Tens of thousands of Uber drivers in the UK could qualify for holiday and sick pay when an employment tribunal reconvenes in London on Wednesday, in what has been heralded as the employment law case of the year.

In July lawyers representing 19 drivers contested their status as self-employed workers. They argued that the drivers’ employment terms and conditions meant they were not technically self-employed and should therefore be entitled to a range of benefits such as pension contributions as well as holiday and sick pay.

The case is emblematic of the growth of the gig economy, where companies use self-employed contractors rather than employees.

Uber has about 30,000 drivers in the capital and has expanded to several other UK cities. It says it is not a transport company but a tech firm that provides an app that links drivers to customers. Lawyers for the drivers claim they are not self-employed because they are rated by customers and do not know drop-off destinations before the customer gets in the car. The case is being supported by the GMB union.

In a witness statement, one driver said in one month his net earnings were £5.03 an hour, and would have been £3.70 an hour if not for Uber’s “surge” pricing – higher charges imposed when demand is high.

Uber claimed that, based on the total number of hours logged into the app, the driver had been paid £13.77 on an average hourly basis. The judgment from the employment tribunal may be delivered on Wednesday or in the coming weeks.

The Guardian asked Uber drivers for details about their experiences working with the company. None of the UK drivers contacted said they earned more than the national living wage and some said they earned less when Uber’s deductions and running costs were taken into account.

Uber drivers have 20-25% of their income deducted as commission each week. That proportion can increase if any additional deductions are made, such as a refund after a passenger complaint.

One Uber driver, from Croydon, said he had used the company to pick up fares for more than a year and that working with the company had mostly been a good experience.

However, he said Uber could do more to ensure its drivers were paid a decent wage: “The positive side for me is the flexibility. But on the negative side, the fares are pitched too low. By the time you take out your expenses and the car you use to carry out the work, you’re looking at probably below the national living wage.”

He earns an hourly average of £12-£17 before costs and deductions, including the the 20% commission taken from his earnings by Uber. Another Uber driver, in Leeds, explained that he uses the ride-sharing app as a part-time job to supplement his income. He has 80-100 customers a week and says the security in being paid and knowing who he is picking up is why he uses the service.

However, he also says his earnings are often less than the national living wage. “To be honest, it’s the minimum wage, maybe £7 to £7.20 after you take all your expenses. Sometimes it’s even less than the minimum wage because it is quite expensive with the insurance and everything,” he said.

According to Uber, its UberX drivers earn well above the national living wage, with the average reported income at £16 per hour after the company deducts its commission.

Additional reporting by Rachel Obordo