The MBTA Green Line core shutdown began Saturday, September 26, 2026, closing the downtown trunk of all four branches through October 4 so crews can replace century-old tunnel signals and prepare stations for new Type 10 trains.
In a September 24 reminder, the T said nine consecutive days of 24/7 access let it finish signal work deferred for decades while piggybacking station, power, and platform upgrades. Riders should budget at least 20–25 extra minutes and lean on free shuttles plus the Orange Line.
What the MBTA Green Line Core Shutdown Covers
From Sept. 26 through Oct. 4, Green Line service is suspended between Babcock Street and Government Center on the B branch, Kenmore and Government Center on the C, Kenmore and North Station on the D, and Heath Street and North Station on the E, according to the MBTA. Truncated outer segments keep running: B between Boston College and Babcock, C and D west of Kenmore, and E between North Station and Medford/Tufts on the GLX side.
The agency says today’s signals date to the late 1800s—the same era as North America’s first electric trolleys—and that modern train detection, congestion management, and spacing are the foundation for more reliable headways once the project is done. The work also aligns with Type 10 cars expected to arrive next year, including platform-edge and catenary adjustments for the larger fleet.
Shuttles, Free Fares, and Orange Line Detours
Free accessible shuttles run Babcock–Back Bay for B riders and Kenmore–Back Bay for C and D riders, with transfers to the Orange Line at Back Bay toward downtown and North Station. On the E branch, the Route 39 bus—boosted with extra trips—replaces Heath-to-Back Bay service and is fare-free for the diversion. Routes 57 and surface stops west of Kenmore are also fare-free, and Kenmore fare gates are open.
There is no dedicated shuttle for downtown trunk stops between Copley and North Station; the T directs those riders to nearby Orange Line stations such as Back Bay, Downtown Crossing, State, and Haymarket. Accessible vans are available between Kenmore and North Station via station staff or call boxes. The diversion follows a similar multi-day outage earlier this year and overlaps other Green Line modernization work detailed by StreetsblogMASS and local outlets.
Why the T Chose a Nine-Day Closure
MBTA officials argue overnight windows cannot deliver the tunnel access needed for signal replacement, and single-weekend outages would be slower and more expensive. Around-the-clock closures let multiple contractors and in-house crews stack Park Street track reconstruction, Symphony station work, radio cable installs, power inspections, and station “brightening” between Kenmore and North Station.
Commuters juggling other T policy changes—including bus lane camera fines starting Oct. 1 and free fares for car-free seniors on Oct. 13—should treat the Green Line trunk as offline through Oct. 4 and watch T-Alerts. For ongoing transit safety context on surface routes, see our recent report on the No. 28 Mattapan bus fight under Transit Police review.