He committed to play college football at the University of Utah over competing scholarship offers from Washington and California.

[5][6] As a junior in 2016, after missing some games due to injury, he returned on November 10 against Arizona State and recorded nine tackles and had an interception in the end zone.

He also attended Utah's Pro Day and opted to only run positional drills for team scouts and representatives.

Head coach Sean Payton officially named him the backup, behind Bell, to begin the regular season.

[25] He made his professional regular season debut and first career start in the Saints' season-opener at the Minnesota Vikings and recorded five combined tackles in their 29–19 loss.

[30] During the season, Williams was used as a third safety in Dennis Allen's three-safety technique and as an extra defensive back in nickel and dime packages.

[35] On September 16, 2018, Williams recorded four solo tackles, deflected a pass, and made an interception during a 21–18 victory against the Cleveland Browns in Week 2.

[36] In week 1 against the Houston Texans, Williams intercepted a pass from Deshaun Watson that was intended for DeAndre Hopkins in the 30–28 win.

[37] In week 4 against the Dallas Cowboys, Williams intercepted a Hail Mary pass from Dak Prescott to seal a 12–10 win.

[38] In week 7 against the Chicago Bears, Williams forced a fumble on rookie runningback David Montgomery which was recovered by teammate A. J. Klein in the 36–25 win.

[44] In Week 1 against the New York Jets, he was the team's leading tackler with 12 combined tackles as well as a 33-yard interception return and a forced fumble.

[49] Despite missing six games overall, Williams still had a solid regular season, finishing with 55 combined tackles, eight pass breakups and an interception.

[50] Williams would reprise his role at starting safety in 2024, but his play regressed significantly, causing the Ravens to have one of the worst passing defenses in the NFL at the beginning of the season.