The former Hills stars partied up a storm at the Crazy Horse 3 in Sin City on Saturday night (31 August), marking the landmark birthday that happened on 14 August.
Heidi sizzled in a bejewelled mini dress and heels, while Spencer went for a more casual look. Hey, it's his birthday, he can dress how he wants!
Inside the club, Heidi had an extra special present for her husband, emerging from his birthday cake!
The club's official Twitter account shared a photo of the surprise, captioning it: "Nothing better than @heidimontag popping out of a cake for your birthday, right @spencerpratt?"
Spencer already told fans what Heidi got him for his birthday: a retro N64 console! She also threw him a surprise birthday at Don Antonio's in LA. Hills fans will be familiar with the restaurant from all Heidi and Spencer's dates there during the series!
Heidi tweeted: "Happy 30th BIRTHDAY to the love of my life, my hero, inspiration, miracle, angel! The best is yet to come! You are my present every day."
Spencer responded by saying: "The greatest present in the world is having such an AMAZING wife!"
Aww! Despite going through rocky patches, the couple appear stronger than ever and totally loved-up, as we saw during their stint on Celebrity Big Brother earlier this year.