Watch: Emma Bunton has married Jade Jones after a 20 year engagement
The 45-year-old 2 Become 1 singer and her partner Jade Jones - former singer with boyband Damage turned chef - have been together for 23 years and have two sons.
Bunton, aka Baby Spice, shared the news on her Instagram account with a picture of the happy couple surrounded by flowers, wearing a white 60s-style mini dress, captioned: "Mr and Mrs Jones!"
Mel B commented: "Yipppeee," along with a kiss emoji and two heart eye emojis.
Victoria Beckham said: "Congratulations love u both so much!!" With a confetti, champagne and balloon emoji.
Mel C replied to the post: "Yeahhhhhh! Congratulations love you all sooooooo much", along with a lot of heart emojis.
Geri Horner, aka Ginger Spice, shared the picture on her Instagram stories, writing: "Congratulations @Emmaleebunton and @JadeJonesdmg So happy for you and your lovely family."
Bunton's close friend TV presenter Holly Willoughby wrote: "Awww my beautiful Baby! Stand up Mrs Jones… love you both…"
Jones - wearing a Gucci blazer, white trousers and brown trilby, shared another picture from the wedding captioned: "Me and Mrs Jones!"
Other celebrities to offer their congratulations included Bunton's Celebrity Juice co-star Keith Lemon, Ant McPartlin and Declan Donnelly, This Morning's Ruth Langsford, All Saints sister Nicole and Natalie Appleton and singer Louise Redknapp.
Lemon commented: "Lovely. Big congratulations. Can I borrow that jacket Jade?"
Britain's Got Talent judge Alesha Dixon commented: "Beautiful Jade! Congratulations."
Nicole Appleton wrote: "Just wonderful!! Congratulations to you all!! Sooo beautiful, sending soo much love."
Bunton's former Heart Breakfast radio co-host Jamie Theakston appeared to be taken surprise by the news, commenting: "Wait … WHAT ?"
The Great British Bake Off presenter Paul Hollywood, Love Island's Laura Whitmore, TV presenter Christine Lampard and reality star Peter Andre also joined in with celebrating the happy couple's big day.
Also chiming in with well wishes were Britain's Got Talent judge Amanda Holden, This Morning's Rochelle Humes, TV presenter Davina McCall, singer and actor Martine McCutcheon, socialite Meg Mathews and Gogglebox star Scarlett Moffatt.
Humes told the couple: "Congratulations beautiful people."
McCutceon exclaimed: "Yay!!! Aaaah so happy for you guys! Fabulous. Congratulations."
Actor Denise Van Outen, I'm A Celeb winner Giovanna Fletcher, ex-EastEnder Tamzin Outhwaite, Ashley Roberts and reality star Vicky Pattison were also among those to offer their congratulations.
Girls Aloud's Kimberley Walsh said: "Congratulations!!!!!!!!! The most gorgeous couple."
Ru Paul's Drag Race judge Michelle Visage commented: "EEEEEEEEEEEE!!!! THIS IS GLORIOUS!"
And McCall wrote: "Awwww that’s such great news!!!!"
Bunton and Jones, 42, have been together since 1998 and became engaged in 2006. They are parents to sons Beau, 13, and Tate, 10.
The Spice Girls star recently published a book about motherhood and admitted she would like to have more children.
Watch: Emma Bunton’s eldest son ordered her to have sex and make another baby!