As of 1 July 2019, all subway trips (Green Line, Blue Line, Orange Line, Red Line, Ashmont-Mattapan Line, and the Waterfront section of the Silver Line) cost $2.40 for CharlieCard holders and $2.90 for CharlieTicket or cash payers.
Local bus and trackless trolley fares (including the Washington Street section of the Silver Line) are $1.70 for CharlieCard holders and $2.00 for others.
All transfers between subway lines are free with all fare media.
Passengers using CharlieCards can transfer free from a subway to a bus, and from a bus to a subway for the difference in price ("step-up fare").
CharlieTicket holders can transfer free between buses, but not between subway and bus, except between rapid transit and the Washington Street section of the Silver Line.
Paying directly with cash is only available on buses, Green Line surface stops, and the Ashmont-Mattapan Line; the higher CharlieTicket price is charged.

The MBTA operates "Inner Express" and "Outer Express" buses to suburbs outside the subway system.
Inner Express bus trips cost $3.65 with a CharlieCard or $4.75 without; Outer Express trips cost $5.25 with and $6.80 without.
Free transfers are available to the subway and local buses with a CharlieCard, and to local buses with a CharlieTicket.

CharlieTickets are available from ticket vending machines in MBTA rapid transit stations.
 CharlieCards are not dispensed by the machines, but are available free of charge on request at most MBTA Customer Service booths in stations, or at the CharlieCard Store at Downtown Crossing station.
 As given out, the CharlieCards are "empty", and must have value added at an MBTA ticket machine before they can be used.

The fare system, including on-board and in-station fare vending machines, was purchased from German-based Scheidt and Bachmann, which developed the technology.
The CharlieCards were developed by Gemalto and later by Giesecke & Devrient.
In 2006 electronic fares replaced metal tokens, which had been used on and off on transit systems in Boston for over a century.

Until 2007, not all subway fares were identical – passengers were not charged for boarding outbound Green Line trains at surface stops, while double fares were charged for the outer ends of the Green Line D branch and the Red Line Braintree Branch.
As part of a general fare hike effective January 1, 2007, the MBTA eliminated these inconsistent fares.
As of 1 July 2019, all subway trips (Green Line, Blue Line, Orange Line, Red Line, Ashmont-Mattapan Line, and the Waterfront section of the Silver Line) cost $2.40 for CharlieCard holders and $2.90 for CharlieTicket or cash payers. Local bus and trackless trolley fares (including the Washington Street section of the Silver Line) are $1.70 for CharlieCard holders and $2.00 for others. All transfers between subway lines are free with all fare media. Passengers using CharlieCards can transfer free from a subway to a bus, and from a bus to a subway for the difference in price ("step-up fare"). CharlieTicket holders can transfer free between buses, but not between subway and bus, except between rapid transit and the Washington Street section of the Silver Line. Paying directly with cash is only available on buses, Green Line surface stops, and the Ashmont-Mattapan Line; the higher CharlieTicket price is charged.
The MBTA operates "Inner Express" and "Outer Express" buses to suburbs outside the subway system. Inner Express bus trips cost $3.65 with a CharlieCard or $4.75 without; Outer Express trips cost $5.25 with and $6.80 without. Free transfers are available to the subway and local buses with a CharlieCard, and to local buses with a CharlieTicket.
CharlieTickets are available from ticket vending machines in MBTA rapid transit stations.  CharlieCards are not dispensed by the machines, but are available free of charge on request at most MBTA Customer Service booths in stations, or at the CharlieCard Store at Downtown Crossing station.  As given out, the CharlieCards are "empty", and must have value added at an MBTA ticket machine before they can be used.
The fare system, including on-board and in-station fare vending machines, was purchased from German-based Scheidt and Bachmann, which developed the technology. The CharlieCards were developed by Gemalto and later by Giesecke & Devrient. In 2006 electronic fares replaced metal tokens, which had been used on and off on transit systems in Boston for over a century.
Until 2007, not all subway fares were identical – passengers were not charged for boarding outbound Green Line trains at surface stops, while double fares were charged for the outer ends of the Green Line D branch and the Red Line Braintree Branch. As part of a general fare hike effective January 1, 2007, the MBTA eliminated these inconsistent fares.
Massachusetts Bay Transportation Authority