Campaign officials say Huntsman will endorse Mitt Romney at an event in South Carolina on Monday morning.
Huntsman is scheduled to speak at the Myrtle Beach Convention Center this morning at 11:00 a.m..
The former Utah governor placed third in last week's New Hampshire primary despite devoting much of his campaign resources to the state. He had already acknowledged that expectations for him in South Carolina's primary this week will be "very low."
Huntsman was routinely at the bottom of national polls, barely registering at 1 or 2 percent.
The campaign officials spoke on condition of anonymity because Huntsman plans to make the official announcement Monday.
The Associated Press contributed to this story.
For a list of GOP Presidential candidates schedules, click here.
