In 1776 a Methodist tallow chandler, Thomas Mann from Rudgwick, moved to Horsham and began preaching. A building on Horsham Common, known as Hampers Barn, was licensed as a place of worship. The early society seem to have included some former Baptists. But there was no significant Methodist growth until the 1830s, when the first chapel, seating 180, was built in London Road in 1832 with substantial support from Miss Catherine (Kate) Ireland, who had been converted to Methodism in 1827.
The Religious Census of 1851 recorded congregations of no more than 30 in the morning and 40 in the afternoon, due to 'the Puseyite influence and [the] tyranny of the High Church party'. But the 1860s saw a period of growing prosperity, partly with the growth of the town itself and partly through the arrival of prosperous tradesmen, such as the Cramps and the Charts, and their families. London Road chapel was replaced by a larger church in 1883 and there was a flourishing Sunday School, for which more adequate premises were provided in 1897. The church continued to develop its ministry throughout the 20th century. One of its members, Sir Michael Checkland, was Vice-President of the Conference in 1997.
In 1877 the Rev. Joseph Dinnick, one of five brothers in the PM ministry, was sent by the General Missionary Committee to establish a Horsham Mission. A society was established at a group of cottages known as Star Row and a chapel was opened on Good Friday, 1878, with a Sunday School hall added in 1896. The chapel was renovated in 1927 to mark its Jubilee and three years later the property was at last cleared of debt. In 1936 the church was enlarged, with the addition of a vestry, an organ loft, pulpit and choir stalls. Further improvements were made in 1960 and1970; and following modernisation in 1971 what had been known as Roffey Methodist Church was renamed 'St. Andrews'. There were two other PM chapels in the town, at Rushams Road (1885; closed by 1911) and at East Street (1892; closed by 1933).