The B943 is described in the 1922 Road Lists as Branch to Pittenweem Harbour.
It starts on the A917 James Street to the east of Pittenweem town centre. Initially it heads west along Marygate (which is the original line of the A917 through town) before it TOTSOs left onto Abbey Wall Road. In fact, traffic is forced to turn in this way (in both directions) as Marygate beyond this point is one-way eastbound.
The B943 continues south along the residential Abbey Wall Road. It bends to the right on reaching the cliff edge and descends to reach the end of this road and the entrance to the harbour. The B943 ends here and the road ahead, East Shore, is unclassified.