He recorded one interception his senior year, and played in the Maryland Crab Bowl,[1] an all-star game, despite missing most of his season with a finger injury.

On March 19, 2014, Fuller participated at Virginia Tech's pro day, but opted to stand on his combine numbers and only performed positional drills.

[13][14] Head coach Marc Trestman named Fuller the third cornerback on the Bears' depth chart to start the regular season, behind Tim Jennings and Charles Tillman.

[15] He made his professional regular season debut in the Bears' season-opener against the Buffalo Bills and recorded five combined tackles in their 23–20 loss.

On September 14, 2014, Fuller made a season-high seven combined tackles, two pass deflections, and two interceptions during a 28–20 victory at the San Francisco 49ers on Sunday Night Football.

He made his first career interception off a pass by quarterback Colin Kaepernick, that was intended for wide receiver Michael Crabtree, and returned it for a 20-yard gain in the fourth quarter.

[17] In Week 3, Fuller earned his first career start after Charles Tillman sustained a triceps injury and was placed on injured reserve.

[18] He recorded seven combined tackles, two pass deflections, forced two fumbles, and made an interception as the Bears defeated the New York Jets 27–19 on Monday Night Football.

[22] He finished his rookie season in 2014 with 64 combined tackles (51 solo), ten pass deflections, four interceptions, and three forced fumbles in 16 games and 14 starts.

[23] Fuller struggled through the early portion of the season, which included being responsible for two major defensive pass interference penalties, raising the possibility of being moved to safety.

[30] On April 29, 2017, Chicago Bears' general manager Ryan Pace announced that the team would not pick up the fifth-year option on Fuller's rookie contract.

Head coach John Fox named Fuller the third cornerback on the depth chart to start the regular season, behind Cooper and Amukamara.

[32][33] Fuller started in the Bears' season-opener against the Atlanta Falcons after Prince Amukamara injured his ankle during the preseason and was inactive for the first two regular-season games.

[39] Fuller's 2018 season opened on a disappointing note when he dropped a potential game-sealing interception against the Packers, who eventually scored on the drive to win 24–23; after the game, he commented, "All I got to say is I got to catch it.

[42] During the remainder of the regular season, he recorded four more interceptions against Nathan Peterman of the Bills,[43] Matthew Stafford of the Lions,[44] Eli Manning of the New York Giants,[45] and Jared Goff of the Los Angeles Rams.

[49] In Week 2 against the Denver Broncos, Fuller made his first interception of the season off a pass from Joe Flacco that was intended for Emmanuel Sanders in the 16–14 win.

[51] In Week 8 against the Los Angeles Chargers, Fuller recorded a team high 7 tackles and made an interception off Philip Rivers in the 17–16 loss.

[55] In Week 5 against the Tampa Bay Buccaneers on Thursday Night Football, Fuller forced a fumble on running back Ke'Shawn Vaughn which was recovered by teammate Robert Quinn during the 20–19 win.