St. Mary Parish in Pinckney, Michigan

North: Intersection of Iosco Township western boundary and Coon Lake Road in Iosco Township; Coon Lake Road east to Chilson Road.

East: Chilson Road south to Swartout Road; Swartout Road west to Pettysville Road; Pettysville Road southwest to Whitewood Road; Whitewood Road south to Shehan Road; Shehan Road west to McGregor Road; McGregor Road to the Livingston County Line.

South: The Livingston County Line (southern boundary) west to the Unadilla Township western boundary.

West: The Unadilla Township western boundary north becoming the Iosco Township western boundary; the Iosco Township western boundary north to Coon Lake Road to the point of beginning.

All Latin Rite Catholics living within the above described territory are considered members of St. Mary Parish, and as such, are subject to the spiritual jurisdiction of the Reverend Pastor of that Parish.