St Paul's, Onslow Square is a Grade II listed Anglican church in Onslow Square, South Kensington, London, England. The church was built in 1860, and the architect was James Edmeston. In the late 1970s, the parish of Holy Trinity Brompton merged with the neighbouring parish of St Paul's Onslow Square. St Paul's was declared redundant.
An attempt by the diocese to sell the building for private redevelopment was thwarted in the early 1980s when local residents joined with churchgoers to save the church. In the late 1980s, the Parochial Church Council requested that the redundancy be overturned which allowed curate Nicky Lee and his wife Sila to plant a congregation there as well as undertake some building structural maintenance work. At its peak in the 1990s, this congregation had grown to several hundred.
In 1997, the congregation at St Paul's divided into three, with some going with curate Stuart Lees to plant a church in Fulham; others returning to Holy Trinity with Nicky and Sila Lee; and others forming the St Paul's Anglican Fellowship and remaining based at St Paul's with John Peters. This last group left in 2002 to plant into St Mary's, Bryanston Square.
During 2007, after plans by HTB to rebuild the 1960s offices were withdrawn following difficulty in getting support from local residents, HTB decided to undertake some renovations and to resume services in the church. St Paul's launched 9 am and 6 pm services in September 2007 and followed with an 11AM service on January 20, 2008 and a 4 pm service on 28 September 2009. In December 2009 the upstairs balcony was recommissioned for worship, having previously been used for administrative offices (the office occupants having moved to HTB's nearby office building purchased in 2008).