A self-employed hairdresser from Lancashire has won the right to claim for notice, holiday and redundancy pay.
Meghan Gorman, 26, successfully argued that although she had a contract as a self-employed hairdresser, the amount of control over her working practices effectively made her a salon employee.
Employment tribunal Judge Marion Batten ruled in Ms Gorman's favour.
Ms Gorman's lawyer said many people will be affected by the landmark ruling, as "the significance is huge".
Ms Gorman, from Clitheroe, Lancashire, worked for six years at a Terence Paul salon in Manchester city centre until it closed in 2019.
She claimed she had to work the hours set by the salon, who kept 67% of her takings.
Her lawyers said the judgment furthers recent legal decisions on "worker" status in the case of Pimlico Plumbers at the Supreme Court and Uber drivers, currently on appeal from the Court of Appeal.
Judith Fiddler, of Direct Law & Personnel, said: "The whole hairdressing industry and many others will be affected by this decision.
"The significance is huge, as many people who think they are self-employed are actually not."
'Power and control'
Ms Gorman will now pursue other claims against Terence Paul including unfair and wrongful dismissal, sexual discrimination and a failure to provide a written contract of employment, as well as claiming for holiday pay, her lawyers said.
She joined the business as a 19-year-old trainee in 2013.
Terence Paul claimed the company's self-employed hairdressers had control over the hours and days they worked, their starting and finishing times, treatments they could give and their holidays but Ms Gorman disputed this.
She said: "They clearly had the power and control. I did not believe it could be considered I was in business on my own account."
TUC senior employment rights officer Tim Sharp said "this is yet another case of the courts calling out false self-employment".
Terence Paul has been approached for comment.