The "Something's Gotta Give" singer and her actor-hubby were photographed in Cabo San Lucas, Mexico, locking lips aboard a luxury yacht, Polly, as they joined a female pal and her partner to ring in 2013.
The 30-year-old Rimes and 39-year-old Cibrian spent time relaxing on the boat, worked on their tans and went swimming and jet-skiing among other leisurely activities.
"Whales everywhere yesterday! Such an incredible way to ring in 2013. Happy new year everyone," tweeted the country crooner.
The pair were also without Eddie's sons, who spent the holiday with his ex-wife, Brandi Glanville. Rimes reignited a Twitter war earlier this month with the Real Housewives star when she wrote that Glanville's kids with Cibrian were "my boys."