Transact's assets under administration rose by 15.6 per cent in the six months to the end of March 2019.
According to its market update, released to the stock market this morning (17 May), Integrafin, the company which owns the Transact platform, reported net inflows of £1.81bn.
Integrafin reported an operating profit of £22.2m, an increase of £1m on the same six month period in 2018.
Profits were hit by one-off costs of £2.9m, most of which came from the cost of Integrafin listing on the stock market last year.
Ian Taylor, Integrafin's chief executive, said: "We are pleased to announce a solid set of results for the first half of the year. Despite the backdrop of political uncertainty and stock market volatility, Transact has maintained strong positive H1 net inflows.
"We remain confident we are well placed to sustain growth as we move into the second half of the year."
Transact now has 173,000 clients.
The company announced a dividend of 2.6p per share for the six month period, having not paid any dividend for the same six month period in 2018.
Integrafin’s share price has risen from £3.41 to £4.03p over the past year.