This year's ISA season was the strongest since 2002 with Q1 the best ever for net retail sales, according to IMA figures.
Assets under management in UK domiciled funds broke the £500bn barrier for the first time ever with a strong boost from ISA sales.
The 2009-2010 tax year was the best for ISA sales since 2001-2002, as investors put £3.5bn into the tax efficient wrappers. ISA money now accounts for around 20% of all authorised FUM.
Bonds supplanted equities as the best selling asset class in March as investors rotated into safe haven areas.
The month saw total net retail sales of £1.8bn, which is the highest level for this month since 2006 and the fourth highest March on record.
Fixed income funds took £930m of net new money but equities suffered net withdrawals of £218m, partially reversing inflows of £673m in February. This also reversed the trend of the past six months, when equities outsold bonds.
The Strategic Bond sector took top spot for the second month in a row, with net retail sales of £477m. This was ahead of Global Bonds on £295m followed by Property, Cautious Managed and Absolute Return. The lowest selling IMA sector during March was UK All Companies with net retail outflows of £689m.
Richard Saunders, IMA chief executive, says topping £500bn in onshore funds "would have been unthinkable a generation ago".
He adds: "The strong propensity to save, as seen in 2009, has continued this year."
Funds under management for UK domiciled funds passed £100bn in 1995, reaching £400bn in 2006.
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