A pre-cooked ham is one of the most convenient centerpieces you can choose for a holiday feast or a Sunday dinner. Because the meat has already been cured and smoked (or boiled), the “cooking” process is actually more of a gentle reheating process. However, the line between a succulent, juicy ham and a dry, leathery one is surprisingly thin. Knowing exactly how long to cook pre-cooked ham, at what temperature, and with which techniques will ensure your meal is a resounding success.
Understanding Your Pre Cooked Ham
Before you preheat your oven, it is essential to understand what kind of ham you have. Most hams sold in grocery stores are labeled as “fully cooked,” “ready to eat,” or “cured.” This means they have already reached a safe internal temperature during processing. Your goal is simply to bring the meat back up to a palatable serving temperature without evaporating all its natural moisture.
There are several varieties of pre-cooked ham, and each affects your timing. A bone-in ham typically retains moisture better but takes slightly longer to heat through to the center. A boneless ham is easier to slice but can dry out faster if overexposed to heat. Then there is the spiral-cut ham, which is pre-sliced all the way to the bone. While convenient, the slices provide more surface area for moisture to escape, requiring a much more delicate approach to reheating.
The Standard Rule for Reheating Times
The general consensus among culinary experts and food safety guidelines is to reheat a fully cooked ham at a low temperature to preserve the texture. A temperature of 325°F is the industry standard for oven reheating.
At 325°F, you should plan for approximately 10 to 14 minutes of cooking time per pound of meat. For a whole ham weighing between 10 and 15 pounds, this could take anywhere from 2 to 3.5 hours. For a smaller half-ham (5 to 7 pounds), you are looking at roughly 1.5 to 2 hours.
If you are using a meat thermometer—which is highly recommended—you are aiming for an internal temperature of 140°F. This is the “sweet spot” where the ham is hot enough to enjoy but hasn’t begun to tighten and lose its juices. If the ham is not “fully cooked” but rather “cook before eating,” you must reach an internal temperature of 145°F and let it rest for three minutes.
How to Cook Pre Cooked Ham in the Oven
To get the best results, you want to create a moist environment inside your roasting pan. Start by placing the ham cut-side down in a baking dish. Add a small amount of liquid to the bottom of the pan—about half a cup of water, apple juice, or cider works beautifully.
The most critical step is wrapping the ham. Use heavy-duty aluminum foil to cover the ham tightly. This traps the steam generated by the liquid and prevents the dry heat of the oven from wicking away the meat’s moisture. If you are cooking a spiral-sliced ham, this step is even more vital because the pre-cut slices are prone to curling and drying out.
Adjusting Times for Different Ham Cuts
Spiral Sliced Hams
Because these are already sliced, they heat up more quickly than solid muscles. You should aim for the lower end of the time spectrum, roughly 10 minutes per pound. Check the internal temperature early to avoid overcooking. If you plan on glazing a spiral ham, do so only in the last 15 to 20 minutes of the process.
Bone-In Hams
The bone acts as a heat conductor once it gets warm, but initially, it adds mass that needs to be penetrated by the heat. Stick to the 12 to 14 minutes per pound rule. The bone-in variety is often considered the most flavorful and is less likely to dry out compared to its boneless counterparts.
Boneless Hams
These are usually compressed into a round or oval shape. Because they are dense, they heat fairly evenly. Usually, 10 to 12 minutes per pound at 325°F is sufficient. These are excellent for sandwiches or smaller gatherings where ease of carving is the priority.
Using a Slow Cooker for Pre Cooked Ham
If your oven is occupied by side dishes or rolls, a slow cooker is an excellent alternative for reheating a pre-cooked ham. This method is inherently “moist,” making it very difficult to dry the meat out.
To use this method, place your ham in the crockpot (you may need to trim it slightly to fit). Add your choice of glaze or a bit of pineapple juice. Set the slow cooker to “Low.” For a small to medium ham, it will take about 4 to 6 hours to reach the desired 140°F. Avoid using the “High” setting if possible, as it can cause the outer edges of the ham to become tough before the center is warm.
The Importance of the Glaze
Glazing is not just about flavor; it acts as a sealant. Most glazes contain sugar, which caramelizes under heat to create a delicious crust. However, because of the high sugar content, glazes can burn easily.
If you are wondering how long to cook pre-cooked ham with a glaze, the answer is: almost the entire time without it, and a very short time with it. You should apply your glaze when the ham has about 20 minutes left in the oven. At this point, remove the foil, brush the glaze liberally over the surface, and increase the oven temperature to 400°F or 425°F for those final minutes. Keep a close watch to ensure the sugar bubbles and browns without turning black.
Resting the Meat
One of the most overlooked steps in cooking a pre-cooked ham is the resting period. Once you pull the ham out of the oven, it needs time to redistribute its juices. If you cut into it immediately, the moisture will run out onto the cutting board, leaving the meat dry.
Tent the ham loosely with foil and let it sit for 15 to 20 minutes. The internal temperature will actually rise by about 5 degrees during this time (a phenomenon known as carryover cooking), so if you pull it out at 135°F, it will perfectly reach 140°F by the time you carve.
Common Mistakes to Avoid
The biggest mistake people make is treating a pre-cooked ham like a raw roast. High heat (above 350°F) for the duration of the cooking time is the enemy. It shrinks the muscle fibers and squeezes out the brine.
Another mistake is forgetting to check the label. If you accidentally buy a “ham shank” or “ham shoulder” that isn’t fully cooked, and you only heat it to 140°F, you may face food safety issues. Always verify that the packaging says “Fully Cooked.”
Lastly, don’t skip the liquid in the pan. Even if you love a “dry” bark on your ham, the meat needs that steam to remain tender. You can always crisp up the exterior at the very end with the glaze and a higher heat setting.
Summary of Reheating Times
- Oven at 325°F: 10-14 minutes per pound.
- Slow Cooker on Low: 4-6 hours total.
- Target Internal Temperature: 140°F.
- Resting Time: 15-20 minutes.
By following these guidelines, you turn a simple piece of grocery store protein into a gourmet meal. Whether it’s flavored with honey, maple, or cloves, the key remains the same: low, slow, and covered.
FAQs
Can I cook a pre-cooked ham from frozen?
It is highly recommended to thaw your ham completely in the refrigerator before reheating. Reheating a frozen ham takes significantly longer (up to 50% more time) and often results in an unevenly cooked product where the outside is dry and the inside is still cold. If you must cook from frozen, use a very low temperature and expect a much longer duration.
Do I need to wash the ham before cooking?
No, you should not wash the ham. Washing meat can spread bacteria around your kitchen surfaces. Simply remove the ham from its packaging, pat it dry with paper towels if you wish to apply a dry rub, and proceed with your reheating method.
Is it safe to eat pre-cooked ham cold?
Yes, since the ham is already fully cooked during processing, it is safe to eat straight from the refrigerator. This is why pre-cooked ham is so popular for deli sandwiches and cold platters. Reheating is purely for preference and to enhance the flavor of glazes.
How do I keep a spiral ham from drying out?
The best way to protect a spiral ham is to wrap it very tightly in heavy-duty foil and place it cut-side down in the pan. This keeps the slices pressed together, minimizing the surface area exposed to air. Using a roasting bag is another effective method to lock in moisture.
How long does leftover cooked ham last in the fridge?
Once you have reheated your ham, leftovers should be stored in an airtight container in the refrigerator. They will remain safe and delicious for 3 to 5 days. For longer storage, you can freeze leftover ham for up to 2 months, though the texture may become slightly softer upon thawing.