The model and former Big Brother star unveiled a completely new look on Wednesday morning (17 June) after visiting the George Vallossian salon in Knightsbridge, London the previous day.
She said: "Blonde hair don't care. Thanks so much @georgevallossian salon you got it spot on. I love it #nofilter #newhair."
Imogen said she was inspired to go blonde after seeing Khloe Kardashian's lightened locks.
The star is just back home following a sun-drenched and relaxing holiday abroad, which included a friend's wedding in Florence, Italy. (Another Kardashian connection then! That's where Kim and Kanye wed in 2014!)
Imogen and partner Adam Horsley are expecting their second child together in November. They're already parents to adorable daughter Ariana, two.