111 (MBTA bus)

Massachusetts Bay Transportation Authority Key Bus Routes

Company type	Public transit service classification
Industry	Public transportation
Founded	2004
Headquarters	Boston , United States
Area served	Boston metropolitan area
Products	Bus transit services on primary corridors
Website	www.mbta.com

Primary bus corridors within the Massachusetts Bay Transportation Authority (MBTA) network consisted of 15 routes characterized by both high passenger volumes and frequent service, as defined in the 2004 MBTA Service Policy. Collectively, these routes represented approximately 40% of the MBTA's total bus ridership. They served critical areas within Boston’s most densely populated neighborhoods and provided vital connections to other MBTA modes, enabling broader regional accessibility.

These routes formed a crucial component of the MBTA’s core transit framework and were prominently displayed on updated transit maps found in subway stations and public venues alongside rapid transit rail, bus rapid transit, and commuter rail lines. This classification supported targeted service enhancements, including experimental late-night operations, and attracted attention from urban planners and transportation engineers. The ongoing 2024 Bus Network Redesign initiative is gradually replacing the "key bus route" designation with a more inclusive high-frequency network concept.

History

In November 2006, the MBTA began initiatives aimed at improving service quality on these primary bus corridors. The 2008 Service Plan advocated for enhancements across multiple lines, notably recommending that route 31 be elevated to key route status. Subsequently, a $10 million Key Routes Improvement Project was launched, partly financed by funds from the American Recovery and Reinvestment Act of 2009. Although Silver Line services were initially included in this effort, they were later managed separately. The project concluded in 2013 without completing all planned upgrades. By June 2017, service reliability on key routes demonstrated a 75% adherence to scheduled frequencies compared to 61% for other routes.

A 2012 study revealed that areas near key bus routes experienced reduced taxi trip generation, suggesting that these frequent services effectively competed with taxi usage where viable alternatives existed.

In April 2014, a one-year pilot extended late-night operations on key bus and rapid transit lines contingent on ridership levels and sponsorship support. However, by April 2015, late-night hours were scaled back on several routes and ultimately discontinued entirely in March 2016.

Key bus routes played a significant role in Boston mayor Marty Walsh’s "Go Boston 2030" plan, which aimed to ensure every residence lies within a ten-minute walk of either a T station or a key bus stop. One proposed new key route sought to link the Longwood Medical and Academic Area with JFK/UMass station via Roxbury.

In May 2022, the MBTA unveiled a draft Bus Network Redesign proposal suggesting modifications to most key routes while upgrading select corridors to establish a high-frequency network that complements rapid transit services. An updated version of this plan was released in November 2022.

Criteria for key routes

The MBTA’s Service Delivery Policy identifies five factors for classifying Key Bus Routes:

• Elevated ridership demand
• Integration within the transit system
• Broad geographic coverage
• Support for significant new developments
• Operation as bus rapid transit

Service standards

Key routes are required to meet more rigorous benchmarks than local routes concerning service span and frequency. The following tables illustrate these distinctions.

Route Category	Minimum Service Span
Local	Weekdays	7:00 AM – 6:30 PM
	Saturdays	8:00 AM – 6:30 PM
	Sundays	10:00 AM – 6:30 PM
Key	Weekdays	6:00 AM – Midnight
	Saturdays	6:00 AM – Midnight
	Sundays	7:00 AM – Midnight

Route Category	Minimum Service Frequency
Local	Morning & Evening Peak	Every 30 minutes
	Other Times	Every 60 minutes
	Weekends	Every 60 minutes
Key	Morning & Evening Peak	Every 10 minutes
	Midday Periods	Every 15 minutes
	Evenings & Weekends	Every 20 minutes

Route list

The MBTA designated 15 primary routes: 1, 15, 22, 23, 28, 32, 39, 57, 66, 71, 73, 77, 111, 116, and 117. These corridors have been targeted for requests to introduce limited-stop or express services aimed at boosting operational efficiency and accommodating high passenger volumes.

1

The 1 Harvard Square–Nubian Station line connects Cambridge to Roxbury. It originated in September 1962 by consolidating the former 76 Harvard–Massachusetts station and 47 Massachusetts station–Dudley routes. In May 1987, the alignment shifted from Washington Street to Albany Street and Melnea Cass Boulevard to provide access to Boston Medical Center. This route mainly follows Massachusetts Avenue, traveling from Harvard past the Massachusetts Institute of Technology, crossing the Charles River via the Harvard Bridge, passing near the Berklee College of Music in Boston, then heading southwest toward Nubian station along Albany Street and Melnea Cass Boulevard.

