The deal brings the mobile crane specialist depot count to 29 across the country and plugs the gap in its national coverage.
West Country Crane Hire was set up 28 years ago by Brian and Donna Metters and serviced the power station and construction industries from five depots in the region.
The hirer boast of fleet of a dozen cranes including a 100t capacity Grove GMK 5100 down to truck and city class machines.
Ainscough managing director Neil Partridge said: “I am delighted to announce our successful acquisition of West Country Crane Hire – the acquisition truly completes our national network.
“The Plymouth site will operate as an Ainscough depot immediately, and we look forward to working with employees, customers and suppliers.”
Brian Metters, managing director of West Country Crane Hire, said: “My wife and I have enjoyed running the business, and we are delighted to be passing it into safe hands.”