The group, which includes affiliates Latam Airlines Peru, Latam Airlines Colombia and Latam Airlines Ecuador, will start operating the new codeshare arrangement in the first quarter of 2020, subject to regulatory approval.
Its current arrangements with American Airlines will come to an end on 31 January next year.
Once the new arrangements with Delta commence, Latam customers will have the opportunity to connect with up to 74 onward destinations in the US and Canada while Delta passengers will have the option of 51 destinations in South America.