Hargreaves Lansdown saw its assets under management increase to £94.1bn in the three months to the end of September.
The 3 per cent increase in assets was driven by net new business of £1.3bn, which Hargreaves Lansdown bosses attributed to investment in digital marketing and "ongoing wealth consolidation" onto its platform.
On top of this, the FTSE 100 company benefited from positive market movements of £1.2bn.
Chris Hill, chief executive of Hargreaves Lansdown, said: "The past quarter has seen an uncertain market environment and weak investor sentiment resulting in an industry-wide slowdown in net retail flows.
"Despite this backdrop, we believe the strength of our business model positions us well for when sentiment improves."
During the quarter Hargreaves Lansdown took on 29,000 new clients, taking its total number of active clients to 1.12m.
The Bristol-based company also saw its net revenue for the three months increase by 16 per cent on the previous quarter, reaching £120.8m.
Hargreaves Lansdown also highlighted the effect of its cash marketplace service, Active Savings, which allows its clients to find more attractive interest rates for their cash savings.
During the quarter the company added three more banks to this service which allowed it to increase the level of marketing and promotional activity in early September.
The company now has more than £100m managed through this service, which launched in early September.