86 (MBTA bus)

Route 86

Company type	Bus route
Industry	Public transportation
Founded	1925
Founder	Massachusetts Bay Transportation Authority (MBTA)
Headquarters	Boston and Cambridge , United States
Area served	Boston and Cambridge, Massachusetts
Products	Bus service between Reservoir station and Harvard station
Owner	Massachusetts Bay Transportation Authority (MBTA)
Website	mbta.com/schedules/86

Route 86 is a bus line serving the Boston and Cambridge areas, managed by the Massachusetts Bay Transportation Authority (MBTA) within its MBTA bus network. The service links Reservoir station to Harvard station, passing through Lower Allston and Brighton Center. In 2018, it was ranked 18th in weekday ridership but only 37th by number of trips. Despite its substantial passenger volumes and importance as a crosstown connector, a 2018–19 MBTA assessment found the route’s service to be infrequent and unreliable.

The route’s history dates back to horsecar operations in the 19th century, which were subsequently upgraded to electric streetcars. Between 1925 and 1931, three overlapping bus routes—later designated as 63, 86, and —replaced circumferential streetcar lines and introduced new linkages. Originally, Route 86 operated between Union Square in Allston and Union Square in Somerville, later extending to Sullivan Square in 1977 and further to supplement route 91 in 1981. The western terminus expanded to Cleveland Circle in 1989, taking over from route 63. In December 2024, the eastern portion was reassigned to route , truncating Route 86 to run solely between Reservoir and Harvard stations.

Route

Route 86 provides transit between Harvard station in Cambridge and Reservoir station near Cleveland Circle, tracing the boundary between Brookline and Brighton. Buses heading toward Reservoir depart from Massachusetts Avenue near Garden Street, while those bound for Harvard conclude their trips within the Harvard Bus Tunnel. The path follows John F. Kennedy Street/North Harvard Street southward to Barry's Corner, then proceeds west along Western Avenue before turning south on Leo M. Birmingham Parkway and Market Street to reach Brighton Center. From there, it continues south along Chestnut Hill Avenue to the Reservoir station busway.

Trip durations typically take around 20 minutes off-peak and can extend up to 30 minutes during rush hours, with shorter travel times during early mornings and late nights. Service operates roughly from 5:00 am until 12:30 am on weekdays and Saturdays, starting around 6:00 am on Sundays. Beginning December 2024, peak weekday intervals are at least every 15 minutes; midday buses arrive every 20 minutes; evenings and weekend frequencies are approximately every 25 minutes. As a circumferential route providing crosstown connections, it links with subway lines at (Red Line), (Green Line B branch), (Green Line C branch), and Reservoir (Green Line D branch).

Operating with standard local fares, Route 86 recorded an average of 6,150 weekday boardings in 2018 under its previous Reservoir-to-Sullivan configuration. Weekend ridership averaged about 3,040 on Saturdays and roughly 1,840 on Sundays. This ridership level exceeded that of four major MBTA bus routes but was accompanied by low frequency service that led to overcrowding.

Early lines

Portions of today’s Route 86 originated as horsecar and streetcar corridors:

• The Chestnut Hill Avenue segment between Beacon Street and Commonwealth Avenue opened in 1896 as an extension of the electric Beacon Street line. Although revenue service ceased in 1926, the tracks remain for non-revenue movements.
• The stretch from Harvard Square to Union Square in Brighton began as horsecar lines operated by the Cambridge Railroad. The sections along Western Avenue and Market Street opened in 1880 from Central Square, Cambridge, with electrification completed by 1896. The North Harvard Street portion opened in 1883 but was never electrified and was abandoned by the early 1890s.
• The former Kirkland Street segment between Harvard Square and Beacon Street (now part of route 109) was initially a horsecar line run by the Charles River Street Railway starting in 1882; it never saw electrification and was discontinued in the early 1890s.
• The section connecting Sullivan Square and Union Square in Somerville (now included in route 109) originated as a horsecar line under the Somerville Horse Railroad (later Middlesex Railroad) beginning in 1858. Electric service commenced on October 17, 1895; early streetcars used a detour to bypass a grade crossing near Sullivan Square until a bridge replaced it by 1901.

