The resumption of the drills, known as Foal Eagle and Key Resolve, had been a subject of speculation in recent weeks amid the post-Olympics diplomacy between South Korea, a key United States ally, and North Korea.
The exercises could be a first test of the nascent goodwill expressed by the three nations.
They are now scheduled to begin on April 1, according to a Pentagon statement noting an agreement between Defense Secretary James N. Mattis and his South Korean counterpart, Song Young-moo.
The Pentagon said the exercises, which have angered the North in the past, would proceed at a "scale similar" to previous years.
The drills involve live-fire preparations for a possible war with the North, but American and South Korean leaders say they have always been defensive. The North sees them as practice for an invasion.
The North has been notified of the plans, according to the statement.