The analysis reveals that 84 businesses, representing more than two million employees, had complied with their auto-enrolment duties by the end of March 2013.
A spokesman for the Pensions Regulator said that there could be more workers in schemes as companies still have four months to register from their staging date, but declined to comment as to whether firms were not complying.
Charles Counsell, Executive Director of automatic enrolment for the Pensions Regulator, said:
“As a direct result of automatic enrolment, hundreds of thousands more people across the UK are now saving into a workplace pension, joining the 1.2 million of their colleagues who were already in a qualifying scheme. Some of these will have been contractually enrolled by consent into a qualifying scheme prior to their employers’ staging dates.
“The regulator continues its work to provide the vast numbers of employers still to stage with the information they and their advisers need so they can comply with the legislation and help millions more workers save for retirement in the coming years.”