Preheat oven to 350°.
Prepare sauce: In a sauce pan add 1 cup of cranberry sauce and 2 jars of sweet chili sauce. Stir and heat until sauce begins to bubble.
Place meatballs in a baking dish (9" x 9") and cover with warm cranberry sweet chili sauce mixture. Place in oven and heat for about 20-30 minutes, or until meatballs are heated through and sauce is hot. Alternatively, use a slow cooker to heat meatballs and sauce, about 5-6 hours on low, or 2-4 hours on high until heated through.