The RDR will cost employees joining pension schemes around £350 each, Creative Benefit Solutions warns.
The employee benefits consultancy says the RDR proposals would see employees paying advisory and management costs to join a company pension scheme up front.
These costs can currently be covered by commission which is payable over time and therefore manageable.
Creative Benefit Solutions chairman Doug Johnstone says: "These costs will impact on the number of employees saving for their pension. £350 is a significant sum of money and we fear people will opt out of occupational pensions, even with the forthcoming auto-enrolment legislation."
Johnstone adds: "Employees will have to pay £350 each time they join an occupational scheme, with people holding a number of jobs in their lifetime so the expense will build up."
He warns the proposed RDR changes could impact on a person's desire to move employers, or to be enrolled in a company pension scheme at all.
"We are supportive of the FSA in its efforts to protect consumers and ensure the financial services industry works for them," he says.
"However, we strongly believe that this is not the way to do it and we urge the FSA to open a dialogue with us and other pension scheme providers so that this injustice can be resolved."
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