24. OneCom

Revenue: £168.6m (+83%)

Staff: 606

This Hampshire-based business comms provider last month made its ninth acquisition since 2019 in the shape of Midlands peer IMS Technology Services. The LDC-backed outfit's revenues swelled by 83 per cent to reach £168.6m in calendar 2021 as previous acquisitions - including those of Olive and 9 Group - turbo-charged its top line. Around half of OneCom's top line is now generated from outside its traditional mobile stomping ground, the Vodafone, Microsoft, Google, Mitel, Samsung, Apple, Gamma and Five9 partner revealed.