The makers of Big Brother have announced that the show is being axed at the end of the current series.
Big Brother's Twitter account shared the news that the 19th series, launching on Friday night, would be the last.
Channel 5 confirmed Celebrity Big Brother was also ending.
The show first appeared on screens in 2000 and was extremely popular, but viewing figures have dwindled in recent years.
A spokesperson told the BBC: "The forthcoming series of Big Brother will be the last - of either celebrity or civilian versions - on Channel 5.
"We'd like to thank Endemol and all of the production team who have worked tirelessly to make the show a success."
Endemol released a statement shortly after Channel 5's announcement to say they were "disappointed not to reach an agreement with Channel 5" over the future of the show.
The production company did hint that it might not be the end of the show entirely as they added "the decision opens up a new chapter and we are excited about future possibilities for Big Brother in the UK".
During the launch of Celebrity Big Brother, Channel 5 controller Ben Frow hinted the franchise would be ending as "the contract runs out at Christmas".
It was revealed recently by Deadline that Channel 5 was set to bring popular US TV show The Bachelor to a British audience, as a rival to ITV2's Love Island.
The dating show failed to captivate viewers when the channel brought it over in 2012, but the current appetite for dating shows could help revive its popularity.
Big Brother was billed as a social experiment on Channel 4 18 years ago, and involved putting ordinary people in a house over a series of weeks with no contact to the outside world.
Davina McCall presented the first incarnation of the show, stepping down in 2010 when it moved to Channel 5.
It was then hosted by former winner Brian Dowling before Emma Willis took over in 2013 and been narrated by Marcus Bentley for the whole 18 years the show has been on air.
Rylan Clark-Neal has hosted the spin-off show Bit on the Side for six years and tweeted to thank show makers and viewers for the "amazing journey".
The final CBB series was won by Ryan Thomas, but was overshadowed by the actions of Roxanne Pallett, who accused Thomas of punching her.
The incident attracted more than 11,000 complaints to Ofcom and overshadowed the show's other storylines for the rest of the series.
Pallett later apologised to Ryan Thomas, saying she "overreacted".
In July, Endemol Shine UK applied to Hertsmere Borough Council to keep the Big Brother house at Elstree Studios in Borehamwood, Hertfordshire, for the next three years.
The house's current permission was due to expire on 30 September, just 16 days after the new series begins.
The council's planning committee approved the application at a meeting on Thursday, after discussing conditions to restrict noise.