NDP MPP Cheri Di Novo wants the TTC to run the UP Express, which travels from Union Station to Pearson International Airport.
Di Novo is also asking for more stops along the route.
The UP Express currently stops at the Bloor and Weston GO stations, linking up with GO Transit. It is currently operated by Metrolinx.
Di Novo told the Toronto Sun that if the TTC took over operations, the UP Express could be used for commuter relief.
Earlier this year, Metrolinx announced it would be cutting its rates because it was struggling to attract passengers. Metrolinx had originally set a goal of 5,000 riders per day for the first year of service, but was only averaging about 2,300 riders each day.
It now costs $12 to travel between Union Station and Pearson International Airport, down from $27.50. Riders travelling with a Presto card will pay $9, down from $19.
Watch a video explaining the costs below, or click here to view it on mobile.