Macmahon Holdings Limited was founded by Brian Macmahon, an Adelaide civil engineer, in 1963. It is based in Perth, Western Australia, with offices in Queensland, Northern Territory, South Australia and Malaysia.
The company operates in the Mining and Construction sectors and is listed on the Australian Stock Exchange. It has an annual turnover of about A$850 million.
In June 2008, Macmahon made a hostile takeover bid for rival company Ausdrill Ltd.In January 2013, MacMahon secured its largest ever contract from Fortescue Metals Group after it was awarded a $1.8 billion contract for the Christmas Creek mining operation's expansion. The five-year contract would deliver all aspects of mine operations, including drill and blast, overburden removal, ore harvesting, maintenance of equipment and associated services, for the expansion.Macmahon Holdings also operates in the construction industry under the name Macmahon Contractors. It is unrelated to an Adelaide-based company named McMahon Services.