The 23-year-old, comfortable at centre-back and right-back, was a graduate of the Harriers academy after signing his first professional contract in 2013.
He made his first team debut in 2016 and has since gone on to make more than seventy appearances, with loan spells at Hednesford Town, Redditch United and Stourbridge providing him with valuable experience.
Williams has made nineteen appearances for Kidderminster this season and has been a key component in their side that currently sits in seventh place.
Described as a powerful, forward-thinking player, Williams will provide Moors boss Mark Yates with another solid and reliable option in his back line.