Three thousand Amazon delivery drivers could get £140million in higher pay if a legal challenge over workers' rights succeeds.
Law firm Leigh Day says a minimum of 3,000 drivers could get more than £140million compensation in total.
Drivers could get £10,500 for each year they have delivered for the company, according to Leigh Day.
The firm wants to bring a class action, claiming that the drivers hired by Amazon from third-party delivery firms should have the same rights as its own drivers.
Leigh Day says third-party drivers are self-employed, so do not get minimum wage or holiday pay automatically.
The law firm says it has already started legal action working for two Amazon third-party drivers, but wants others to join a group action.
Group actions are where several claimants with a similar case band together to bring one single lawsuit against a company.
Leigh Day said that third-party drivers should get more rights because Amazon treats them almost like its own staff.
For example, they have to meet a delivery schedule set by Amazon, Leigh Day claims.
Drivers also said they are not able to bring parcels back to the depot so must use extra fuel to redeliver at the end of the day. This, combined with charges for van rental, fuel, and insurance can leave them with very little earnings.
Amazon driver Bill Lightfoot (not his real name) said: “The work is horrendous because Amazon control everything you do. There were times I was out on delivery, and I’d stop for a few minutes, and they’d ring up and ask why I was parked up.
"The money I was earning wasn’t anywhere close to covering my rent and bills. In one week, I worked 36 hours over four days and I should have earned £464 but they gave me £2.74. It doesn’t sound believable but it’s true.
“I was very unhappy delivering for them. Effectively I was paying them to do their deliveries, rather than the other way around.”
Kate Robinson, a Leigh Day employment solicitor, said: "It appears that Amazon is short-changing drivers making deliveries on their behalf.
"Drivers delivering for Amazon have to work set shifts and book time off, yet Amazon claim they are self-employed."
She added that it would be "life-changing" for drivers to get at least National Minimum Wage, holiday pay and a "proper employment contract".
The bill would be a "drop in the ocean" for Amazon, Robinson added.
An Amazon spokesperson said: "We’re hugely proud of the drivers who work with our partners across the country, getting our customers what they want, when they want, wherever they are.
"We are committed to ensuring these drivers are fairly compensated by the delivery companies they work with and are treated with respect, and this is reflected by the positive feedback we hear from drivers every day.”
Sources close to Amazon claim third-party drivers earn at least £120 a day and get a fuel allowance.