By 2015, Cambridge had plans to implement signal priority at certain intersections to enhance route performance. The network proposals released in 2022 did not suggest any modifications to this service.

In October 2023, the transit advocacy organization Transitmatters identified the 1 bus as the MBTA’s slowest and most congested line, reporting an average speed of just 6.55 mph and a bunching rate of 17.7%, highlighting considerable operational difficulties impacting reliability.

15

The 15 Fields Corner Station or St. Peter's Square–Ruggles Station route starts at St. Peter's Square in Dorchester, proceeds north on Bowdoin Street, then west along Hancock Street, and north on Columbia Street reaching Uphams Corner. It continues westward on Dudley Street to Nubian station, then heads west on Malcolm X Boulevard before turning north onto Tremont Street toward Ruggles station. During nights and weekends, service ends at Fields Corner station, running via Geneva Avenue and Bowdoin Street back to St. Peter's Square.

On April 6, 1962, buses replaced the former trackless trolleys on the 15 Kane Square–Dudley route. Following the Orange Line’s relocation to the Southwest Corridor in May 1987, this route was extended to reach Ruggles. Service to Kane Square was slightly extended to St. Peter's Square as of August 25, 2024.

The draft network plan from May 2022 recommended extending this line westward to Oak Square, replacing route , thereby creating an Oak Square–Fields Corner corridor. However, by November 2022 the plan reverted to terminating it at Ruggles and maintaining route 65 as a separate service.

22

The 22 Ashmont Station–Ruggles Station via Talbot Ave operates from Ashmont northwestward toward the former site of Egleston station, then continues north along Columbus Avenue and Tremont Street, running roughly parallel to the Orange Line before concluding at Ruggles.

On April 6, 1962, buses replaced the previous trackless trolleys on this corridor as the 22 Ashmont–Dudley via Talbot and Warren. This version differed from earlier routing by extending further north along Warren Street to . The route was lengthened to reach Ruggles in May 1987 coinciding with the Orange Line’s relocation. Draft proposals from May and November 2022 suggested relocating the inner terminal to Longwood Medical Area.

23

The 23 Ashmont Station–Ruggles Station via Washington Street route shares its start and end points with route 22 but follows a distinct course. Departing from Ashmont, it proceeds along Talbot Avenue, then heads north on Washington Street, continuing onto Warren Street until reaching Nubian station. From Nubian, the line travels west on Malcolm X Boulevard to Roxbury Crossing, then moves north via Tremont Street to arrive at Ruggles station.

On April 7, 1962, buses replaced the trackless trolleys operating on the Ashmont–Dudley route that ran via Washington Street and Warren Street. The route was extended to Ruggles in May 1987 following the Orange Line realignment.

A study conducted in 2017 identified overcrowding issues on routes 23 and 28 and recommended lengthening route 29 alongside increasing its frequency. Beginning March 1, 2022, a city-funded fare-free initiative covers routes 23, 28, and 29 through February 28, 2026. No modifications affecting route 23 were proposed in the transit network plans released in May or November of 2022.

28

The 28 Mattapan Station–Ruggles Station line serves the Mattapan and Grove Hall neighborhoods by running along Blue Hill Avenue, a key arterial corridor. Historically significant as a heavily trafficked trunk route, Blue Hill Avenue saw route 29 Mattapan–Egleston operating at intervals as short as 1.5 minutes during morning peak periods in 1945. Streetcar service operated on a dedicated right-of-way here until buses replaced them in 1955. Introduced in 1987 to supplement route 29, route 28 became the principal service along Blue Hill Avenue by 1989, with route 29 limited to rush hour and shorter trips. Some stops received shelters starting in 2001. Between 2006 and 2010, a short-turn peak period service ran as route 25 between Franklin Park and Dudley (later Ruggles).

The 2003 Program for Mass Transportation explored multiple expansions of the Silver Line, including a bus rapid transit (BRT) overlay for route 28 revived in the Silver Line Phase III plans of 2006. In 2009, a $114 million limited-stop BRT service named 28X was proposed for this corridor—the busiest bus corridor in New England—with plans for dedicated lanes and queue jump lanes. Construction was scheduled to begin in April 2010 aiming for service commencement in early 2012.

