Jorge Posada won’t be venturing outside The Bronx to extend his major-league career.

A source yesterday confirmed Posada has decided against trying to play in 2012, and will retire a Yankee, made official by a farewell press conference, most likely within the next two weeks.

Posada, who turned 40 in August, was informed by the Yankees earlier this winter he did not fit into their 2012 plans. He had explored the possibility of continuing elsewhere, but with interest limited in his services, he will retire having played his entire career with the Yankees.

The Rays, Orioles and Phillies were among the teams who reportedly had some interest in Posada, who spent last season mostly as a designated hitter.

In 344 at-bats last year, Posada hit .235 with 14 home runs and 44 RBIs. The switch hitter mostly was used as a left-handed batter, after his skills from the right side declined dramatically.

But Posada showed some of his old spark in the Yankees’ AL Division Series loss to the Tigers by going 6-for-14 (.429).

For his career, which began in 1995, Posada hit .273 with 275 homers and 1,065 RBIs. Along the way, he joined Bill Dickey, Yogi Berra, Elston Howard and Thurman Munson in a long tradition of standout Yankees catchers.

Posada’s retirement will mark the second straight year in which the Yankees will say farewell to a core player from the team’s run of four world championships in five years, ending in 2000.

Andy Pettitte — who earned five world championship rings with the Yankees — retired before last season. Derek Jeter and Mariano Rivera are the remaining Yankees players from the team’s last dynasty.

The Yankees drafted Posada as a second baseman in 1990, but moved him to catcher after one minor league season. He made five All-Star teams as a catcher.

Posada’s last contract with the Yankees came following the 2007 season, when he agreed to a four-year deal worth $52 million. He missed most of the following season after undergoing surgery to repair the anterior capsule in his right shoulder. But Posada rebounded and was a key component of the Yankees’ 2009 world championship.

Posada had a turbulent 2011 with the Yankees. After a slow start — which included him asking out of the lineup against the Red Sox after manager Joe Girardi wanted him to bat ninth — there was some question as to whether Posada would survive the year.

But Posada resurrected his season in June by hitting .382 with three homers and 11 RBIs. Before the season, the Yankees signed Russell Martin as their starting catcher and made it clear Posada’s playing time would come from the DH spot.

The Yankees could employ more of a revolving door at DH in 2012, with Alex Rodriguez possibly seeing more at-bats from that spot, depending on his bothersome right knee. Jesus Montero would also figure heavily into the DH equation.