Designed by Philip Wyatt, it has been described as being of "intrinsic architectural interest", having an "unusual scheme of development" and "occupying a significant position on the axis of Weymouth's Town Bridge".

[1] Holy Trinity was built at a time when new church accommodation was required to meet the needs of the growing population of Weymouth.

[2] A chapel of ease dedicated to St. Nicholas was also built in Weymouth during the 12th century, but suffered severe damage in the English Civil War.

Charles Sumner, on 6 August 1836,[5] The church's completion saw Holy Trinity become its own parish, separated from Wyke Regis.

[6] As the parish's population continued to grow over the course of the 19th century, Holy Trinity became too small and consideration was made whether to extend the church or build a new one.

The renovation work included the relaying of all flooring, reseating the church with new benches and reglazing the windows.