Hosting a holiday dinner or a Sunday feast often centers around a beautiful, glazed ham. The good news for home cooks is that most hams purchased at the grocery store are already fully cooked. This means your job isn’t actually “cooking” the meat in the traditional sense, but rather reheating it to a safe, delicious temperature without drying it out. Understanding how long to cook pre cooked ham is the difference between a succulent, flavorful centerpiece and a piece of salty leather.
Understanding Your Pre Cooked Ham
Before you set your oven timer, you need to identify exactly what kind of ham you have. Most hams are cured, smoked, or baked before they ever reach the refrigerated aisle.
City hams are the most common variety found in supermarkets. These are wet-cured and usually sold fully cooked. They can be bone-in, boneless, or spiral-sliced. On the other hand, country hams are dry-cured and aged; these require a very different preparation method involving soaking. For the purposes of this guide, we are focusing on the standard fully cooked city ham.
The label is your best friend. If it says “fully cooked,” you can technically eat it cold right out of the package. However, a warmed ham with a caramelized glaze is much more appetizing. If the label says “cook before eating,” you are dealing with a fresh or partially cooked ham, which requires significantly longer cooking times and higher internal temperatures.
The Standard Oven Method
The oven is the most reliable way to reheat a large ham evenly. The goal is to maintain moisture while bringing the internal temperature up to a palatable level.
Preparing the Ham
Start by taking the ham out of the refrigerator about 30 to 60 minutes before you plan to put it in the oven. Taking the chill off the meat helps it heat more evenly. Preheat your oven to 325°F. This lower temperature ensures the outside doesn’t burn or dry out before the center is warm.
Place the ham in a heavy roasting pan. If it is a half-ham, place it cut-side down. This protects the most vulnerable part of the meat from direct heat. Add about a half-cup of water, apple juice, or cider to the bottom of the pan to create a moist environment.
Wrapping for Moisture
The biggest enemy of a pre cooked ham is evaporation. To combat this, wrap the ham tightly with aluminum foil. You can either wrap the ham itself or cover the entire roasting pan tightly with foil. This traps the steam inside, ensuring the meat stays juicy.
Calculating the Time
For a whole bone-in ham, you should plan on 15 to 18 minutes per pound. For a half bone-in ham, it usually takes 18 to 24 minutes per pound. Boneless hams typically heat faster, usually requiring 10 to 15 minutes per pound.
If you are reheating a spiral-sliced ham, be extra careful. Because the meat is already sliced, it loses moisture much faster than a solid roast. These usually need only 10 to 12 minutes per pound at 275°F or 325°F.
How to Use a Meat Thermometer
Time is a great guideline, but temperature is the only way to be certain. Using a meat thermometer is the most important step in the process.
Insert the probe into the thickest part of the ham, making sure it does not touch the bone. For a fully cooked ham that you are simply reheating, the USDA recommends reaching an internal temperature of 140°F. If you are reheating a ham that was packaged in a federally inspected plant, 140°F is the standard. If the ham was “repackaged” or you aren’t sure of the source, aim for 165°F for safety.
Check the temperature about 30 minutes before the estimated time is up. This prevents overcooking, which is the primary cause of a “tough” ham.
Glazing Your Ham
The glaze is where you add your personal touch, but timing is everything. Most glazes contain high amounts of sugar, which burns easily.
Do not apply the glaze at the beginning of the cooking process. Instead, wait until the ham has about 20 to 30 minutes left in the oven. Remove the ham, increase the oven temperature to 400°F, and brush the glaze generously over the surface. Return it to the oven uncovered. You can repeat this process every 10 minutes to build a thick, sticky crust. Keep a close eye on it during this stage to ensure the sugar doesn’t turn from caramelized to burnt.
Alternative Cooking Methods
While the oven is king, there are other ways to heat a pre cooked ham depending on your kitchen setup and the size of the meat.
Slow Cooker Method
If you have a smaller ham or a very large slow cooker, this is a “set it and forget it” dream. It is also the best way to ensure the ham stays moist. Place the ham in the crockpot with a splash of liquid (pineapple juice works beautifully here). Cook on the low setting for 4 to 6 hours. Since slow cookers vary in heat, use your thermometer to check for that 140°F mark.
Air Fryer Method
For a small boneless ham or a thick ham steak, the air fryer is surprisingly effective. Wrap the ham in foil to prevent the fan from drying it out. Heat at 300°F for about 10 minutes per pound. This is ideal for quick weeknight meals when you don’t want to heat up the entire kitchen.
Stovetop Method
If you are cooking ham slices or “steaks” rather than a whole roast, the stovetop is best. Place the slices in a skillet over medium heat with a tablespoon of butter or oil. Cook for 2 to 3 minutes per side until browned and heated through. This provides a lovely sear that you can’t get as easily in the oven.
Resting the Meat
One of the most overlooked steps in cooking any meat is the rest period. Once the ham reaches its target temperature, remove it from the oven and let it sit.
For a large ham, let it rest for at least 15 to 20 minutes. This allows the juices to redistribute throughout the meat. If you cut into it immediately, all that precious moisture will run out onto the cutting board, leaving you with dry meat. Keep the foil loosely tented over the ham during this time to keep it warm.
Troubleshooting Common Issues
Even with the best instructions, things can go wrong. If you find your ham is too salty, you can try soaking it in cold water for a few hours before reheating, though this is usually more necessary for country hams than city hams.
If the ham looks dry when you take it out, don’t panic. Carve the slices and dip them into the juices at the bottom of the roasting pan before serving. You can also serve it with a side of mustard-based sauce or a fruit compote to add moisture and balance the saltiness.
Frequently Asked Questions
Is a pre cooked ham already safe to eat?
Yes, a ham labeled as “fully cooked” or “precooked” has been heated to a safe internal temperature during processing. It is safe to eat cold directly from the package. Reheating it is purely for flavor, texture, and the traditional dining experience. However, if the package says “cook thoroughly,” you must treat it like raw meat and cook it to at least 145°F.
Why did my ham turn out dry even though it was pre cooked?
The most common reason for a dry ham is overcooking or heating it at a temperature that is too high. Since the meat is already cooked, you are simply warming it. If the internal temperature goes well beyond 140°F, the proteins will tighten and squeeze out moisture. Always use foil to trap steam and use a thermometer to pull the ham out exactly when it reaches the target temperature.
How long can I keep leftovers in the fridge?
Once you have reheated and served your ham, leftovers should be refrigerated promptly. Cooked ham will stay fresh in the refrigerator for 3 to 5 days. If you can’t finish it in that time, ham freezes exceptionally well. Wrap it tightly in plastic wrap and then foil, and it will maintain its quality in the freezer for 1 to 2 months.
Can I cook a frozen pre cooked ham?
It is highly recommended to thaw the ham completely in the refrigerator before reheating. Thawing can take 24 to 48 hours depending on the size. If you must cook it from frozen, you will need to increase the cooking time by about 50 percent. For example, a ham that normally takes 2 hours will take 3 hours. You must use a thermometer to ensure the center reaches 140°F.
What is the best liquid to put in the bottom of the roasting pan?
Water is the most basic option and works perfectly to create steam. However, using flavored liquids can subtly enhance the meat. Apple juice, pineapple juice, ginger ale, or even a light beer are popular choices. The liquid helps maintain a humid environment in the oven, which is crucial for preventing the outer layers of the ham from becoming tough.