Frankfurt Airport is to spend up to €3bn (£2.2bn) on a new terminal.
The German airport’s owner and operator, Fraport AG, announced it would start construction of Terminal 3 this year.
It said independent studies showed that up to 73M people would use the airport by 2021 – exceeding its current capacity.
The firm said it would use a range of companies for the huge project.
Fraport chief financial officer Matthias Zieschang said: “Terminal 3 will be one of Germany’s largest infrastructure projects.
“Refraining from using a single general contractor for the entire terminal construction, Fraport will instead award targeted multiple contracts to various companies performing specific tasks.”
Fraport will soon issue an EU-wide invitation to tender for the first phase of excavation works on the site.
Terminal 3 is expected to become operational in 2022.