More than half the UK's part-time workers are in jobs that they feel fail to capitalise on their qualifications, skills and previous management experience.
Working part-time can 'scar' income, earnings potential and promotion prospects for life while the economy loses essential skills, a new report by the Equal Opportunities Commission claims.
A quarter of the UK workforce, some 7.4 million people, are part-time workers, the overwhelming majority of whom (78 per cent) are women.
A survey of 2,300 part-time workers carried out as part of the report suggests that half (51 per cent) of those employed part-time are currently working below their potential in that they feel that in previous jobs they did more staff management or supervision, used higher qualifications, or used a higher level of skills.
The report, "Part-time is no crime Ė so why the penalty?", argues that a key trigger for working part-time is the need to balance work and caring responsibilities.
But because of the lack of flexibility in their chose careers many women have to take up alternative work which is often low paid and part-time.
Part-time work has a 'scarring' effect on earnings. The longer a person is in part-time work, the lower their wages are likely to be, even if they return to full-time work.
Women who have spent just one year in part-time work can still expect to earn 10 per cent less after 15 years than those who worked full-time for all 15 years.
In addition, part-time workers are 40 per cent less likely to receive in-work training than their full-time counterparts and if they are women, they will also earn an average 40 per cent less per hour than male full-time workers.
Meanwhile, the odds of a woman being in part-time work increase by almost eight times if she has a second child aged 0-4 Ė and the EOC claims that the lack of availability of affordable, good quality childcare is a key trigger for entry into part-time work.
The report argues that the way to tackle the stigma and disadvantage faced by those who work part-time is by opening up flexible working practices at all levels of the economy and by opening the right to request flexible working to parents of older children and carers.
Research last year by the charity Working Families found that six out of ten flexible working requests are agreed by employers.
However it also revealed that flexible working was not an option in many managerial roles and that women in management positions are told that they can only work flexible hours if they accept a demotion
Julie Mellor, Chair of the Equal Opportunities Commission, said that Britain would find itself in a crisis if it does not address the need for flexible hours at work.
"Women are hardest hit by the part-time 'penalty' which channels them into low-paid jobs with poor prospects often because they take on more of the caring role at home," she said.
"Many people choose to work part-time but they don't choose low pay.
"What we need is to enable parents of older children and carers to ask their employer to work flexibly, and encourage employers to offer better paid jobs on a more flexible basis. Only that way can we keep essential skills in the economy whilst allowing people to do the vital role of caring for others."