The 37-year-old – who has undergone multiple operations to reconstruct her face and restore her vision after she was the victim of an acid attack by an ex-boyfriend in 2008 – posted a message on Instagram sharing her news.
It comes after the ITV show lost panellists Andrea McLean and Saira Khan.
“It’s official! I’m a @LooseWomen panellist!” Piper told her followers.
“Thank you to everyone for your overwhelming support and kind messages about my recent appearances!
“I can’t wait to become a regular and discuss some wild and wonderful things that the lovely ‘loose’ ladies delve in to! It’s going to be great year, and I can’t wait to take you all along for the ride!”
Piper added on Twitter that she was "so excited" about her new position.
Fans flocked to social media to congratulate the presenter and mental health campaigner.
“So well deserved! Your star is forever rising,” said one person, while another said the star was “perfect” for the role.
“This is brilliant news. You will be incredible,” said another.
Loose Women posted: “We can't wait! Welcome to the family.”
McLean stepped down from Loose Women last year, saying at the time that she had re-evaluated her life due to the COVID pandemic.
Khan followed in her footsteps earlier this year, explaining that she had been reassessing things and that it was time to give up her seat to another woman who would “benefit from the platform as I did”.
Watch: Katie Piper judging child superheroes