The organ was built in 1883 by Thorold and Smith (later Jardines of Manchester) and was installed in the north chapel, replacing an earlier instrument that occupied a west end position. With two manuals and a pedal board, the organ is an excellent example of the craftsmanship of one of the most reputable organ builders of the period. The organ was moved to its present position during the 1964 reordering of the church.
Although built specifically for St Peter & St Paul, the original instrument was considered incomplete given the size of the building in which it is installed. It was therefore restored and enlarged in 1990 by the organ builders Bishop and Son of Ipswich so as to complete the instrument as it ought to have been built.