At Retirement Choices (ARC), the investment platform soft launched two years ago by provider Aegon, has gained more than £1bn assets under management.
The GBST-powered platform, which aims to help consumers get more from their retirement savings, began a phased roll-out in November 2011 before a full launch last year.
It reached £1bn assets this month.
Adrian Grace, Aegon UK CEO, said: "While I'm delighted we have hit the £1bn mark, it's the pace we have built, delivered and grown this proposition that pleases me more.
"This has gone from a concept to a market-leading platform in the space of three years, which is quite simply unprecedented!"
Aegon said that, next year, it will focus on upgrading its existing customers onto ARC.
Grace (pictured) said: "This is only the start of our journey, we have extensive plans to build our proposition for customers, employers and advisers. We want all our customers to benefit from the innovation of ARC and this will be one of our key objectives next year."
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