The Kiwi driver has been axed by the team after Toro Rosso announced Alexander Albon as the new driver to team up with Daniil Kvyat for the 2019 season.
With Hartley's 2018 teammate Pierre Gasly promoted to the Red Bull Formula 1 team there seemed a chance the Le Mans winner and World Endurance champion would race for a second full season.
The 22-year-old Albon finished third in Formula 2 this year, with a total of four wins.
Hartley finished the Formula One season in 19th on the drivers' championship standings out of 20 drivers. He compiled just four points from the 21 races with a ninth placed finish at the USA Grand Prix his best of the season.
The 29-year-old made his Formula One debut last season at the USA Grand Prix, replacing Gasly for the driver before becoming a fulltime replacement for Kvyat.
He recorded his first Formula One point at the Azerbaijan Grand Prix in April with a 10th placing. Hartley qualified second to last but moved into the top 10 when seven drivers failed to finish the race. The last time a New Zealand driver earned a Formula One point was Chris Amon at the 1976 Spanish Grand Prix.
Hartley followed that up with a 10th at the German Grand Prix in July and a career-best ninth in Austin. He had five retirements from his 21 races this year including a scary crash at the Canadian Grand Prix when he collided with Williams-Mercedes driver Lance Stroll and was pushed into a wall on the opening lap.
It seems unlikely that Hartley will find a drive at another Formula One team next season. All the driving spots are filled expect for one with Lance Stroll expected to be announced as the second Force India driver alongside Sergio Perez.
