I was just wondering about this the other day. Do they except these or do they use something else?
You can use your smartrip card on MTA except Commuter buses
I think it works the other way around too, like you can use the Charm card in the WMATA system.
IIRC, Commuter buses don't have electronic fare boxes, just old-fashioned cash drop-in boxes, which is why Smartrip won't be accepted there. I think one reason for this is because many commuter routes use the non-MTA branded buses, which obviously won't be all fitted in with the same electronic farebox.
Okay cool, thanks!
If you want to try riding on a MTA commuter bus try the route 201 which runs hourly all day in both directions 365 days a year between Gaithersburg and BWI Thurgood Marshall airport. Fare is $5 cash each way or MTA commuter card. It stops at Shady Grove Metro. The route uses MCI D4500 rest room equipped coaches that display the best wrap in the area. It is a fast ride using the ICC, I-95 and other highways.