Some employers are fretful about discussing automatic enrolment with their employees for fear of straying into "heavily regulated" financial advice, a study suggests.
A quarter of employers are worried about communicating the right messages to their workers, while a fifth fear incorrectly stating the benefits of their pension scheme, according to the report.
The findings form part of Aviva's second Working Lives study, which assesses employer and employee attitudes to workplace savings and benefits.
Aviva, which said it interviewed some 760 private sector employers and more than 4,000 employees for its study, said that, though more than 60% of companies had started providing information on auto-enrolment, only about a third of managers had opened a dialogue with staff.
"With financial advice being a heavily regulated and complex area, 25% worry about communicating the right messages to their employees," the report stated.
Overall, Britain's workers remain unsure on pension saving, Aviva said, with 37% of the employees it spoke to saying they will opt out of a scheme and 28% declaring themselves undecided.
Affordability is a key obstacle, with almost half (45%) of employees who do not currently take up the pension they are offered saying they do not have the cash to contribute to a scheme.
"Getting millions more people saving for retirement for the first time during difficult times is a real challenge - but automatic enrolment presents us with a once in a generation opportunity to get this right," said Mark Noble, Aviva's managing director of health and corporate benefits.
"Automatic enrolment will only become game-changing if employers, their advisers and the wider industry create sustained communications and engagement in the workplace to encourage employees to save."
The National Association of Pension Funds (NAPF) said opt-out rates remained a "big concern".
"The UK is miles off course when it comes to saving enough for its old age, and auto-enrolment could really help get us back on track," said NAPF chief executive Joanne Segars.
"If these vital reforms are to take root then people need to try to stick with their new pension. Saving for retirement is a necessity, not a luxury."
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