28 (MBTA bus)

Massachusetts Bay Transportation Authority Primary Bus Corridors

Company type	Public transit service category
Industry	Public transportation
Founded	2004
Area served	Boston, Massachusetts metropolitan area
Products	Bus transit services on key routes

Primary bus corridors of the Massachusetts Bay Transportation Authority (MBTA) consisted of 15 routes characterized by high passenger volumes and frequent service, as outlined in the 2004 MBTA Service Policy. Collectively, these routes represented approximately 40% of the MBTA’s overall bus ridership. They played a crucial role in serving Boston’s most densely populated neighborhoods and provided vital connections to other MBTA transit modes, thereby facilitating regional mobility.

Acknowledged as the core framework of MBTA’s bus operations, these primary routes were prominently displayed on updated standard transit maps alongside rapid transit lines, bus rapid transit corridors, and commuter rail services. They were given precedence for enhancements such as experimental late-night operations and have been integral to urban development initiatives and transportation planning research. With the implementation of the MBTA Bus Network Redesign in 2024, the specific "primary bus corridor" classification is being phased out in favor of a broader high-frequency route system.

History

The MBTA launched an initiative in November 2006 aimed at elevating service standards on its primary bus corridors. The 2008 Service Plan advocated for improvements including the promotion of Route 31 to primary corridor status. Subsequently, a $10 million Key Routes Improvement Project was financed through the American Recovery and Reinvestment Act of 2009. Although initially incorporated, the Silver Line was later excluded from this program. The project concluded in 2013, with some planned enhancements remaining incomplete. By June 2017, service reliability on these primary corridors was superior to other routes, achieving on-time performance rates of 75% compared to 61%.

A study conducted in 2012 demonstrated that areas near primary bus corridors experienced a decline in taxicab trip generation, underscoring their competitive edge among frequent service routes.

In April 2014, a pilot program introduced extended late-night operations on both primary bus corridors and rapid transit lines, subject to ridership levels and external sponsorships. However, by April 2015, late-night service hours were reduced on several primary routes, with all such late-night services discontinued by March 2016.

Primary bus corridors were highlighted within Boston Mayor Marty Walsh’s “Go Boston 2030” initiative, which sought to ensure that every residence was within a ten-minute walk of either a T station or a primary route stop. The plan also proposed a new primary route linking Longwood Medical Area to JFK/UMass via Roxbury.

In May 2022, the MBTA unveiled a draft redesign affecting most primary corridors while elevating certain routes into a high-frequency network designed to complement rapid transit services. An updated version of this plan was released in November 2022.

Criteria for Key Routes

The MBTA's Service Delivery Policy designates Key Bus Routes according to five main factors:

• Elevated passenger demand
• Integration within the transit network
• Broad geographic reach
• Facilitation of significant new development projects
• Functioning as bus rapid transit

Service Standards

Compared to regular local routes, Key Bus Routes are required to adhere to higher benchmarks regarding both service hours and frequency.

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	Peak hours (AM & PM)	Every 30 minutes
	Off-peak hours	Every 60 minutes
	Weekends (Saturday & Sunday)	Every 60 minutes
Key	Peak hours (AM & PM)	Every 10 minutes
	Midday periods	Every 15 minutes
	Evenings and weekends	Every 20 minutes

List of Routes

The MBTA has classified fifteen routes as key: 1, 15, 22, 23, 28, 32, 39, 57, 66, 71, 73, 77, 111, 116, and 117. These lines have seen demands from both public officials and riders for limited-stop or express options aimed at enhancing efficiency and accommodating substantial ridership.

1

The 1 Harvard Square–Nubian Station route connects Cambridge with Roxbury, Boston, having been formed in September 1962 through the consolidation of the former 76 Harvard–Massachusetts station route and the 47 Massachusetts station–Dudley line. In May 1987, its alignment shifted from Washington Street to Albany Street and Melnea Cass Boulevard to provide service to Boston Medical Center. The route largely travels along Massachusetts Avenue, departing from Harvard, passing the Massachusetts Institute of Technology, crossing the Charles River via the Harvard Bridge, continuing through Boston near the Berklee College of Music to Boston Medical Center, then proceeding southwest toward Nubian station using Albany Street and Melnea Cass Boulevard.

