The 22-year-old can play at both centre-back and right-back if required.
Smith came through the youth system at Shrewsbury Town and signed his first professional contract in February 2014.
A loan spell at Tamworth followed in the 2014/15 season before further loan spells came at Barrow AFC in 2016 and Southport in 2017.
Smith has also represented Wales at under-19 and under-21 level.
His contract with Shrewsbury was cancelled by mutual consent in March 2018 and he spent the final two months of the 2017/18 season at Telford before signing a new one-year deal at the New Bucks Head ahead of the 2018/19 campaign.