Many cities have made face coverings mandatory on public transit, including Toronto, Fredericton, Moncton and Saint John. Children under the age of two and those with certain medical conditions are exempt.
Mayor Mike Savage said a similar bylaw in Halifax is "always under review," however, right now, it would be difficult to enforce.
"How does a bus driver up at the front of the bus be responsible for making sure everyone getting on at the rear of the bus is wearing their mask at all times," he asked. "It puts a lot of stress on the bus driver to make sure that happens."
Currently, passengers are required to board buses through the rear doors unless they need to use the ramp for accessibility.
Because of this, fares are waived, however, the HRM is in the process of installing temporary polycarbonate shields next to bus drivers to keep them a safe physical distance from passengers.
"I'm not sure exactly when we'll be able to do front loading again, but that would mean we'd be able to collect revenue and it also means we can look at doing other things, like monitoring who is wearing a mask and who isn't," Savage told NEWS 95.7's The Rick Howe Show.
For now, Halifax Transit is "strongly encouraging" passengers to wear a mask.
Staff have been out this week handing out free masks at terminals throughout the municipality. The times and locations are being posted on the @hfxtransit Twitter account.
HRM spokesperson Erin DiCarlo said they currently have a supply of 20,000 masks they're giving away to passengers.
"Between 2,500 and 5,000 masks will be available at each event," said DiCarlo in an emailed statement. "These events will continue while supplies last."