By 2015, Cambridge had plans to introduce signal priority at selected intersections on route 1 to enhance transit movement. No alterations to this route were proposed in the network plans released in May and November of 2022.

In October 2023, the transit advocacy organization Transitmatters identified the number 1 bus as the slowest and most prone to bus bunching within the MBTA system, reporting an average speed of just 6.55 mph and a bunching occurrence rate of 17.7%, highlighting operational challenges that impact its dependability.

15

The 15 Fields Corner Station or St. Peter's Square–Ruggles Station line operates from St. Peter's Square (also known as Coppens Square) in northern Dorchester, proceeding north along Bowdoin Street, turning west onto Hancock Street, then continuing north on Columbia Street toward Uphams Corner. From there, it heads west via Dudley Street to Nubian station, then travels west on Malcolm X Boulevard before turning north on Tremont Street to reach Ruggles station. During nights and weekends, service terminates at Fields Corner station, following a route through Geneva Avenue and Bowdoin Street back to St. Peter's Square.

This bus route began service on April 6, 1962, replacing the former trackless trolley system along the 15 Kane Square–Dudley corridor via Uphams Corner and Dudley Street. The route was extended to Ruggles following the Orange Line’s relocation to the Southwest Corridor in May 1987. On August 25, 2024, the Kane Square segment was slightly lengthened to reach St. Peter's Square.

In the May 2022 draft network proposal, plans suggested extending this route westward to Oak Square, effectively replacing route 19 and creating an Oak Square–Fields Corner service line. However, by November 2022, the draft plan reverted to terminating the route at Ruggles, keeping route 65 as a separate service.

22

The 22 Ashmont Station–Ruggles Station via Talbot Ave route runs from Ashmont northwest toward the former location of Egleston station, then heads north along Columbus Avenue and Tremont Street, paralleling the Orange Line before concluding at Ruggles.

Originally operating as the 22 Ashmont–Dudley via Talbot and Warren, this bus service replaced trackless trolleys on April 6, 1962. It extended north along Warren Street to Dudley before being lengthened to Ruggles after the Orange Line’s Southwest Corridor relocation in May 1987. Both the May and November 2022 draft plans proposed shifting its inner terminal to Longwood Medical Area.

23

The 23 Ashmont Station–Ruggles Station via Washington Street shares its endpoints with route 22 but follows a distinct course. Beginning at Ashmont, it travels along Talbot Avenue, then proceeds north on Washington Street and Warren Street to reach Nubian station. From Nubian, it continues west on Malcolm X Boulevard to Roxbury Crossing, then heads north on Tremont Street toward Ruggles station.

This route replaced trackless trolley service on April 7, 1962, initially operating as the 22 Ashmont–Dudley via Washington Street and Warren. It was extended to Ruggles concurrent with the Orange Line’s relocation in May 1987.

A study conducted in 2017 highlighted overcrowding problems affecting routes 23 and 28, recommending both an extension of route 29 and increased service frequency as potential solutions. Additionally, a city-funded fare-free initiative has covered routes 23, 28, and 29 from March 1, 2022 through February 28, 2026. No modifications to this route were included in either the May or November 2022 draft network plans.

28

The 28 Mattapan Station–Ruggles Station line connects the neighborhoods of Grove Hall and Mattapan along Blue Hill Avenue, a major thoroughfare. Historically, Blue Hill Avenue was a prominent transit route; in 1945, route 29 Mattapan–Egleston operated with 1.5-minute intervals during morning peak periods. Streetcars ran on a dedicated right-of-way until buses replaced them in 1955. Introduced in May 1987 to supplement route 29, route 28 became the main service along Blue Hill Avenue by December 1989, while route 29 was limited to rush-hour trips serving Jackson Square. Some stops received shelters in 2001. Between December 2006 and June 2010, a morning peak short-turn service ran as route 25 between Franklin Park and Dudley (later Ruggles).

