The number of workers on zero-hours contracts could be one million – four times as high as official estimates, according to new research.
The Chartered Institute of Personnel and Development (CIPD) said its survey of 1,000 employers showed that one in five employed at least one person on a zero-hours contract, under which staff are not guaranteed work from one week to the next.
Firms in the voluntary and public sectors as well as the hotel, leisure and catering industries were more likely to use zero-hours contracts.
Separate research among almost 150 zero-hours contract workers revealed that 14 per cent said their employer failed to give them enough hours to have a basic standard of living.
The workers polled averaged just under 20 hours a week and were most likely to be aged between 18 and 24 or over 55.
The Office for National Statistics (ONS) said last week that 250,000 people in the UK were on zero-hours contracts at the end of last year.
The CIPD, however, said the figure could be closer to one million. Chief executive Peter Cheese said: “Zero-hours contracts are a hot topic and our research suggests they are being used more commonly than the ONS figures would imply.
“However, the assumption that all zero-hours contracts are bad and the suggestion from some quarters that they should be banned should be questioned.
“Zero-hours contracts, used appropriately, can provide flexibility for employers and employees and can play a positive role in creating more flexible working opportunities.
“This can, for example, allow parents of young children, carers, students and others to fit work around their home lives. However, for some this may be a significant disadvantage where they need more certainty in their working hours and earnings, and we need to ensure that proper support for employees and their rights are not being compromised through such arrangements.
“Zero-hours contracts cannot be used simply to avoid an employer’s responsibilities to its employees.”
Business Secretary Vince Cable has ordered a review of the controversial employment contracts.
Dave Prentis, general secretary of the Unison union, said: “The vast majority of workers are only on these contracts because they have no choice. They may give flexibility to a few, but the balance of power favours the employers and makes it hard for workers to complain.
“Not knowing from week to week what money you have coming in to buy food and pay your bills is extremely nerve-wracking. Having your working hours varied at short notice is also stressful and it makes planning, childcare arrangements and budgeting hard.
“Unison would like to see the use of these contracts banned”