Both whole or half, cooked, vacuum-packaged hams and canned hams can be eaten cold, right out of the package.

However, if you want to reheat these cooked hams, set the oven no lower than 325 °F and heat to an internal temperature of 140 °F as measured with a food thermometer.

Spiral-cut cooked hams are also safe to eat cold. The unique slicing method, invented in 1957, reduces carving problems. These hams are best served cold because heating sliced whole or half hams can dry out the meat and cause the glaze to melt and run off the meat. If reheating is desired, hams must be heated to 140 °F as measured with a food thermometer (165 °F for leftover spiral-cut hams). To reheat a spiral-sliced ham in a conventional oven, cover the entire ham or portion with heavy aluminum foil and heat at 325 °F for about 10 minutes per pound. Individual slices may also be warmed in a skillet or microwave.

Cook-before-eating hams or fresh hams must reach 145 °F (with a 3-minute rest time) to be safely cooked before serving. Cook in an oven set no lower than 325 °F. Hams can also be safely cooked in a microwave oven, other countertop appliances, and on the stove. Consult a cookbook for specific methods and timing.

Country hams can be soaked 4 to 12 hours or longer in the refrigerator to reduce the salt content before cooking. Then they can be cooked by boiling or baking. Follow the manufacturer's cooking instructions.

NOTE: Set oven temperature to 325 °F. Cook all raw fresh ham and ready-to-eat ham to a minimum internal temperature of 145 °F as measured with a food thermometer before removing meat from the heat source. For safety and quality, allow meat to rest for at least three minutes before carving or consuming. For reasons of personal preference, consumers may choose to cook meat to higher temperatures. Reheat cooked hams to 140 °F and all others to 165 °F.