The MBTA won't be reinstating late night bus service. Before commuters can rely on the agency to get them to work in the wee hours of the morning, the T says it needs to find a way to keep costs down for the proposed line.

The T's board delayed a vote Monday on a nine month pilot project to offer bus service along a key corridor from Mattapan Center to Revere that would connect downtown and job centers like the airport and Longwood Medical Center.

"So we are proposing with this a way we can connect residents throughout Boston, Chelsea, Revere and beyond to some of the great job centers in  our area," said Chris Osgood, a proponent of the line who works with the coalition that presented the proposal to the T's Fiscal and Management Control Board Monday.

The MBTA estimates that late night buses will serve 75,000 riders annually, about 200 rides per night. That level of ridership will bring in $38,000 a year in fares but it will cost the T over $2 million to operate it, meaning each trip will cost the state $27 in subsidies.

MBTA General Manager Luis Ramirez opposes moving forward with the plan, telling the board Monday in his remarks that the T must show fiscal discipline before adding services.