People with multiple jobs, who don’t reach the threshold for auto-enrolment, are missing out on as much as £90m a year as a group, Scottish Widows has found.
The firm called for the auto-enrolment threshold to be scrapped to help more people save for later life.
Currently any job earning less than £10,000 annually is not automatically enrolled.
And although workers earning between £6,032 and £10,000 can opt in if they want to, many are not doing so.
Scottish Widows estimates about 13 per cent of the UK’s 32 million workforce have more than one job and more than half of these are employer-based.
Of this group (about 2.5 million people) 59 per cent told the firm either all of their jobs or at least one paid less than £10,000 per year.
Based on the average salary from these jobs, collectively more than £90m of employer contributions a year could be claimed if the auto-enrolment threshold was scrapped, it said.
Robert Cochran, retirement expert at Scottish Widows, said: “Auto-enrolment was designed as a safety net for a country facing a pensions crisis.
“This year’s study shows some of the hardest working and most financially vulnerable members of society are slipping through the auto-enrolment net because of minimum earnings thresholds.
“This unfairly impacts multi-jobbers, who could be working the equivalent of full-time hours, yet without the financial benefit of having a single employer.”
The government has pledged to help people in this situation, as well as younger people, by mid-2020 but Mr Cochran said this was not soon enough.
In its annual retirement report, out today (6 June) Scottish Widows found the number of under 30s saving enough for retirement has risen 9 percentage points due to the success of auto-enrolment, which meant two in five workers aged 22-29 are now saving adequately for retirement, but more than one in five are still saving nothing for later life.
Saving levels across the rest of the working population have stagnated meanwhile at 55 per cent, down slightly from the 56 per cent prevalent in the years before.
Scottish Widows wants to see auto-escalation continued beyond 8 per cent, to a minimum of 12 per cent.
Mr Cochran said: “The fact that savings levels have stagnated for the last few years shows that auto-enrolment is not a silver bullet.
“It will be interesting to see if the step up in minimum contributions helps reverse this trend, but it doesn’t take away from the fact that the current threshold puts an unfair barrier in the way of low-paid workers and their ability to prepare adequately for retirement.
“We want to see it scrapped entirely at a much quicker rate than the government has suggested, to let all workers benefit from employer contributions.”
Alan Chan, director at IFS Wealth & Pensions, said: "I totally agree that the minimum age and earnings trigger for auto enrolment should be reduced as soon as possible so that more people can be part of their workplace pension."