The news went down a storm with viewers, with many who don't usually watch the Channel 4 programme saying they would be tuning in from now on.
"Could not be more chuffed for you, darling," tweeted one.
"Epic news! Y’all gonna send this show interstellar."
It’s Official!! It’s happening The Great British Bake off ! let’s have it - The cake that is 🤣 so excited @BritishBakeOff @Channel4 @PrueLeith @PaulHollywood @noelfielding11 #GBBO pic.twitter.com/IsOlzLGZPh
— Alison Hammond (@AlisonHammond) March 17, 2023
Another wrote: "Absolutely fantastic!! Love this show. Alison and Noel will be the dream team. t’s gonna be soooooo good!!"
"Congratulations to Alison Hammond for being now co presenter of #GBBO and I'm sure she will smash it, said another.
Somebody else tweeted: "I’ve never really watched Bake Off unless on Gogglebox! I will be now."
"I’m actually going to make an effort to watch the next one then," said one person, who added that Hammond would be "amazing".
The TV star's celeb friends also congratulated her after the news was confirmed.
Former Strictly dancer James Jordan said: "This is fantastic news hun - you will be bloody brilliant!!!"
Actor and presenter Sunetra Sarker chimed in: "You are going to smash it babes!
"I love this news xxx."
And Bake Off judge Prue Leith wrote on Instagram: "Huge congratulations Alison, you will be magnificent and I can’t wait for your infectious laugh to be ringing through the tent."
Kate Lawler, who found fame on Big Brother along with Hammond, wrote: "Favourite person on one of my favourite TV shows!!"
"Congratulations beaut," said singer Louise Redknapp.
Lucas stepped down from Bake Off in December after co-hosting for three series.
He said it had been a “delicious” experience but that he was “cheerfully passing the baguette” onto someone else.
Bake Off is due to return later this year with Leith and Paul Hollywood back as the judges.
Watch: Alison Hammond refutes engagement rumours