Whether you are dealing with leftovers from a massive holiday feast or you have purchased a pre-cooked city ham for a Sunday dinner, knowing exactly how long to reheat ham in the oven is the difference between a succulent, flavorful centerpiece and a dry, salty disappointment. Most hams sold in grocery stores today are already fully cooked or smoked, meaning your primary goal isn’t “cooking” the meat, but rather gently bringing it up to an appetizing temperature without stripping away its natural moisture.
Reheating ham is an art of patience. Because ham is lean and often cured, high heat is its greatest enemy. If you rush the process, the exterior will become leathery while the center remains unpleasantly chilly. By following the right techniques regarding temperature, timing, and moisture retention, you can serve a ham that tastes just as fresh as the day it was first glazed.
Understanding Your Type of Ham
Before you set your timer, you must identify the specific type of ham you are working with, as the cut and preparation style significantly impact the reheating duration.
Bone-In vs. Boneless Ham
Bone-in hams generally take longer to heat through because the bone acts as an insulator. However, the bone also helps retain moisture and adds a depth of flavor that boneless varieties sometimes lack. Boneless hams are more uniform in shape, which allows for more even heating, but they are also more prone to drying out because they have more surface area exposed relative to their density.
Spiral Sliced vs. Whole Ham
Spiral sliced hams are incredibly convenient, but they are the most fragile when it comes to reheating. Because the meat is already cut into thin layers, the heat can penetrate the slices quickly, but the moisture can also escape just as fast. Whole or “unsliced” hams have a natural protective barrier that keeps the juices locked inside, requiring a slightly longer time in the oven but offering more forgiveness if you leave them in for a few extra minutes.
Preparing the Ham for the Oven
Preparation is just as important as the reheating time itself. You should never take a ham straight from the refrigerator and put it into a hot oven.
Tempering the Meat
For the best results, let the ham sit at room temperature for about 30 to 60 minutes before reheating. This reduces the “thermal shock” to the meat and ensures that the center reaches the target temperature without the outside overcooking.
The Importance of Moisture
To prevent the ham from becoming “ham jerky,” you must create a humid environment. Place the ham in a heavy-duty roasting pan. Add a small amount of liquid to the bottom of the pan—about a half-cup of water, apple juice, or even white wine works wonders. The liquid will steam inside the oven, keeping the meat fibers supple.
Sealing with Foil
Tightly wrapping the ham or the entire roasting pan with aluminum foil is a non-negotiable step. This traps the steam you’ve created and prevents the dry air of the oven from wicking away the ham’s natural fats and juices. If you are reheating a spiral ham, ensure the foil is wrapped particularly tight around the sliced sections.
General Timelines for Reheating
The standard rule of thumb for reheating a fully cooked ham is to aim for a specific duration per pound. For most hams, the oven should be set to a low temperature, typically 275°F or 325°F.
Reheating at 275 Degrees Fahrenheit
Using a lower temperature like 275°F is the safest way to ensure juiciness. At this temperature, you should plan for 15 to 20 minutes per pound. For a standard 10-pound ham, this means a total time of roughly 2.5 to 3 hours.
Reheating at 325 Degrees Fahrenheit
If you are a bit shorter on time, 325°F is a common standard. At this heat, the timing shifts to approximately 10 to 14 minutes per pound. While faster, you must be more vigilant with your meat thermometer to ensure the internal temperature doesn’t climb too high.
How to Tell When the Ham is Ready
Relying solely on a clock can be risky because oven calibrations vary. The only foolproof way to know how long to reheat ham in the oven is to use a meat thermometer.
The USDA recommends that pre-packaged, fully cooked hams be reheated to an internal temperature of 140°F. If the ham was not professionally packaged (for example, if you are reheating leftovers from a ham you cooked yourself previously), it is safer to bring it up to 165°F. Insert the thermometer into the thickest part of the meat, making sure not to touch the bone, as the bone will give a higher, inaccurate reading.
Adding a Glaze During the Reheating Process
If you plan to apply a honey, brown sugar, or maple glaze, do not do it at the beginning of the reheating process. Glazes have high sugar content and will burn if left in the oven for the full duration.
Instead, wait until the ham is about 20 minutes away from being finished. Remove the ham from the oven, increase the temperature to 400°F, and carefully remove the foil. Brush your glaze generously over the surface and return it to the oven uncovered. This short burst of higher heat will caramelize the sugars and create that signature sticky, delicious crust without drying out the interior.
Tips for Reheating Individual Ham Slices
If you aren’t reheating a whole ham but just a few slices for a quick meal, the oven can still be used, though the process is much faster.
Place the slices in a baking dish, add a tablespoon of water or broth, and cover the dish tightly with foil. At 325°F, individual slices usually take only 8 to 12 minutes to reach a perfect temperature. This method is far superior to the microwave, which often turns ham rubbery and unevenly hot.
Avoiding Common Reheating Mistakes
The most common mistake is overcooking. Since the ham is already cooked, you are essentially “warming” it. Every degree over 140°F (for city hams) begins to squeeze moisture out of the muscle fibers.
Another mistake is forgetting to rest the meat. Just like a steak or a roast, ham needs to rest for 10 to 15 minutes after it comes out of the oven. This allows the juices to redistribute. If you cut into it immediately, the moisture will run out onto the cutting board, leaving the meat dry. Keep the foil loosely tented over the ham during this resting period to keep it warm.
Frequently Asked Questions
Can I reheat a ham at a higher temperature to save time?
While you can technically reheat a ham at 350°F or higher, it is not recommended. Higher temperatures cause the outer layers of the ham to dry out and become tough before the center is even warm. Slow and low is the secret to maintaining the tender texture of the meat.
Do I need to add water to the pan if the ham is already wrapped in foil?
Yes, adding a small amount of liquid to the bottom of the roasting pan creates a “steam oven” effect within the foil. This is particularly important for spiral-sliced hams, which lose moisture more rapidly than whole hams.
How long does it take to reheat a 5 pound ham?
For a 5-pound fully cooked ham at 325°F, it will typically take between 50 and 70 minutes. If you are using a lower temperature of 275°F, it will take approximately 75 to 100 minutes. Always check the internal temperature starting at the 45-minute mark.
Should I keep the ham covered the entire time?
You should keep the ham covered for about 90 percent of the reheating time. The only time you should uncover the ham is during the final 10 to 20 minutes if you are applying a glaze and want to achieve a browned, caramelized exterior.
Is it safe to reheat ham more than once?
While it is technically safe to reheat ham more than once as long as it reaches the proper internal temperature, the quality will degrade significantly each time. The meat will become progressively drier and saltier. It is best to only reheat the portion you plan to eat immediately.