While Transportation Secretary Stephanie Pollack sees a distinction between MBTA fares and the monthly passes purchased by regular users, she has no plans to raise pass costs more frequently than fares are allowed to increase.
A 2013 state law limits fare increases on the T to no more than once every two years. Pollack has identified a distinction between fares and the passes, which she describes as "discounts" because they allow for unlimited travel for a flat cost. For regular riders that works out to a smaller cost per-ride.