Thousands of Uber, Bolt and Addison Lee drivers are logging off during peak hours on Valentines Day in a campaign for better pay and working conditions, a union says.
The strike action is taking place across the UK from 16:00 to 22:00 GMT.
The Independent Workers Union of Great Britain (IWGB) said it would unite "drivers up and down the country faced with low pay and insecure conditions".
Uber, Bolt and Addison and Lee have defended their working conditions after the IWGB said drivers in cities including London, Birmingham, Manchester, Cardiff and Brighton have backed the strike.
Vasilica Dumitrescu has been working for various platforms, including Uber and Bolt, for the last nine years. The 51-year-old said she works seven days a week, clocking up more than 80 hours, just to make ends meet.
"Its really bad financially, emotionally physically, everything," Ms Dumitrescu said.
"I cant afford to make bills, rent, food, which is so expensive now. Its really, really bad."
Ms Dumitrescu said she hopes the strike leads to higher pay agreements.
"The customers, they are with us," she added. "Every driver is upset because they dont earn enough. They ask you how much you get from this trip and are surprised at how little we get."
An Uber spokesperson said all its drivers are guaranteed to earn at least the national living wage, and that the majority can and do earn more.
"On average, drivers across the UK earn more than £30 per hour when taking trips on Uber," the spokesperson said.
"They also have access to industry-leading protections such as holiday pay, a pension and free sickness and injury cover, as well as formal representation through GMB Union."
A spokesperson for Bolt said the company was "committed to ensuring our prices balance the earning needs of drivers with affordability for passengers".
"All drivers receive holiday pay and monetary supplements to ensure they earn at least the national living wage, alongside a pension," the spokesperson added.
Addison Lee has been contacted for comment. The company previously told the PA news agency: "We have a close working relationship with our drivers, which was further reinforced in our recent bi-annual driver satisfaction survey. We do not expect to see any disruption to volumes or service levels on February 14."
In September 2024, Bolt drivers won a claim against the company after an employment tribunal ruled they were "workers" under UK law and entitled to rights and protections, including the national minimum wage.
In January 2025, Addison Lee drivers won a similar case.
Helio Santos, who is based in Stratford in east London, is another driver taking part in the strike.
He has been driving with Uber for three years and said that while he spent 70 to 80 hours per week online, that often translates to just 25 to 30 hours of driving.
Mr Santos said that Fridays strike action shows that drivers across UK are "reaching a breaking point".
"This is unsustainable," he said. "Fees are too low, there is no safety, no transparency. Uber keeps ignoring us."
Mr Santos, who has three children including a four-year-old, said Ubers promise of the national living wage was "meaningless".
"It is mocking us, saying drivers get a living wage. Ill be better off working for a cleaning company," he added.
The IWGB said that since drivers became "workers" under the law, they have reported their conditions have worsened.
Alongside demands for fairer pay and more secure work, the union is calling for the introduction of safety measures for drivers such as rider ID verification, complaint tracking systems, and support for victims of assault.
Part of Fridays action will include a vigil for Bolt driver Gabriel Bringye who was killed in Tottenham, north London, in 2021.
Mr Bringye, 37, was set upon by a group of teenagers on a crime spree, who booked the cab with the sole intention of robbing the driver.
The IWGB said the vigil marks four years since his death, and that drivers are demanding better protections in his name.