Cofunds has reported a 10% dip in profits for last year, citing investment in retail distribution review (RDR) readiness as the reason for the drop.
Profit before tax fell from £7.9m in 2010 to £7.1m in 2011 in what chief executive Martin Davis labelled a "tough" year.
Cofunds said RDR preparation - both in terms of getting its systems up to date and helping advisers prepare for a post-2013 world - accounted for the slide in profits.
Expenses increased from £56.1m in 2010 to £65.5m in 2011, it said.
Elsewhere, the platform saw an increase in turnover from £61.3m in 2010 to £70m last year, whilst assets under administration grew from £30.3m to £35.8m.
Gross sales increased 43% from £8.5bn to £12.2bn whilst net sales surged 54% from £4.8bn to £7.4bn.
"Last year was a tough year but we still achieved very strong sales and continue to outperform markets with our assets growing to nearly £36bn," said Davis (pictured).
"Despite a significant increase in investment in systems and getting our advisers ready for RDR, we still delivered good profits."
The platform said it would continue to invest in the business this year, adding RDR preparation will take precedence over the wider rollout of exchange traded funds (ETFs) and investment trusts, which it said remains a "work in progress".
ETFs and investments trusts are currently available to Cofunds' investors via a pilot project with Barclays Stockbrokers.
Meanwhile, Davis said "unanswered questions" remained concerning platform rebates and legacy assets but added the platform has enough "flexibility" to react to any scenario.
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