One of the earliest Anglo-Catholic congregations in Canada, it was established in 1874, moving twice before settling into its present building, adjacent to the Annex on the western edge of the University of Toronto's downtown campus.

Many people who do not live within the boundaries of the parish attend its services, especially students, staff, and faculty at the University of Toronto.

The aesthetic theorist and poet T. E. Hulme attended St Thomas's while living in Toronto briefly in 1906 after leaving Cambridge University.

Liturgy at St. Thomas's is more formal and complex than would be encountered in all but a few Anglican churches in Canada and indeed in the rest of North America today.

Of interest is its dedicated Acolytes' Guild and the parish's preservation of complex liturgical roles and minor orders like that of the subdiaconate, which are no longer found in the vast majority of Anglicanism and Western Christianity as a whole, including in contemporary Roman Catholicism.

Roy Hoult explains, sought to rediscover the forms of dress and general tenor of worship that pertained in England prior to their destruction at the time of the Reformation.

St. Thomas's is an example of this second kind of Anglo-Catholicism; its lack of lace and the predominance instead of plain albs and long surplices bear witness to this, as does the traditional Anglican arrangement of the chancel with its choir stalls.

St. Thomas's celebrates daily Low Mass and Morning & Evening Prayer, one of the only Anglican parish churches in Toronto which offers such a schedule.

The famous English accompanist Gerald Moore, who grew up in Toronto, was briefly an assistant organist at St. Thomas's.

Many St. Thomas's parishioners are active as performers, writers, and artists, and the church has participated in events like Nuit Blanche and Doors Open Toronto.

The parish, although well-known for its liturgical conservatism, houses a sizable portion of parishioners who embrace a more liberal Anglo-Catholicism, following trends in the Anglican Church of Canada, although theologically traditional elements remain alive and well.

Nowadays, however, seminarians from both Trinity and Wycliffe serve regularly during the academic term, involved in the liturgy and many aspects of parish, such as the Friday Food Ministry.