Hargreaves Lansdown saw assets under administration increase by 14% during the third quarter, traditionally a quiet period for the firm, driven largely by positive markets.
In an interim management statement, Hargreaves says assets grew to £19.9bn as at the end of September.
Ian Gorman, chief executive, says: "The rise in stock markets during the first quarter (FTSE All Share index increased by 12.7% from 2,543.47 to 2,867.58) has helped increase the value of assets under our administration. It is interesting to reflect on the investment climate a year ago.
"Investment euphoria was in abundance as the FTSE All Share index rose 21% between the start of July and end of September. In comparison the last three months have been dogged with fears of a double dip. The media is full of doom and gloom, cuts, and public sector union threats.
"Despite this it is encouraging that our business inflows during the first quarter have been resilient."
On the Vantage platform, which also grew 13% in size, net new business amounted to £550m while positive market impact played a bigger part increasing the assets by £1.71bn.
The statement says the first quarter of the financial year historically tends to be quietest for Hargreaves and this year has been no different. Net new business is consistent with the corresponding quarter last year when net new business inflows were £560m.
Also, Hargreaves gained 7,000 new clients on the Vantage platform during the quarter and the firm's Portfolio Management Service and range of multimanager funds saw assets swell by 11% to £2bn.
Operating revenue was 25% higher the corresponding quarter last year.
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