The MOU was signed during a visit by Colombia's President Iván Duque to Chile.
The Spanish telco has already launched the service in Brazil, Colombia, Argentina, Ecuador, Peru and Chile.
The agreement, reached in 2017, states that roaming charges will be scrapped by 2020.
Consultancy OpenSignal looked at how 4G download speeds perform during different times of the day in 77 countries. In nearly half of them speed variation was two times or more.
SAP's Latin America president Claudio Muruzabal said the company is seeing a decoupling of demand for technology in Latin America from macroeconomics as the digital economy takes on a momentum of its own.
The multilateral is financing the acquisition of 600 towers in the South American country to promote infrastructure sharing and reduce the cost of deploying 4G networks.
Telecom Argentina spent nearly US$4mn on the integration.
According to 5G Americas, LTE reached 4bn connections worldwide at the end of 2018, or 47% of all mobile connections. In LatAm, this rate was 40%.