Some 30% of trust-based defined contribution schemes have breached retirement disclosure regulations, a report by The Pensions Regulator revealed.
And 6% of schemes will be referred to regulator casework teams to follow up the substantial changes required to their retirement literature or processes.
The regulator's investigation assessed the pre-retirement literature of 97 trust-based DC schemes in adherence with legislative requirements, good practice in areas such as the description and prominence of the open market option and the use of clear, plain English.
The report also showed 57% of schemes had scope for improving the standards of the retirement information they send to members.
TPR executive director of operations June Mulroy said: "Compliance with the legislative requirements is important as a minimum standard. But we expect to see adoption of good practice as the norm.
"This will help members to make the right decisions at retirement, which we recognise can make a significant difference to the income they receive."
The regulator also found just over one-fifth of retiring defined contribution members take up the OMO. It showed just 23% of DC retirees took up the OMO despite 98% of schemes offering it.
Mulroy added: "It is encouraging to see examples of excellent practice, but we do recognise that there is room for improvement. The economic downturn has had an impact on the value of many DC members' pension savings and as such the importance of making informed decisions is higher than ever."
TPR will send a letter to 4500 schemes highlighting the findings of the investigation and encouraging trustees to review the pre-retirement literature sent out to their members.CBI senior pensions policy adviser Jim Bligh said accused the regulator of spinning the results of the report.
He said: "Employers are committed to good practice in DC. Despite the spin given to these findings by the regulator, only 6% of firms were non-compliant with disclosure regs to a material degree, and even then the most common breach was in terms of timing, where the relevant disclosures were made, but late."
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