Deal will announce his resignation from Congress on Monday, according to the Peach Pundit blog.
Deal's campaign scheduled an announcement for 9 a.m. in Georgia.
The Georgia conservative's resignation would set off a special election in Georgia's 9th congressional district, a heavily Republican district.
Deal's resignation, combined with the retirement announcement of Rep. John Linder (R-Ga.) over the weekend, makes for 21 open seats the GOP will have to defend this fall.
UPDATE 9:14 a.m.: Deal has made it official.