UPDATE 8:35 AM PT
A source in the chapel where they held the ceremony tells us they will only perform it with a marriage license, but a source close to Travis and Kourtney tells us they don’t. haven’t gotten a license, which wouldn’t make it legal.

Kourtney Kardashian and Travis Barker thoroughly enjoyed being in Sin City for the Grammys…having a wedding ceremony in the middle of the night at a wedding chapel…I mean, they’re married!!!

Kourtney and Travis walked into One Love Wedding Chapel around 1:30 a.m. on a Monday … just hours after he performed live at the Grammys. We were told the two didn’t allow the venue to take pictures, instead bringing their own photographer and security.
Sources tell…they had a marriage license and presented it to the chapel owner, who was also a witness.

Sounds like Travis finally found his special someone in Kourtney … remember, he said

“Forever wasn’t long enough” with her.