Williams is expected to receive the franchise tag as a defensive tackle, a source told ESPN's Jordan Raanan, confirming a New York Daily News report. The tag number for a defensive tackle is $16.126 million.
The Giants want Williams back and are unwilling to let him leave via free agency, according to Schefter.
The Giants acquired Williams from the New York Jets in a surprise midseason trade, giving up two draft picks.
The Giants thought Williams could be a significant piece for their future. While he improved the run defense and was second on the team behind Markus Golden with 14 hurries despite playing only eight games, Williams managed only 0.5 sacks and two tackles for loss.
Williams, who turns 26 on June 20, was also third on the team behind Golden and Lorenzo Carter with 20 quarterback pressures, according to NFL NextGen Stats. However, it took him 12 games to record a tackle for a loss, and he didn't get a piece of a sack until Week 17.
Williams has 17.5 sacks in five seasons since being selected sixth overall by the Jets in the 2015 NFL draft out of USC. His lack of splash plays helped convince the Jets that he wouldn't be part of their future after he played last year on the fifth-year option of his rookie contract.
He has played in 79 career games with the Jets and Giants, and he has 266 tackles, three forced fumbles and an interception.