Bus Substitutions

During the 1880s, horsecar and streetcar services in Boston and its surrounding areas were unified under the West End Street Railway, which was subsequently leased by the Boston Elevated Railway (BERy) in 1897. The BERy initiated bus operations in 1922. On August 22, 1925, a bus line connecting Harvard Square and Union Square in Somerville was launched, later extended to Union Square, Allston on December 19.

By 1930, the section between Union Square and Sullivan Square functioned as part of a streetcar route running from Central Square to Sullivan Square. On February 1 of that year, the segment from Central Square to Union Square was replaced by a bus service, leaving a streetcar shuttle operating between Union Square and Sullivan Square. Subsequently, on November 15, at the city's request aimed at easing congestion in Union Square, this shuttle was substituted with a new bus route. These two bus routes were consolidated into a single Central Square–Sullivan Square line on February 14, 1931. The tracks between Sullivan and Union Squares were retained for non-revenue operations until 1951.

On June 8, 1931, buses replaced the streetcars on the Brighton Center–Central Square line, which was also extended southward to Commonwealth Avenue. Initially, only half of this service continued south beyond Brighton Center. The Western Avenue tracks remained operational until 1950 for Watertown service, which is now served by bus route .

Subsequent Developments

Between 1940 and 1941, BERy updated its public numbering system: the Commonwealth Avenue–Central Square line became route 63; Union Square–Union Square was designated route 86; and Central Square–Sullivan Square was assigned route 91. Due to wartime restrictions in 1943, the Western Avenue portion of route 63 was suspended but resumed in 1946 as a Cleveland Circle–Central Square service.

In 1947, the Metropolitan Transit Authority (MTA) succeeded BERy. Sunday operations on route 63 ceased in 1958. The southern endpoint of this route was extended from Cleveland Circle to a new busway at Reservoir station in 1959 coinciding with the opening of the Riverside Line. In an experimental move during 1962, routes were interlined: route 63 paired with route 83 and route 91 with route 93; however, these changes were reversed by the mid-1960s due to limited effectiveness.

The MTA transitioned into the Massachusetts Bay Transportation Authority (MBTA) in 1964. In 1973, Sunday service combining routes 63, 64, and 86 commenced between Union Square and Cleveland Circle. Route 86 extended peak hour trips to Sullivan Square in 1977 to complement route 91. Sunday service ended in 1981; nevertheless, off-peak and Saturday runs on route 86 were expanded to Sullivan Square. By the early 1980s, weekday evening and Saturday morning services for routes 63 and 64 were merged into a loop operation that included Sundays starting in 1983.

Route changes continued with the discontinuation of route 63 in December 1989; simultaneously, route 86 was realigned into a circumferential line running between Cleveland Circle and Sullivan Square. Route 66 took over service from Union Square to Harvard Square covering part of the former route segment while route 70 operated along what had been the eastern portion of route 63. From December 1990 until December 1993, a midday variant of route 64 ran between Cleveland Circle and Central Square responding to concerns from elderly passengers.

During the 1990s, short-turn peak-hour trips were added on route 86. In September 2000, limited-stop crosstown service CT2 was extended to Sullivan Square to supplement routes serving between Union Square and Sullivan Square. Eastbound buses began using the Harvard Bus Tunnel starting September 2008. Most peak-hour short-turn trips were discontinued by September of 2011. Between April 2019 and May 2020, route 86 experienced detours due to bridge reconstruction along the Lowell Line connected with Green Line Extension work.

A review conducted by MBTA during 2018–19 identified that despite high ridership levels and its critical role as a crosstown connector, route 86 suffered from infrequent and unreliable service; no immediate routing adjustments were recommended. By the year 2022, improvements had been made leading to better scheduled headways.

In May 2022, MBTA’s draft plan for a systemwide redesign proposed truncating route 86 to operate only between Harvard and Reservoir stations while extending higher-frequency service on route 109 along the Harvard–Sullivan segment. A revision released in November confirmed these proposals with implementation slated for December 15, 2024; these changes will enhance frequency on both routes.