Adding to the ever-growing list of celebrities who are deciding to bring in the year 2012 with engagements is Justin Timberlake and Jessica Biel, who are….you guessed it….engaged to be married.

After a series of break-ups and make-ups, US Weekly reports that Justin Timberlake and Jessica Biel have finally decided to make their romance official, and get married:

Several insiders tell the new issue of Us Weekly (on stands Friday) that the couple of four and a half years became engaged in late December.

Timberlake, a six-time Grammy winner, popped the question to Biel, 29, in the mountains of Jackson, Wyoming. “Justin knows how much she loves snowboarding and the mountains, so it was the perfect place,” one insider explains.

After a brief three-month split in 2011, Biel made it clear that she wanted to spend her life with Timberlake, 30. “When they reunited, they had a conversation about taking the next step.”

Another Timberlake insider adds that he’s “never been happier” with the New Year’s Eve actress. “He knew it was the right time to propose.”

Congrats Justin and Jessica!

Read up on more about the couple’s engagement, including how Timberlake and Biel told their friends and family they were getting married, in the new issue of US Weekly, which hits newsstands this Friday.

[US Weekly]