A southbound street-level stop for the SL5 route of the bus rapid transit Silver Line is outside fare control.

The tight radius of curvature of the track frequently causes loud squealing noises to emit from the train wheels, which are audible at street level near the station entrance at the corner.

The MBTA also retrofitted flange stick lubricators on newer trains, which scrape graphite onto the side of the wheel and do not affect braking.

[3] However in 2018, journalism students from adjacent Emerson College measured sound intensities over 110 dBA in the station.

[5] Boylston and Park Street were built with rectangular stone headhouses designed by Edmund M. Wheelwright that did not aesthetically match the Common.

[17]: 171  In 1964, the Tremont Street subway, including Boylston station, was designated a National Historic Landmark.

[16]: 22  A planned renovation in 1986 was deferred due to the station's historic status, though the disused outer tracks were fenced off.

[19] In mid-2006, the MBTA installed brighter lighting at Boylston station, as well as modern electronic faregates and fare vending machines for the CharlieCard system.

[21]: 25  Silver Line service on the surface, running on Tremont Street, began stopping at Boylston in December 2001.

[23] In 2019, the MBTA indicated that Boylston was a "Tier II" accessibility priority pending the results of conceptual design.

[24] A few months before the station opened, there was a gas explosion at the corner of Tremont and Boylston Streets on March 4, 1897.

[26] The origin of the explosion was deemed to be the short-circuiting of the overhead lines in the station, which began to burn and catch fire.