Thomas entered training camp slated as the starting free safety.
Head coach Pete Carroll named Thomas and Kam Chancellor the starting safeties to begin the regular season.

In Week 8, he collected a season-high ten combined tackles (four solo) during a 34–12 loss to the Cincinnati Bengals.
The following week, Thomas recorded a season-high eight solo tackles in the Seahawks' 23–13 loss at the Dallas Cowboys in Week 9.
On December 27, 2011, it was announced that Thomas was selected to play in the 2012 Pro Bowl, marking the first Pro Bowl selection of his career.
Kam Chancellor and Brandon Browner were also selected to the 2012 Pro Bowl.
He finished the season with 98 combined tackles (69 solo), seven pass deflections, two interceptions, and a forced fumble in 16 games and 16 starts.
Thomas was named second-team All-Pro and was ranked 66th on the NFL Top 100 Players of 2012.
Thomas entered training camp slated as the starting free safety. Head coach Pete Carroll named Thomas and Kam Chancellor the starting safeties to begin the regular season.
In Week 8, he collected a season-high ten combined tackles (four solo) during a 34–12 loss to the Cincinnati Bengals. The following week, Thomas recorded a season-high eight solo tackles in the Seahawks' 23–13 loss at the Dallas Cowboys in Week 9. On December 27, 2011, it was announced that Thomas was selected to play in the 2012 Pro Bowl, marking the first Pro Bowl selection of his career. Kam Chancellor and Brandon Browner were also selected to the 2012 Pro Bowl. He finished the season with 98 combined tackles (69 solo), seven pass deflections, two interceptions, and a forced fumble in 16 games and 16 starts. Thomas was named second-team All-Pro and was ranked 66th on the NFL Top 100 Players of 2012.
Earl Thomas