Kourtney Kardashian Takes Travis Barker's Last Name on Instagram

Kourtney Kardashian is changing her name to Kourtney Kardashian Barker ... at least on social media ... taking her husband's last name after marrying Travis in Italy.

Kourtney made the name change Monday on her official Instagram page, which now shows Travis' last name tacked on to her name, with a flaming heart emoji.

KKB is still rocking her original Insta handle ... kourtneykardash ... at least for now.

As you know ... Kourtney and Travis got hitched over the weekend in a lavish wedding in Italy, exchanging vows in front of friends and family, including Kim Kardashian and Mark Hoppus.

The wedding was held at the Dolce & Gabbana estate in Portofino. The reception at Castello Brown saw Andrea Bocelli sing as Kourtney and Travis had one of their first dances as husband and wife.

The Italian ceremony was the latest for the lovebirds ... they've also had weddings in Las Vegas and Santa Barbara, and have another celebration planned in Los Angeles.

It will be interesting to see if Kourtney takes Travis' last name legally, or just sticks with it on IG.