The 2003 Program for Mass Transportation (PMT) examined various Silver Line expansion options, including a bus rapid transit (BRT) overlay for route 28 that briefly resurfaced in the Silver Line Phase III proposals of 2006. In 2009, the state introduced plans for the 28X, a limited-stop BRT service on this corridor—then the busiest bus route in New England—with intentions for dedicated lanes and queue jump signals. The $114 million initiative aimed to commence construction in April 2010 and launch service by early 2012.

Despite these plans, significant opposition arose due to insufficient community engagement, the removal of parking spaces and median strips, and concerns about extended construction impacts. As a result, the state withdrew the proposal by late 2009. In June 2010, the MBTA deployed longer 60-foot buses on route 28 to boost capacity; however, some stops in the hilly Grove Hall area were eliminated, causing local discontent. A transit study conducted in 2012 recommended introducing the 28X as an express bus without new infrastructure additions.

In August 2020, MBTA and Boston jointly pursued $15 million in federal funds for a $30 million Blue Hill Avenue project featuring center-running bus lanes, targeting completion by the end of 2021; this funding request was denied in September. A subsequent $25 million application was submitted in July 2021. From August 2021 through February 2022, a city-funded pilot tested fare-free rides and all-door boarding on route 28 to enhance travel efficiency. Following this, fare-free service on routes 23, 28, and 29 was extended from March 2022 until February 2026. In November 2021, Boston secured a $15 million federal grant toward the $39.5 million Blue Hill Avenue reconstruction effort.

Network proposals from May and November 2022 suggested extending route 28 beyond Roxbury Crossing through the Longwood Medical Area while eliminating the Roxbury Crossing–Ruggles segment. In February 2024, Boston announced plans for a $44 million reconstruction of Blue Hill Avenue including center bus lanes, with construction anticipated to start in 2026.

32

The 32 Wolcott or Cleary Square–Forest Hills Station line runs along Hyde Park Avenue between Forest Hills and Readville, serving the communities of Jamaica Plain, Roslindale, and Hyde Park while closely following commuter rail tracks throughout its length.

Prior to 1953, Route 32 operated as a trolley line connecting Forest Hills to Cleary Square before transitioning to trackless trolley service. By 1958, diesel buses replaced trackless trolleys south of Forest Hills. The trackless trolley turnaround loop was located at Hyde Park Avenue and Pine Street.

In 1981, Route 31—which ran between Mattapan Square and Wolcott Square—was merged into Route 32 at Cleary Square, creating Route 32 Forest Hills–Wolcott Square. Additionally, Route 50 was rerouted to serve Malone Elderly Housing via River Street, Gordon Avenue, Summer Street (inbound), and Austin Street (outbound). No modifications were proposed for Route 32 in the May or November 2022 network redesign plans.

39

The 39 Forest Hills Station–Back Bay Station line began service in December 1985, taking over the Green Line E branch segment between Heath Street and Arborway. This route runs alongside the Green Line from Heath Street to Copley and offers transfers to the Orange Line and commuter rail at both termini, with Amtrak connections available at Back Bay.

Route 39 was the pioneer MBTA route to consistently deploy articulated buses, a feature that became widespread across the system by late 2005. By 2013, it ranked as Boston’s second most heavily utilized bus line. Its substantial passenger volume was a key factor in the expansion of Forest Hills station during the Casey Arborway redevelopment.

The May 2022 draft of the network redesign suggested extending Route 39 through and , substituting portions of routes , , and , while eliminating service between Longwood Avenue and Back Bay. However, the November 2022 draft restored Route 39 to its current path, enhancing frequency on Route 47, which was proposed to extend to Union Square.

57

The 57 Watertown Yard–Kenmore Station route serves the communities of Boston, Newton, and Watertown. It replaced the discontinued Green Line A branch service in 1969. Previously, it provided limited-stop service along Commonwealth Avenue from Packard's Corner to Kenmore until this was discontinued in December 2006. No modifications to this route were included in either the May or November 2022 network proposals.

