To reheat a spiral-cut ham, place it cut-side down on a piece of foil. Wrap the foil around the entire ham. Warm the meat on the upper rack of a 275-degree Fahrenheit oven for 10 minutes per pound.
To help retain moisture, put a shallow pan with water on the lower rack. Before slicing, let the ham stand for 10 minutes. You can reheat smaller portions of spiral-cut ham using the same method. In addition, individual slices warm up well on the stove top in a skillet.
Spiral-cut hams are fully cooked. They typically taste best when served cold. Heating tends to dry out the meat and make glazes run.