The 34-year-old midfielder joins the Breda side on a free transfer and has signed a contract until 2027, making it the tenth club of his professional career for the Erkelenz native.
Holtby announced his departure from relegated Bundesliga outfit Holstein Kiel in the spring. During his career, the veteran played 225 Bundesliga games, 137 games in the Bundesliga 2, 38 in the Premier League and 21 in the Europa League.
In addition to Kiel, he has also played for Hamburger SV, Schalke 04, Tottenham Hotspur and FSV Mainz 05.
"With Lewis, we are gaining a lot of experience for our team. We immediately sensed a connection during the talks, also because he is a real enthusiast and crowd favourite," said NAC's technical director Peter Maas. In the previous season, Breda finished 15th in the league.
NAC Breda continue their Eredivisie campaign this Sunday with a home game against Fortuna Sittard.