Auto-enrolment queries are beginning to mount for The Pensions Advisory Service (TPAS) and now account for up to 3% of monthly calls.
The organisation's annual review said employees and employers alike had already started to contact TPAS to find out more about their rights and responsibilities from 2012.
TPAS chief executive Marta Phillips, pictured, said: "We are starting to see some concern about automatic enrolment indicating that we all have work to do to help people affected understand the issues."
However, the report revealed the volume of complaints referred to TPAS dropped by 22% last year, driven by a reduction in problems over delays and favourable markets.
Phillips explained: "We received fewer complaint cases which reflects well on schemes and administrators, but some of this may be due to the improvement in investment conditions."
It found a fifth of complaints now related to mistakes while the number of enquiries around voluntary National Insurance contributions also fell.
On occupational pensions, the service reported continued growth in the number of deferred members needing help tracing pension schemes and questions about ill-health early retirement decisions, accounting for 3% and 4% of complaints across the board.
The number of people contacting the helpline for clarification of their benefits and how tax affects pensions and tax free allowances had risen by 47% and 48% respectively over two years, TPAS said.
TPAS said visits to its website had hit two million and visitor numbers were up by two thirds over the year. It handled more than 63,000 calls and 18,000 written enquiries.
An independent survey conducted on behalf of the Department for Work and Pensions found 94% of helpline users were either "satisfied" or "very satisfied" with the service received.
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