There are a few strategies you can use here to heat your ham. The traditional method is to roast the ham at 325 degrees F for 15 to 20 minutes per pound for a whole ham and 18 to 25 minutes per pound for half hams. I prefer to keep this temperature lower and increase the time if I am heating a ready to eat ham. If the ham is a cook before eating then you are best served by starting out with the higher temperature. At the lower temperature your ready to eat ham will cook at about 20 minutes per pound.
Spiral cut hams cook faster since the heat will get in through the slices so for my ham here the cooking time will be around 15 minutes per pound. Since I'm more concerned with heating the ham through and getting a good sugary crust on the outside I will plan on sticking to the time, but won't be too concerned with the final internal temperature.
