63. TET

Revenue: £65.7m (+9%)

Staff: 49

This London-based VAR's website bears glowing testimonials from a range of customers including Expedia, Pitney Bowes and Grangewood. A lack of fresh accounts means we have had to recycle its calendar 2020 revenue tally in the headline of this profile. Specialising in cybersecurity, hybrid infrastructure and digital transformation, TET (or ‘Trans European Technology' to use its full name) counts Cisco, NetApp, Microsoft, Palo Alto Networks, HPE, Virtual1, Dell and Lenovo as its eight strategic vendors.