In 2013, in his senior season, he recorded 102 tackles, including four for loss, one sack and two fumble recoveries, and was named a second-team All-SEC selection.

[10] Throughout training camp, Williamson competed for a roster spot and a role as a backup linebacker against Moise Fokou, Zaviar Gooden, Colin McCarthy, Patrick Bailey and Brandon Copeland.

[11] Head coach Ken Whisenhunt named Williamson the backup inside linebacker behind starters Wesley Woodyard, Zach Brown, and Zaviar Gooden to begin the regular season.

After being relegated to special teams for the first two weeks, Williams was promoted to the reserve inside linebacker on the defense after starter Zach Brown suffered a torn pectoral in the season-opener.

In Week 8, Williamson made a season-high ten combined tackles, broke up a pass, and recorded his first career sack on quarterback Ryan Fitzpatrick as the Titans were defeated by the Houston Texans 30–16.

[17] He was named the starter, along with Zach Brown and outside linebackers Derrick Morgan and Brian Orakpo, to begin the regular season.

[18] On October 11, 2015, Williamson recorded nine combined tackles and made his first sack of the season on Tyrod Taylor during a 14–13 loss to the Buffalo Bills.

He left the game after sustaining a hamstring injury in the fourth quarter and was inactive for the Titans' Week 6 loss to the Miami Dolphins.

[20] On November 15, 2015, Williamson collected a season-high 14 combined tackles (seven solo) and was credited with half a sack on Cam Newton during a 27–10 loss to the Carolina Panthers.

[21] Williamson celebrated his sack on Cam Newton with teammate David Bass by performing a rendition of the dance from rapper Drake's music video "Hotline Bling".

[24] LeBeau retained Willamson and Woodyard as the starting inside linebackers to begin the regular season after Zach Brown departed for the Bills during free agency.

[25] In Week 3, Williamson recorded nine combined tackles, broke up a pass, and intercepted Derek Carr during a 17–10 loss to the Oakland Raiders.

[26] Williamson finished the 2016 season with a career-high 104 combined tackles (73 solo), two sacks, a pass deflection, and an interception in 16 games and 16 starts.

[16] The Tennessee Titans saw significant improvement under their new head coach, going from 3–13 to 9-7 and finishing second in the AFC South, but did not qualify for a playoff berth.

The following week, he recorded nine combined tackles and a pass deflection during the Titans' 35–14 loss at the New England Patriots in the AFC Divisional round.

[29] On January 15, 2018, head coach Mike Mularkey and the Tennessee Titans agreed to part ways after being unable to come to terms on future plans.