Hargreaves Lansdown recorded a 12.8% rise in assets under administration over Q1, as its Vantage platform posted £1bn of net new business.
Assets on Vantage increased by 13.2% to £16.3bn over the three months to 31 March, taking the group's total AUA to £17.6bn.
Vantage saw £1bn of net new business inflows and was also benefited by a £900m rise due to positive market movements and other growth factors.
The value of assets held in the Hargreaves' Portfolio Management Service and range of multi-manager funds increased by 11.8% over the quarter.
Hargreaves also posted strong new ISA contributions for the full tax year ended 5 April, taking in £812m compared to £412m the previous year. Investments into SIPPs - including transferred business and basic rate tax relief - was £1.35bn for this the tax year, up 24%.
Active clients on Vantage increased by 18,000 over the first three months of the year, to 318,000.
Group chief executive Peter Hargreaves says third quarter of its accounting year has historically been the most buoyant for the company.
"This year there have been additional positive factors," he says.
"We informed clients of our belief that stock markets would rise in the first three months of 2010; a brave call which proved accurate, as during the group's third quarter, the FTSE All Share increased by 5.4%.
"Clients deduced that interest rates were likely to remain low. We believe that this, together with the fear of higher taxes, has galvanised investors into seeking tax efficient investments.
"The Government have on the one hand, assisted our business with the increase in the ISA allowance, whilst at the same time provided pension legislation so complicated and incomprehensible that it left investors bemused. Nevertheless we experienced our best quarter ever."
Succeeding co-founder Simon Rogerson
Janus Henderson Global Dividend Index
More than 10 million shares allocated
Long-term strategic holding
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