St. Mary's & St. William's Parishes at 19659 County Rd. 19, Williamstown, ON K0C2J0 CA - Mass Times and Schedules
| MASS SCHEDULE | |
| Sunday: | 9:00 A.M. (St. William's) 10:30 A.M. (St. Mary's) |
| Wednesday: | 9:00 A.M. (St. Mary's) |
| Thursday: | 9:00 A.M. (St. Mary's) |
| Friday: | 9:00 A.M. (St. Mary's) |
| Saturday: | 5:00 P.M. (St. Mary's) |
| OFFICE Hours | |
| Thursday: | 9:30 A.M. - 2:30 P.M. (St. Mary's small hall) |