First Baptist Church Waterloo is the result of a pioneer home mission’s project by Benton Street Baptist Church, Kitchener in June 1931. By January 1934 the Mission had outgrown its facilities and it was decided to purchase property at the corner of John and Caroline Streets in Waterloo. The purchase was completed in March 1934 and this site was to be the home of First Baptist Church until 1982. The Church began a radio ministry in February 1938 over radio station CKCR. A radio ministry still continues today with the weekly Sunday Morning Worship Service broadcast live over radio station CKWR with live streaming over the internet.
In 1940 the Church commissioned and sent one of its own young ladies to the foreign mission field, under the Sudan Interior Mission, to serve the Lord in Nigeria. Since then the Church has continued to have a strong missions outreach, supporting missionaries at home and on foreign soil. This was the beginning of what was to become a key ministry of the church. Today the church actively supports missionaries and missionary families and numerous mission projects in Canada and overseas. Members of the congregation have participated in short-term foreign missions trips to Jamaica, Haiti, Dominican Republic, Venezuela, Korea, The Philippines, Ukraine and Burkina Faso in West Africa, where the congregation has generously contributed towards projects for a children's school at the Village of Hope and to a water project in the village of Lipa.
Church planting has been part of the ministry of the church and in 1969 and 1989 three new churches were planted. In May 1969 Faith Baptist New Hamburg held its first Evening Service and in October 1969 Grandview Baptist Church in south-east Kitchener, held its first Sunday School and Morning Worship Service. In September 1989 Community Fellowship Baptist Church (now Creekside Church) held its first Morning Worship Service.
In March 1982 the church held its first Sunday Morning Worship Service in the new sanctuary of its present facilities. December 1982 saw the first residents moving into the Woodland Terrace seniors residence, which is an integral part of the ministry of First Baptist.