One in three people not retired or unemployed and questioned by polling firm Survation for the GMB was defined as being in a zero or short-hours contract, temporary work, the gig economy, underemployed or at risk of false self-employment.

With more than 31m people in the UK workforce, the GMB estimated that more than 10m are in ‘precarious employment’.

The poll also found that, of the 1,000 ‘precarious workers’ surveyed, 61% had suffered stress or anxiety as a result of their current job.

The same proportion had been to work while unwell for fear of not being paid, losing their job or missing out on future hours. More than a third said they would struggle to cope with an unexpected bill for £500.

GMB general secretary Tim Roache said: “This paints a shocking picture of the modern world of work.

“Up to 10m people go to work either not knowing what their hours are, if they’ll be able to pay the bills or what their long-term prospects are.

“We hear a lot about employment figures. Well this research shows the today’s job market is based on a shaky foundation of insecure work where people are doing their best but still not able to get on. Insecure work impacts on people’s health, their families and whether they are able to plan for the future.”

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