ACS has agreed with a group of 46 banks to refinance the loan, signed in 2015, and extend its maturity over one year, until December 2021.
The new loan will be divided in two phases, a line A up to €1.4bn and a line B up to €950m.
With this operation, the firm, managed by Florentino Perez, seeks to reduce costs associated with the loan.
In December, ACS completed the sale of its waste division Urbaser with the firm Firion Investments for €1.3bn.