This growth was 10.1% organic, while 5.1% was down to acquisitions.
JTC also reported an increase in earnings to £17.9m – an rise of 11.2% on the previous year.
Institutional Client Services saw a 19.6% in gross revenue, while Private Client Services rose by 10%.
CEO Nigel Le Quesne commented: “In the first half of 2020 we all faced extreme challenges at very short notice. At JTC our priorities were the safety of our people, uninterrupted service for our clients and maintaining the long-term performance of the Group. The strong results delivered in H1 are testament to the highly resilient nature of our business, the outstanding quality of our people and the loyalty of our client base.”