After 46 new cases of Covid-19 were recorded in Geneva on Thursday, State Councillor Mauro Poggia announced masks would be compulsory in retailers in the canton from 28 July 2020, according to RTS.
The canton of Geneva follows Vaud and Jura, two cantons that introduced a similar requirement from 6 July 2020.
Washing hands with an alcohol-based hand sanitiser will also be required before entering shops in Geneva.
In addition, hairdressers and staff working in beauty salons will need to wear masks from next Tuesday.
From 8pm on Friday all bars and nightclubs in the canton must ensure they have a reliable process for identifying and recording the contact details of patrons. All staff in bars, clubs and restaurants must also wear masks.
The measures will remain in place until 1 October 2020, with a possibility of extension. Businesses failing to comply with the new rules could be fined as much as CHF 10,000.