AJ Bell reported a 60 per cent drop in the number of defined benefit pension transfer customers moving onto its platform, and said it expected the decline to continue.
In a trading statement covering the three months to the end of March 2019, the company reported DB transfer inflows of £200m for the period, compared with £500m for the same period in 2018, a decline of 60 per cent.
In the statement, the company confirmed it expected the decline to continue as part of a wider "industry trend".
The platform added 10,000 new customers during the quarter, to bring the total to more than 200,000, with assets under administration on the platform rising by 9 per cent to £40.6bn.
Net inflows on the advised platform were £600m, down from £1bn in the same quarter last year, while inflows to the direct-to-consumer platform were flat at £400m.
Overall AJ Bell saw inflows of £1bn - down from £1.4bn last year - while market movements contributed £2.3bn.
Non platform assets grew by £200m due to market movements, with zero net inflows.
AJ Bell floated on the stock exchange in December 2018, and since then the share price has risen from £2.20 to £3.75.
Andy Bell, the co-founder and chief executive of AJ Bell, said: "Trading in the second quarter of our financial year remained robust despite continued weak investor sentiment.
"We continued to attract new customers and assets to our platform, with both measures hitting new highs during the period. This positions us well for an improvement in investor sentiment.
"We are due to announce our interim results on May 23 and we expect our financial performance to be slightly ahead of current market expectations."