66

The 66 Harvard Square–Nubian Station via Allston route, originally operated as a trolley line, connects Nubian Square in Roxbury with Harvard Square in Cambridge. It crosses the Southwest Corridor Park near Roxbury Crossing and shares parts of its path with Route 39 and the Green Line E branch close to Boston’s boundary. Serving neighborhoods such as Brookline and Allston, it detours through Union Square before continuing along Cambridge Street and North Harvard Street. This route links several transit lines including the Silver Line at Nubian, Orange Line at Roxbury Crossing, multiple Green Line branches (E, D, C, B), and Red Line at Harvard. The May and November 2022 network drafts did not propose any changes for this route. In August 2024, northbound trips 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, proceeds south along Mount Auburn Street, then heads westward into Watertown, concluding at Watertown Square.

At Harvard station, buses exit the tunnel and make a series of turns: left onto Massachusetts Avenue, right onto Garden Street, right onto Waterhouse Street, and finally right again on Massachusetts Avenue to re-enter the tunnel. At the Watertown terminus, a dedicated private right-of-way loop facilitates bus turning and passenger boarding.

Streetcar operations on this line ceased on September 4, 1958; trackless trolley service continued until March 13, 2022. In 2017, routes 71 and 73 were selected for participation in a pilot program for bus rapid transit.

Along with routes 73 and others such as , routes 71 was among the final MBTA lines operating trolleybuses ("trackless trolleys") before transitioning fully to diesel buses in March 2022. The May and November 2022 network plans did not recommend any adjustments for this route; nevertheless, Watertown has intentions to extend Route 71 slightly to reach Watertown Yard as part of plans to reconfigure Watertown Square.

73

The 73 Waverley Square–Harvard Station route starts at the Harvard bus tunnel and travels along Mount Auburn Street, sharing its path with route 71 through the cities of Cambridge and Watertown. It then proceeds along Belmont Street, which runs along the boundary between Belmont and Watertown, before continuing on Trapelo Road in Belmont. The route concludes at Waverley Square, completing a loop at the Waverley commuter rail station on the Fitchburg Line.

This corridor was originally served by streetcars until the 1950s. Beginning in 1957, trackless trolleys operated short-turn trips from Harvard to Benton Square and fully replaced streetcars by 1958. Trackless trolley service continued uninterrupted until March 13, 2022. The May and November 2022 network proposals did not include any modifications to this route.

77

The 77 Arlington Heights–Harvard Station line provides transit service between Arlington and Harvard Station via Massachusetts Avenue. Prior to the Northwest Extension of the Red Line in the 1980s, routes 77 and 77A were the primary transit options northwest of Harvard, with streetcar frequencies reaching less than one minute during peak periods in 1945. Route 77 transitioned to diesel buses in 1955, while route 77A converted to trolleybus operation in 1958 to facilitate the Highland branch conversion and eliminate boarding islands used by cars. Route 77A maintained local service south of the carhouse until it was gradually phased out between 1998 and 2005 and was completely discontinued in 2022. In 2017, Arlington pursued private funding to implement signal priority, queue jump lanes, and potential bus-only lanes on its portion of the corridor. The May and November 2022 network plans did not propose any changes to this route.

111

The 111 Woodlawn–Haymarket Station route links downtown Boston with sections of Chelsea by crossing the Bill Russell and Tobin Bridges. Originally established as a streetcar line connecting Chelsea Square and Woodlawn, it was acquired by Boston Elevated Railway in 1936 and replaced with bus service later that same year. In April 1975, service was extended to Haymarket following the closure of the Charlestown Elevated; a partial extension beyond Woodlawn occurred in January 2001. Service beyond Woodlawn ended in September 2019, with Cary Square short-turn trips replaced by Woodlawn trips as of December 2021.

The 111 stands out as one of MBTA’s highest-frequency numbered bus routes, operating at five-minute intervals during rush hours. No adjustments were recommended for this route in either 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 served East Boston, Chelsea, and Revere areas. Both routes shared most of their alignment through East Boston and Revere but diverged near Wonderland. The network plans released in May and November 2022 proposed eliminating route 117, with its segment between Broadway and Wonderland station being incorporated into an extended route , operating at increased frequency. This modification was implemented on December 15, 2024.

See also

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

External links

• MBTA – lines , , , , , , , , , , , , , ,
• MBTA – Major Bus Route Enhancement Initiative