The B5140 is a short B-road in the northwest of the Wirral.
It starts on the B5139 in Frankby, a surprisingly rural settlement for this part of the Wirral. It heads south along the edge of the cemetery, before having to TOTSO right, on the edge of Roydon Park, to continue along the edge of the cemetery.
The road goes over the top of Montgomery Hill before descending to a roundabout on the A540. It enters Caldy and still appears to be rural, although the buildings start to arrive more frequently. In the centre of the village the road passes the church before bending sharply right and turning into the B5141. Both these roads end here.