The Blink-182 drummer popped the question at a beachside hotel in Montecito, Calif.
According to the outlet, the KUWTK star said yes and sealed the proposal with a kiss.
Kardashian also confirmed the news via Instagram, writing, "forever @travisbarker."
Addison Rae exclamimed, "I'M SCREAMING," while Winnie Harlow added, "Ahhhh congratulations."
Barker's daughter, Alabama Barker, wrote, "Love u guys."
The two — who were friends for a long time before they got together — started dating in January. The duo were instantly attached at the hip, as they were spotted with their children and posting on Instagram.
“Kourtney and Travis are doing really well,” a source told Us Weekly. “Kourtney is so smitten with Travis, and everyone around them loves them as a couple.”
In April, Barker gave his lady a special shout-out. “YOU’RE A BLESSING TO THIS WORLD,” he wrote. “HAPPY BIRTHDAY.”
The musician — who was in a plane crash in 2008, which killed four people — also flew for the first time this year, all thanks to the Poosh founder.
“I made a deal with her that she had just said to me, ‘I would love to do so much traveling with you. I want to go to Italy with you. I want to go to Cabo with you. I want to go to Paris with you. I want to go to Bora Bora with you,’” he told Nylon magazine. “And I said, ‘Well, when the day comes you want to fly, I’m telling you I’ll do it with you. I would do anything with you. And just give me 24 hours’ notice.’ And that’s what she did.”
He added, “It’s still something very new to me, but having something that gives me the strength and hope to be able to overcome things that were so traumatic in my life, it just says a ton. She’s definitely that for me. I’m invincible when I’m with her. It’s just like I never dreamed, I never even considered flying again.”
Earlier this summer, a source hinted that the Hollywood stars were in it for the long haul. "An engagement could be right around the corner for Kourtney and Travis," they noted.
In September, Barker wrote on social media, "Laugh with you for the rest of my life."
Sounds like they will be!