The Toronto Transit Commission is considering replacing its current single-use, one-way “continuous trip” transfer system with another that would allow travel, in any direction, during a specific time period.

The switch would give commuters as long as two hours to travel in any direction on the public transit system.

"The approach has been requested frequently by customers to aid them in making stop-over transit trips (for daycare, dry cleaning, etc.) and for short return trips (e.g. out and back to lunch) typically at off-peak times," according to a report that will go before the TTC board on Tuesday.

Under the existing system, when riders pay their fare, they can take a transfer that allows them to board the next TTC-operated vehicle on a connecting route. But travellers who stop to run an errand, and then continue on the same route, are required to pay another fare.

The idea, however, may come at a cost to commuters.

TTC spokesperson Brad Ross said the introduction of a time-based transfer system will mean a loss in revenue for the transit commission.

"In essence, (we are) losing revenue because people are no longer having to pay another fare when they get back on the system," Ross told CTV Toronto.

The report says introducing transfers valid for two hours would result in $20 million of lost revenue annually, while a 90-minute transfer would result in $12 million in lost revenue.

But that financial loss could eventually translate into a gain for the TTC, as the transit commission projects more people will consider taking public transportation.

Ross warns, however, that an increased ridership could also reduce revenues.

"When ridership grows, so do our costs. Because you have increased ridership, yes you have increased revenue, but you also have increased costs because you have to put the service on the street to meet that ridership demand, and that’s where the real costs are."

A pilot of the time-based transfer system is currently being tested out on the 512 St. Clair route. Customers can board a 512 St. Clair streetcar or bus at any stop, in any direction, until the expiration time shown on the transfer.

The proposal to introduce a time-based transfer system makes sense as part of the wider Presto fare card rollout, the report explains. Metrolinx has said full deployment of Presto terminals across the TTC will begin sometime this year, and should be complete by 2016.

"Implementing a time-based transfer system will make the implementation of a transfer system easier for PRESTO and therefore save development costs and east implementation," the report states.