He will join the club on loan until the end of the season.
The 21-year-old defender is a key acquisition for Vale, and will slot right into the first team. The club released a statement about the move on its official site:
"On behalf of everyone at Port Vale Football Club, we offer him a warm welcome and look forward to seeing him in action."
While Howkins has never started for the first team, he is highly rated by West Brom, and they will be hoping he gets some good experience between now and the end of the season.