The pair, who have been friends for 10 years, shared their happy news in the forthcoming marriages section of The Times on Tuesday.
Ollie then posted a picture of the page alongside a sweet tribute to his fiancé, saying that he “said yes on Sunday” and joking about already having the same surname.
He wrote: “I have known him for 10 years, and at many of my most important life moments he was in the background.
“Earlier this year we realised that what we had both been looking for was standing in front of us all along, the greatest hint was probably that we already have the same surname!”
Ollie, 30, added that he had “never been happier” and couldn’t wait for the “rest of his life with someone who makes him smile every day”.
He also shared the announcement on his Instagram story, drawing a pink heart around the notice writing “I thought you should know x”.
Fans rushed to congratulate the E4 star, who have appeared on other reality shows including Celebs Go Dating and Celebrity Island, on his engagement.
One wrote: “Congratulations. After kissing frogs you finally found your king xxxx.”
While another said: “Congratulations you beautiful people! Lovely news! Wishing you a lifetime of of happiness... xxx,” alongside champagne and heart emojis.
“Congrats darl! Married life is the absolute best! So thrilled for you x biggest engagement kisses,” said somebody else.