The Office québécois de la langue française (OQLF), or French language office, began mailing warnings to companies that fail to showcase trademarked names in both English and French.
The OQLF has sent dozens of letters warning stores they could face fines if their business names to not comply with the French Language Charter.
Stores such as Second Cup, for example, have added the words "les cafés" to abide by the rules.
Martin Bergeron, member of the OQLF, said businesses that do not comply with these rules cannot get subsidies or contracts from the government, and they could be fined.
Companies that do not add translations to their signs could face fines up to $25,000 and twice as much for repeat offenders.
Nathalie St-Pierre, the Retail Council of Canada's vice president for Quebec, said the OQLF is targeting stores on a case-by-case basis.
Some of the Retail Council's members say they may go to court to keep their business name unchanged.