The report analysed data from the Office for National Statistics to find that 136,000 more workers were given zero-hours contracts in April to June 2023 compared with the same period in the previous year. More than half (65%) of the new contracts were given to people aged 16 to 24.
One in 10 (13%) young workers in the UK were on zero-hours contracts in 2023.
The Work Foundation’s Insecure Work Index found that around three quarters (73.5%) of people aged 16 to 65 who are currently on zero-hours contracts in the UK are in severely insecure work, meaning that they face contractual and financial insecurity, and a lack of access to rights and protections.
Read more: Workers unaware of zero-hours contracts rights
Only 6.1% of the 1.1 million people are in secure employment, with a regular income and access to rights.
Gary Wedderburn, advisor at Acas, emphasised that people on zero-hours contracts are legally entitled to employment rights.
He said: “People employed on zero-hours contracts can be legally classed as a worker or an employee, and so are entitled to rights on the same basis as other workers and employees, depending on their employment status. For example, they are entitled to the national living wage, national minimum wage, holiday pay and rest breaks.
“Zero-hours workers also have other protections if they want to work for more than one employer. An employer must not to try to stop a zero-hours worker from working for another employer by putting an exclusivity clause in the contract, or treat them unfavourably for working for more than one employer.”
However, Kevin Poulter, employment partner at law firm Freeths, said zero-hours contracts can create financial uncertainty.
Speaking to HR magazine, he said: “Zero-hours contracts can sometimes be the best approach, allowing some flexibility around working time, obligations and the freedom to choose when and when not to work.
Read more: MPs back workers' right to request regular hours
“These findings suggest that young people in particular may not be given the opportunity to work under permanent and full-time employment contracts, which can result in unstable pay, limiting opportunities for financial independence and uncertainty of working arrangements and conditions.”
Wedderburn added that employers can lessen these problems by following best practice: “The employer should make it clear that the work is not guaranteed, the employee or worker doesn’t have to accept it, and that there is a fair and transparent way of sharing out the work.
“There should also be a clear policy on cancelling, organising and changing the work, including the notice employers will give and details of any compensation.”
The index revealed that black workers are 2.7 times more likely than white workers to be on zero-hours contracts and workers from multiple/mixed backgrounds are 2.3 times more likely than white workers to be on zero-hours contracts.
Meanwhile, women are 1.2 times more likely to be on zero-hours contracts than men.
Young workers (aged 16 to 24) are 5.9 times more likely to be on zero-hours contracts. Young workers who are not students are 3.5 times more likely than other age groups to be on zero-hours contracts.
Alice Martin, head of research for Lancaster University's Work Foundation, said: “Zero-hours contracts have previously been hailed the answer to flexible work. But our research shows that too often, it is only employers that have choices. Workers do not.
“The data shows these contracts affect certain workers more than others. Young workers – particularly young women – are bearing the brunt of policymakers' inaction.”
The Work Foundation’s report made recommendations on how zero-hours contracts should be regulated.
It called for employers to provide guaranteed contractual hours for all roles: either hours per week, hours per month or annualised hours. The foundation also recommended that anyone working 25% more than their contracted hours should to have a right to an amended contract, if they want it, that reflects their actual hours.
The index's authors also called for a three-week notice period for shifts, and for labour market enforcement resourcing to be increased.
Martin added: “A stable job and income have never been so important. But with insecure work now such an ingrained feature of the UK labour market, it is not something that can be solved overnight.
“Zero-hours contracts are just one of many issues that need resolving. Using our roadmap to reform their use will certainly take us closer to a more stable labour market and a happier, healthier workforce.”
