The deal draws a line under the long-running saga of the site’s ownership.
Balfour bought the airport for £14m in 2008 and invested around £30m in the site during a brief foray into airport ownership.
But the company put it up for sale three years ago with no takers.
Commercial passenger flights have now stopped from Blackpool with the airport used for private aircraft and helicopter flights.
A Balfour Beatty spokesperson said: “The sale of Blackpool Airport further simplifies the portfolio, in line with the Group’s strategy”.
Cllr Simon Blackburn, Leader of Blackpool Council, said: “We do not envisage the return of large scale passenger planes to the airport.
“The purpose of this acquisition is to safeguard the helicopter and other commercial airside activities that take place, build upon them and deliver our overall objective of creating up to 5,000 jobs on the Enterprise Zone site.
“Blackpool Airport is the largest area of land in our thriving Enterprise Zone and this purchase will help us ensure that the airport continues to play a big part in making our Enterprise Zone one of the most successful in the country.
“As the current company stands, Blackpool Airport is profitable and as such we can be confident that the money for the purchase can be repaid.