The Resolution Foundation found workers aged 65 and over are most likely to have no paid holiday entitlement, despite all employees being legally entitled to at least 28 days a year of annual leave, pro-rated for part-time workers.

The think tank also found that workers aged 25 and under are almost twice as likely be underpaid the minimum wage as any other age group.

The analysis revealed workers in small firms (with fewer than 25 employees) are most likely to miss out on pay slips and holiday leave, as are workers on zero-hours and temporary contracts.

The Resolution Foundation welcomed steps by the government to increase the resources and powers of bodies such as HMRC and the GLAA (Gangmasters and Labour Abuse Agency) in recent years.

However, it said the UK still largely relies on individuals to hold non-compliant firms to account, with the Employment Tribunal (ET) system receiving over 100,000 applications last year.

Lindsay Judge, senior economic analyst at the Resolution Foundation, said: “The UK has a multitude of rules to govern its labour market – from maximum hours to minimum pay. But these rules can only become a reality if they are properly enforced.

“Labour market violations remain far too common, with millions of workers missing out on basic entitlements to a pay slip, holiday entitlement and the minimum wage.

“Our analysis suggests that while violations take place across the labour market, the government should also prioritise investigations into sectors like hotels and restaurants, along with firms who make large use of atypical employment contracts, as that’s where abuse is most prevalent.”

The think tank said the scale of labour market abuse highlights the need for the state to step up to ensure the UK’s labour market rules are better enforced.

It welcomed the government’s plans to create a new single enforcement body to tackle labour market abuse, though it said that the new body must be properly resourced in terms of funding and staff, and have legal teeth.