There's a parking lot across the street as well as on street meters. I believe that MaMaison will validate your ticket. I'm not entirely certain for how long so you might give the restaurant a call. I hope that this helps, and you both have a wonderful day! 💗
Seating outside can be problematic. Our table was lopsided and near to a trashcan. Plus you are right across from Mass General so expect a lot of traffic. I would recommend inside dining.
It is on street meter parking or the Charles River Plaza garage. Ma Maison does validate for the Charles Street Garage (not plaza) is good for two hours and costs $14 I believe.
Thanks! Your answer is awaiting moderation.