However, local opposition arose quickly due to insufficient community engagement, concerns over parking loss, removal of median strips, and extended construction disruptions. As a result, the state withdrew the project by late 2009. In June 2010, the MBTA introduced longer, 60-foot buses on route 28 to boost capacity; this change faced resistance from some residents due to stop eliminations required for accommodating larger vehicles. The Roxbury–Dorchester–Mattapan Transit Needs Study of 2012 recommended implementing the proposed express bus service (28X) without new infrastructure investments.

In August 2020, the MBTA and City of Boston applied for $15 million in federal funds toward a $30 million Blue Hill Avenue improvement project featuring center-running bus lanes with an anticipated completion by late 2021; however, this funding request was denied in September. A subsequent $25 million application was submitted in July 2021. A city-sponsored pilot program offered fare-free rides and all-door boarding on route 28 from August 2021 through February 2022 to improve travel times on this frequently delayed line. Following this pilot, fare-free service on routes 23, 28, and 29 was extended from March 2022 through February 2026. Additionally, Boston secured a $15 million federal grant toward reconstructing Blue Hill Avenue in November 2021.

Transit network proposals released in May and November of 2022 suggested extending route 28 beyond Roxbury Crossing through Longwood Medical Area while eliminating the segment between Roxbury Crossing and Ruggles. In February 2024, Boston announced plans for a $44 million Blue Hill Avenue reconstruction project—including center-running bus lanes—with construction expected to commence in 2026.

32

The 32 Wolcott or Cleary Square–Forest Hills Station line operates along Hyde Park Avenue, connecting Forest Hills to Readville and serving the neighborhoods of Jamaica Plain, Roslindale, and Hyde Park. This route runs parallel to the commuter rail tracks between Forest Hills and Readville.

Prior to 1953, Route 32 functioned as a trolley service from Forest Hills to Cleary Square before transitioning to trackless trolley operations. By 1958, diesel buses had replaced trackless trolleys on segments south of Forest Hills. The trackless trolley turnaround loop was situated at the intersection of Hyde Park Avenue and Pine Street.

In 1981, Route 31, which ran from Mattapan Square to Wolcott Square, was combined with Route 32 at Cleary Square, creating the current Route 32 Forest Hills–Wolcott Square. Additionally, Route 50 was adjusted to provide access to Malone Elderly Housing via River Street, Gordon Avenue, Summer Street (inbound), and Austin Street (outbound). The May and November 2022 network proposals did not include modifications for this route.

39

The 39 Forest Hills Station–Back Bay Station route was introduced in December 1985 as a replacement for the Green Line E branch service between Heath Street and Arborway; initially classified as "temporary" until 2011. It parallels the Green Line from Heath Street to Copley and offers connections to both the Orange Line and commuter rail at either end, including Amtrak services at Back Bay.

Route 39 was notable for being the MBTA's first route to regularly deploy articulated buses—a practice later adopted by other routes such as the 28 in late 2005. By 2013, it ranked as Boston’s second busiest bus line. Its high passenger volumes contributed to the expansion of Forest Hills station during the Casey Arborway reconstruction.

The May 2022 draft network plan suggested extending Route 39 through and , replacing segments of routes , , and , while eliminating service between Longwood Avenue and Back Bay. However, the November 2022 draft reverted Route 39 to its existing alignment and proposed increasing frequency on Route 47 with an extension to Union Square.

57

The 57 Watertown Yard–Kenmore Station route connects Boston, Newton, and Watertown, succeeding the former Green Line A branch which ceased operations in 1969. Historically one of Boston's limited-stop services—prohibiting pickups along Commonwealth Avenue between Packard's Corner and Kenmore Square—this restriction was discontinued in December 2006. No alterations were recommended for this route in either the May or November 2022 network plans.

66

The 66 Harvard Square–Nubian Station via Allston line, once operated as a trolley, originates at Nubian Square in Roxbury and crosses Southwest Corridor Park near Roxbury Crossing. It briefly shares alignment with Route 39 and the Green Line E branch from Brigham Circle up to Boston’s city boundary. Traveling through Brookline and Allston along Harvard Street, it detours via Union Square (Allston) before proceeding along Cambridge Street and North Harvard Street to conclude at Harvard Square in Cambridge. This route facilitates transfers among several transit lines including the Silver Line at Nubian, Orange Line at Roxbury Crossing, multiple Green Line branches (E, D, C, B), and the Red Line at Harvard. The May and November 2022 network drafts proposed no changes for this service. In August 2024, northbound buses were redirected through the Harvard Bus Tunnel.

