It is the second try at late night public transportation, and MBTA officials will be watching its performance closely. The Night Owl bus service was offered from 2001 to 2005, but was axed because revenue from paltry ridership failed to cover growing costs.

The one-year pilot program will provide weekend service until 3 a.m. on the subway system and the 15 most popular bus routes, T officials said Wednesday.

The T’s long-awaited late-night weekend service is slated to debut March 28, an effort by city and MBTA officials to make Boston more appealing to younger residents, innovation workers, and other people who stay out long past midnight.


The new late-night service also plays a key role in Mayor Martin J. Walsh’s endeavors to encourage a more vibrant night life in the city, possibly including, he indicated last week, plans to keep bars and clubs open later.

“It’s not just about the social vibrancy of the city, but it’s also about blue-collar workers, and the T is the way they’d like to get home: the busboy, the bartender, the cook, the line chef,” Transportation Secretary Richard A. Davey said Wednesday.

If the service does not prove popular with riders, it could be nixed next March. The pilot comes as a directive from Governor Deval Patrick, and the results could help define his transportation legacy.

The formal announcement and a list of corporate sponsors who have agreed to help offset the $20 million cost will be made by Patrick Thursday morning at a press conference at Kendall Station.

The Boston Globe is one sponsor of the service. Mike Sheehan, chief executive officer of the Globe, said Wednesday that the newspaper’s $500,000 in support for late-night T service would be split over several years, and largely consists of marketing agreements and advertising.

“I believe that a world-class city is defined by its transportation system, and a world-class city operates almost 24 hours per day,” Sheehan said.


T officials have said it is unlikely the MBTA will break even on the endeavor. Davey said transportation officials do not expect corporate sponsorships to cover all the costs of the service, and there is little chance that fares from the late-night bus and train rides will cover the cost either.

Instead, Davey said the success of the pilot will be defined in part by the ridership numbers, but also by the feedback the T receives from political and business leaders and the effects the service has in stimulating the late-night commerce that regional officials have been seeking.

The question remains whether the incoming governor and transportation secretary, who will be in charge at this time next year, will be willing to continue the service when the one-year pilot program concludes next March.

“If it’s a successful service, I can’t imagine that any new secretary would seek to take the service away,” Davey said. “But our customers have to vote with their feet.”

For those who use the service, the fare system will stay the same, for now, allowing people to use their monthly passes for entry. If the service survives beyond next March, Davey said, there is a possibility that the T may institute special late-night fares.

Under the extended hours, the subway trains, Green Line trolleys, Silver Line buses, The Ride service for people with disabilities, and the most popular bus routes — numbers 1, 15, 22, 23, 28, 32, 39, 57, 66, 71, 73, 77, 111, 116, and 117 — will continue operating until 3 a.m. Saturday and Sunday mornings.


However, T managers have warned that does not mean that revelers will be able to catch a ride home at 2:59 a.m. The last trains on the schedule will probably converge in the heart of the city at about 2:30 a.m., accommodating those who need to make transfers, before heading out to conclude their run.

One of the most significant challenges to instituting later weekend hours, Davey said, was finding people willing to operate the trains and buses later into the night and negotiating agreements with unions to accommodate extended work hours.

“We couldn’t implement this service by edict,” Davey said. “We had to work with our partners, especially those in [Boston Carmen’s Union Local] 589.”

Davey said that requirements for the amount of rest employees must receive between shifts prevent the T from simply tacking on two hours at the end of each worker’s weekend shift.

Much of the staff who will be operating the late-night shifts are new. At a Wednesday meeting of the Transportation Department board of directors, MBTA chief financial officer Jonathan R. Davis said the service required 133 new recruits, most of whom have been hired and are in training.

“For some of our more senior employees, working until three or four in the morning is not exactly an attractive proposition,” Davey said.


Though the T’s Night Owl service in 2001 was also greeted with great enthusiasm, officials said ridership on that service, which relied on buses only, did not justify the costs.

“When we tried it and failed 10 years ago, that really discouraged from trying to do something like that again,” Davey said.

Since then, some transit specialists have blamed the Night Owl’s modest ridership numbers on passengers’ reluctance to switch to unfamiliar bus routes late at night. They wondered whether the service might be more popular now, when smart phones allow people to track buses in real time, or whether conducting late-night service on regular subway trains, rather than buses, would entice more passengers.

Davey said he believes both those factors will be helpful in making this version of after-hours service a success, as will the countdown clocks now found at all Red, Orange, and Blue line T stops. With a visible indication of how long people can expect to wait for the next train, riders may resist the temptation to instead hop into a cab.

“The anxiety of waiting is significantly reduced,” Davey said.

Martine Powers can be reached at martine.powers@globe.com.