Dartford won 3-0 at Slough Town, with a double for Charlie Sheringham and a goal for Luke Wanadio seeing Steve King’s side through. They will now face Havant & Waterlooville away from home in the semis.
Also through are Dorking Wanderers, who were 2-1 winners at Bath City. Marc White’s Wanderers led 2-0 at half-time through James McShane and Jason Prior. Jerry Gill’s side came back through a Ryan Brunt penalty but it was not enough.
Dorking will travel to Weymouth for their last-four tie.
In the North Play-Offs Altrincham and Gateshead are through to the final 4.