization of the existing health insurance system, which has seen costs spiral in recent years.
A cantonal initiative was recently launched by the political left in Geneva aiming to cap basic health insurance premiums at ten percent of a household's income.
Campaigners have until March 2018 to gather the required number of signatures to push it to a referendum.
Geneva residents pay among the highest premiums in Switzerland for their compulsory basic health insurance (LaMal), which provides the same cover wherever you live in the country but is calculated on the costs to insurers of providing healthcare in that canton.
Since the law on compulsory health insurance came into force in 1996 the average standard premium has risen by 4.6 percent a year, taking monthly payments from 173 francs in 1996 to 428 francs in 2016.
Premiums are set to go up again by four percent in 2018.
In 2016 the Swiss upper house of parliament rejected a similar initiative to cap premiums at federal level, saying it should be up to the cantons to legislate on the issue.