Josh Hill is more familiar with the top end of the National League South - narrowly missing out on promotion with Welling United last time out.
The season before that, the 27-year-old gained promotion with Braintree Town.
"We are delighted that Josh has agreed terms for the coming season," Jamie Coyle and Adam Flanagan told the club's website.
"He is a commanding defender that has had great success in the last few seasons, gaining promotion with Braintree and narrowly missing out in the playoff last year at Welling.
"His experience and defensive attributes will add additional competition for places across our back line.”
Dartford fans won't have long to wait to find out their fixtures for next season with the full list released on July 3 2019.