The name is derived from two Common Brittonic words: *penno- (head) and *kēto- (trees), corresponding to modern Welsh pen coed (the place-name Pencoed is found widely in Wales).

Thus the name once meant "end of the wood", suggesting that the parish was at one time on the outskirts of a forest.

It grew due to the crossing over the Mersey at Fiddlers Ferry and the building of the Sankey Canal.

Until the major local government reorganisation of 1974, Penketh was part of Warrington Rural District.

Fiddlers Ferry Power Station dominates Penketh, though it is in Cuerdley parish.

Railway stations in the area include local services from Sankey for Penketh on the Liverpool to Manchester Line (with express services along this route available from Warrington Central), as well as Warrington Bank Quay on the West Coast Main Line.