| 1954 | 1st Mass on November 21, at Grange Hall as mission church of St Patrick, Owego |
| 1955 | October 3 Certificate of Incorporation for St Margaret Mary Parish |
| 1956 | New Street church was dedicated. |
| 1959 | Fr Valentine Jankowiak appointed as first pastor of SMM Church |
| 1967 | Current church on Pennsylvania Avenue dedicated |
| 1968 | Parish Council formed |
| 1974 | Fr Elmer Schmidt appointed as second pastor |
| 1975 | Church hall completed |
| 1981 | Statute of the Risen Christ in front lawn dedicated |
| 1983 | Fr David Simon appointed as third pastor |
| 1984 | 1st annual Mission for evangelization and renewal |
| 1984 | 1st Pastoral Associate and 1st Pastoral Musician hired |
| 1985 | Stephen Ministry formed to reach out to others in time of need |
| 1991 | Sanctuary renovated |
| 1998 | Tioga Regional Pastoral Council formed to unite six parishes in Tioga County |
| 1999 | Fr Robert Ring appointed as fourth Pastor |
| 2001 | Fr David Bonin appointed as fifth Pastor |
| 2002 | Sr Marie Suzanne Hoffman, SSJ appointed Pastoral Administrator |
| 2003 | Blessed Trinity Parish formed and Rev William A Moorby appointed Pastor |
