Union Chapel is a working Congregational church, live-entertainment venue and charity drop-in centre for the homeless in Islington, London, England.

[citation needed] The Margins Project, based in the Union Chapel, provides a range of support services to people facing homelessness, crisis and isolation.

It operates a twice-weekly drop-in that provides advice around accessing benefits, support showers and laundry facilities.

Between 1805 and 1809 a new chapel was built by Henry Leroux[5]: 170  on the present site in Compton Terrace, just off Upper Street, and the congregation moved to it in 1806.

It was replaced by the current building in the Victorian gothic style of architecture, designed by James Cubitt of Loughton and built between 1874 and 1877, with further additions from 1877 to 1890.

[12] The charity Union Chapel Project established in 1991 organises activities including gigs and events to help raise money for the building and open it up.

[citation needed] It is one of just two organs left in the United Kingdom, and the only one in England, with a fully working original hydraulic (water powered) blowing system, which can be used as an alternative to the electric blowers.

Commissions have included work from Éliane Radigue,[19] Low, Hildur Guðnadóttir, Adam Wiltzie, Phil Niblock,[20] Darkstar, Philip Jeck, Sarah Davachi,[21] and Mark Fell.