Starting from 1920, Brunei was served by visiting priests from Jesselton (Sabah) of the Bishop from Kuching. A cemetry was consecrated in 1920. Brunei was visited in 1925 by Collis, and in 1928 by Chong En Siong. In 1929, Chong En Siong also visited Kuala Belait and Seria. An English medium school was opened at Kuala Belait in 1931 by En Siong. In 1931, Brunei was also visited from Labuan by lay reader Ng Thau Syn who was recruited from China.
In Brunei, English services were held at the Resident’s house while Chinese services were held at the shop house of businessman Leong Ng @ Yun Shak. The room at the shop house was later blessed by Danson, and called the ‘Hall of St. Andrew’. In 1933, Brunei came under the charge of Chin Phu Hin from Labuan. The new church in Brunei was consecrated on 10 October, 1934. Due to the depression of the 1930s, the congregation in Brunei swelled to 150 members. Chin Phu Hin moved to Brunei in 1937. In 1936, a concrete chapel at Kuala Belait was consecrated. Kuala Belait was also ministered to by Lim Siong Teck from Miri.
When the Japanese invaded Brunei in December 1941, Phu Yin took his family to Limbang for refuge. The churches at Brunei and Kuala Belait were destroyed during the War. Phu Yin moved back to Brunei after the War, and looked after Seria and Kuala Belait as well. Services in Brunei were held at ‘Tai Guan’, the residence of Ong Kim Kee’s family. The new church in Kuala Belait was consecrated in 1949, while the new one in Brunei was consecrated in 1950. John Leong (later Bishop of Kuching) was appointed a lay reader at Kuala Belait in 1950. The Church in Seria was consecrated in 1954, and dedicated to St. Margaret and All Hallows.
In 1955, Chong En Siong was transferred from Kuching to Brunei. In 1957, he opened a mission school (St. Andrew) in Brunei, initially using the church as a classroom. He was assisted in the teaching by his three daughters, Margaret, Kathleen and Grace. En Siong was succeeded by Vyvyan in 1963, who was in turn succeeded temporarily by Michael Lim in 1964. A.J. Blade came in 1965 and took over from Michael Lim. Blade was succeeded by Fowler in 1969. Fowler left in 1971 and Phillip Than became the priest in charge. Mathew Ubun succeeded Phillip Than in 1979, and stayed till 1984, when the latter went to England for further studies. John Yapp succeeded Matthew Ubun in 1984. Paul Van, the present vicar, succeeded John Yapp.
In 1955, Seria and Kuala Belait became a separate parish with the arrival of the first resident priest, Leonard Melling. The permanent church of St. Philip and St. James, Kuala Belait was consecrated in 1957. In the late 1950s, visits began to be made to Rempayoh, where a temporary chapel was built. Melling left in 1959 and was succeeded by Briggs. Seria had the following vicars in succession: Vicars (1960-64), Adams (1966-70), Tennant (1971-72), Tudball (1974-75), Blade (1977-78), Philip Than (1981-90/92-93), Noel Chin (1993-94) and Patrick Wong (1995-96). The present incumbent, Kenny Tan, took over in 1996. Kuala Belait became a separate parish in January 1980.