Governance failings in hybrid pension schemes are putting members' benefits at risk, The Pensions Regulator (TPR) has warned.
A poll of 150 schemes with a combination of defined benefit (DB) and defined contribution (DC) features suggested trustees did not always understand their scheme's structure and the benefits it offered.
This lack of understanding increased the risk of members receiving misleading communication or incorrect retirement benefits, the watchdog warned.
TPR's poll also said half of schemes mixed their DB and DC assets together in the same bank account or investment fund, and in some cases these were not identified separately.
From November the regulator said it will ask additional questions of DB and hybrid schemes in their annual returns to better monitor the arrangements.
June Mulroy, executive director for DC, governance and administration at TPR told delegates at last week's National Association of Pension Funds (NAPF) annual conference she wanted to "get under the skin" of hybrid schemes.
She said today: "Our research indicates some schemes are so complex that even those accountable for running them struggle to understand their workings.
"I am concerned some hybrids have overly complex scheme rules and out-of-date structures based on legacy advice."
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