When you bring home a fully cooked ham from the grocery store, you have already bypassed the most labor-intensive part of the process. These hams are cured and smoked by professionals, meaning they are technically safe to eat straight out of the package. However, a cold ham rarely carries the same festive appeal as a warm, glistening centerpiece at the holiday table. The real challenge is not “cooking” the ham, but reheating it in a way that preserves its natural juices and enhances its flavor without turning the meat into something resembling shoe leather.
Knowing how long does it take to cook a cooked ham is the difference between a succulent, tender meal and a dry, disappointing one. Because the meat has already been through a cooking process, your oven time is focused entirely on gentle heat penetration. Whether you have a massive bone-in beauty or a convenient spiral-sliced half-ham, understanding the variables of weight, temperature, and moisture is essential for any home cook.
The Standard Rule for Reheating a Fully Cooked Ham
For most store-bought hams, the golden rule of the kitchen is to go low and slow. While it might be tempting to crank up the heat to finish dinner faster, high temperatures are the primary enemy of pre-cooked pork. The USDA recommends reheating fully cooked hams in an oven set no lower than 325 degrees Fahrenheit. At this temperature, the heat is intense enough to penetrate the center of the meat safely but gentle enough to avoid evaporating the moisture from the outer layers.
On average, you should plan for about 15 to 18 minutes per pound for a whole, bone-in ham. If you are working with a boneless variety, that time often increases slightly to 18 to 24 minutes per pound because the meat is denser without the bone to help conduct internal heat. If you are serving a smaller portion, such as a half-ham, the 18 to 24-minute range is a safe bet to ensure the center reaches a palatable temperature.
Variables That Influence Your Cooking Time
Not all hams are created equal, and several factors can shift your timeline by thirty minutes or more. Being aware of these variables allows you to adjust your schedule so the ham is ready exactly when your side dishes are finished.
Bone-In vs. Boneless
A bone-in ham usually heats more evenly. The bone acts as a conductor, helping to move heat into the thickest parts of the muscle. Boneless hams are often pressed into a specific shape, making them more compact. Because the heat has to travel through more solid meat to reach the center, you may find that boneless hams take a few extra minutes per pound compared to their bone-in counterparts.
Spiral-Cut Hams
Spiral-cut hams are a popular choice for their ease of serving, but they require a different approach to timing. Because the meat is already sliced down to the bone, the surface area exposed to the air is much higher. This allows heat to enter the ham faster, often reducing the reheating time to about 10 to 14 minutes per pound. However, this same feature makes them highly susceptible to drying out. If you are heating a spiral ham, keeping it tightly wrapped in foil is non-negotiable.
Starting Temperature
If you take a ham directly from a 38 degrees Fahrenheit refrigerator and put it into a 325 degrees Fahrenheit oven, it will take significantly longer to reach the target internal temperature than a ham that has sat on the counter for 30 to 60 minutes. While you should never leave meat out long enough to reach unsafe temperatures, letting the “chill” come off the ham for about 45 minutes before it hits the oven can shave time off your total bake and lead to more even heating.
Temperature Targets and Food Safety
When reheating a fully cooked ham, you aren’t looking for the 145 degrees Fahrenheit required for raw pork. Instead, the goal is to reach an internal temperature of 140 degrees Fahrenheit. This is the temperature at which the ham is hot enough to be enjoyed but still retains its structural integrity and moisture.
If you are reheating a ham that was not packaged in a USDA-inspected plant—for example, a ham you cooked yourself and are now reheating as leftovers—the safety standard is higher. In those cases, you must reach an internal temperature of 165 degrees Fahrenheit to ensure any potential bacteria introduced during handling are destroyed. For the standard store-bought holiday ham, stick to the 140 degrees Fahrenheit mark for the best culinary results.
Preventing the dreaded Dry Ham
The most common complaint regarding pre-cooked hams is that they end up dry. Since the meat has already been cooked once, every minute it spends in the oven the second time is essentially a gamble with its moisture content. To win this gamble, you need to create a humid environment.
Before placing your ham in the oven, put about half a cup of liquid in the bottom of the roasting pan. Water works fine, but apple juice, orange juice, or even a splash of white wine can add a subtle layer of complexity to the aroma. Once the liquid is in, cover the entire pan tightly with heavy-duty aluminum foil. This traps the steam inside, effectively poaching the ham in a cloud of moisture while it heats.
Another professional tip is to wait until the very end to apply your glaze. Glazes are high in sugar, which burns easily. If you apply a glaze at the beginning of a two-hour reheating process, you will likely end up with a charred exterior and a cold interior. Instead, wait until the ham’s internal temperature hits about 120 degrees Fahrenheit. At that point, remove the foil, brush on your glaze, and return it to the oven uncovered for the final 15 to 20 minutes.
The Importance of the Resting Period
Once the thermometer hits 140 degrees Fahrenheit, your work isn’t quite done. One of the biggest mistakes home cooks make is slicing into the ham the moment it leaves the oven. During the reheating process, the heat pushes the juices toward the center of the meat. If you cut it immediately, those juices will run out onto your cutting board, leaving the slices dry.
Allow the ham to rest for at least 15 to 20 minutes. You can tent it loosely with foil during this time to keep it warm. This resting period allows the muscle fibers to relax and reabsorb the moisture, ensuring that every slice is as juicy as the last. This step also makes the ham much easier to carve, as the meat will hold its shape better under the knife.
Alternative Reheating Methods
While the oven is the traditional choice, it isn’t the only way to warm a pre-cooked ham. If your oven is occupied by rolls and casseroles, you can use a slow cooker.
In a slow cooker, a small or medium-sized ham can be heated on the low setting for about 4 to 6 hours. The enclosed nature of the slow cooker makes it excellent for maintaining moisture, though you won’t get the caramelized exterior that an oven provides. For individual slices, a quick sear in a skillet over medium heat for 2 to 3 minutes per side is often the best way to enjoy leftovers without drying out the entire roast.
FAQs
- How long does it take to cook a cooked ham that is 10 pounds?
For a 10-pound bone-in ham, you should expect it to take between 2.5 and 3 hours in a 325 degrees Fahrenheit oven. A boneless ham of the same weight may take closer to 3.5 hours. Always use a meat thermometer to check the internal temperature rather than relying solely on the clock. - Can I reheat a cooked ham at 350 degrees Fahrenheit?
While you can use 350 degrees Fahrenheit, it increases the risk of the edges becoming tough and dry before the center is warm. It is generally recommended to stay at 325 degrees Fahrenheit for a more even and juicy result. If you do use a higher temperature, reduce the cooking time by about 2 minutes per pound and check the internal temperature frequently. - Do I need to add water to the pan when reheating ham?
Adding liquid is highly recommended. Using about 1/2 cup of water, broth, or fruit juice in the bottom of the pan creates steam when the pan is covered with foil. This prevents the hot air from pulling moisture out of the meat, which is the most common cause of dry ham. - How do I know when a pre-cooked ham is finished?
The ham is finished when it reaches an internal temperature of 140 degrees Fahrenheit. To get an accurate reading, insert a meat thermometer into the thickest part of the ham, making sure the tip does not touch the bone. Touching the bone will give you a false high reading. - Is it safe to eat a fully cooked ham without reheating it?
Yes, a ham labeled “fully cooked” or “ready to eat” is safe to consume cold right out of the package. Reheating is done primarily for flavor, texture, and the comfort of eating a warm meal. If the label says “cook before eating,” however, you must cook it to an internal temperature of 145 degrees Fahrenheit before consumption.