Revenue: £558.3m (+11%)
Net profit margin: 2.1% Staff: 798
Double-digit growth in hardware, software and services sales fuelled a 17 per cent revenue hike at the UK arm of this global reseller in its year to 31 December 2018. Net profits swelled from £8.1m to £11.4m as gross profits grew at a faster rate than administrative expenses. Since year end, Insight Direct's NASDAQ-listed parent has acquired arch rival PCM in a blockbuster $580m deal. Having only opened shop in 2017, PCM's UK business turned over £35.6m last year, employing 120 staff, compared with Insight Direct's 800. Globally, Insight turned over $6.7bn last year.