Union is a co-living development of two towers in the St John's area of Manchester, England. The first phase, a 112-metre (367 ft), 36-storey high-rise, is the first rent-by-the-room co-living building in the United Kingdom, where potential renters are matched with housemates based on their responses to a questionnaire. It was designed by Denton Corker Marshall and as of September 2025 is the 18th-tallest building in Greater Manchester. The second phase, consisting of a 32-storey building, is due for completion in 2025.