71

The 71 Watertown Square–Harvard station route originates at the lower level of the Harvard bus tunnel, then proceeds southward onto Mount Auburn Street before heading west into Watertown, where it concludes at Watertown Square.

At Harvard, buses complete their turnaround by leaving the tunnel and navigating a sequence of turns along Massachusetts Avenue, Garden Street, and Waterhouse Street before returning to the tunnel. In Watertown, a dedicated loop on private right-of-way allows for vehicle turning and passenger boarding.

Streetcar operations ceased on September 4, 1958, with trackless trolley service continuing until March 13, 2022. The year 2017 saw routes 71 and 73 incorporated into a bus rapid transit pilot initiative.

Routes 71 and 73, alongside neighboring routes , were among the final MBTA lines to operate trolleybuses ("trackless trolleys"), reflecting Boston’s historic transit legacy. These routes fully transitioned to diesel buses in March 2022. While no modifications were suggested in the 2022 network proposals, Watertown plans a modest extension to Watertown Yard as part of a redesign of the square.

73

The 73 Waverley Square–Harvard Station route begins within the Harvard bus tunnel and shares the Mount Auburn Street corridor with route 71 through Cambridge and Watertown. It then diverges onto Belmont Street, which borders Belmont and Watertown, continuing along Trapelo Road to terminate at Waverley Square. The route completes a loop at the Waverley commuter rail station on the Fitchburg Line.

Initially served by streetcars until the 1950s, route 73 fully converted to trackless trolley operation in 1958 following the introduction of short-turn service in 1957. Trackless trolleys remained in use until March 13, 2022. The May and November 2022 network plans did not propose any changes to this route.

77

The 77 Arlington Heights–Harvard Station line connects Arlington with Harvard station via Massachusetts Avenue. Prior to the Red Line Northwest Extension during the 1980s, routes 77 and 77A were the main transit services northwest of Harvard, with combined streetcar frequencies under one minute during peak periods in 1945. Route 77 transitioned to diesel buses in 1955; meanwhile, route 77A adopted trolleybus operation in 1958 to free up streetcars for conversion of the Green Line D branch and to eliminate boarding islands for improved automobile traffic flow. Route 77A provided local stops south of the carhouse while route 77 operated as a limited-stop service. Between 1998 and 2005, route 77 gradually replaced route 77A service, which was completely discontinued by 2022. In 2017, Arlington pursued a private grant aimed at implementing signal priority, queue jump lanes, and potential dedicated bus lanes along its segment. No adjustments were proposed for this route in either the May or November 2022 network plans.

111

The 111 Woodlawn–Haymarket Station line connects downtown Boston with Chelsea via the Bill Russell and Tobin Bridges. Originally run as streetcars between Chelsea Square and Woodlawn under Boston Elevated Railway management in 1936, it was converted that October to a bus extension of the City Square–Chelsea Square route. The line was extended to Haymarket in April 1975 following closure of the Charlestown Elevated; partial extensions beyond Woodlawn occurred beginning January 2001. Service beyond Woodlawn was discontinued in September 2019; Cary Square short-turn trips were replaced by Woodlawn trips in December 2021. The 111 remains one of MBTA's highest-frequency routes, operating every five minutes during peak hours. No changes were included for this line in the May or November 2022 network proposals.

116/117

The 116 Wonderland Station–Maverick Station via Revere Street and 117 Wonderland Station–Maverick Station via Beach Street routes provided service to East Boston, Chelsea, and Revere. These two lines followed largely the same course through East Boston and Revere, with their only divergence occurring near Wonderland. According to the network proposals from May and November 2022, route 117 was planned for elimination, with the portion between Broadway and Wonderland incorporated into an extended route to maintain essential bus frequency. This adjustment was implemented on December 15, 2024.

See also

• List of MBTA bus routes
• MBTA crosstown bus routes
• MBTA Silver Line (previously included in key routes)
• Free public transport in Boston

External links

• MBTA – routes , , , , , , , , , , , , , ,
• MBTA - Key Bus Route Improvement Program