Richard has served as the Seahawks defensive coordinator since 2015, with the unit ranking both second and fifth respectively in each of the last two seasons.
He is the fourth coaching candidate the Bills have met with since firing Rex Ryan. General Manager Doug Whaley along with owners Terry and Kim Pegula and Jim Monos have also met with Carolina defensive coordinator Sean McDermott, Bills interim head coach Anthony Lynn and Arizona offensive coordinator Harold Goodwin.
During his end of year press conference Whaley said the franchise is hoping to find a head coach that will be with the team from the next 10-15 years.
At 37, Richard is the youngest candidate the Bills are interviewing for the permanent job in Orchard Park.
In the wild card game against Detroit on Saturday, the Seahawks defense held Matthew Stafford and the Lions to just six points in a 20-point victory for Seattle.
Prior to being promoted to defensive coordinator, Richard was the defensive backs coach for the Seattle from 2012-2014, helping develop Richard Sherman, Earl Thomas and Kam Chancellor.