A fully cooked ham is one of the most convenient centerpieces you can choose for a holiday feast or a Sunday dinner. Since the meat is already cured and smoked—meaning it is technically safe to eat right out of the package—your goal isn’t actually “cooking” the meat. Instead, your mission is to reheat it so that it stays juicy, tender, and flavorful without drying out into a salty brick.
Understanding the nuances of timing, temperature, and technique is the difference between a succulent meal and a disappointing one. Whether you are dealing with a massive bone-in ham, a convenient spiral-sliced variety, or a small boneless ham, this guide covers everything you need to know about how long to heat up fully cooked ham.
Understanding the Basics of Reheating Ham
Before you preheat your oven, it is important to understand what “fully cooked” means. Most hams found in the grocery store are wet-cured or smoked. This process preserves the meat and makes it safe for consumption. When you put it in the oven, you are essentially performing a “warming” process.
The United States Department of Agriculture (USDA) recommends that a fully cooked ham be reheated to an internal temperature of 140°F if it was packaged in a federally inspected plant. If the ham was not packaged in such a facility or if you are reheating leftovers, you should aim for 165°F to ensure food safety.
How Long to Heat Up Fully Cooked Ham in the Oven
The oven is the gold standard for reheating ham. It provides a steady, dry heat that can be mitigated by proper wrapping to ensure the meat stays moist.
Standard Oven Timing for Bone-In Ham
For a whole or half bone-in ham, the rule of thumb is 15 to 18 minutes per pound. This assumes you are set at a low temperature, usually 325°F.
If you have an 8-pound ham, you are looking at a total time of roughly 2 to 2.5 hours. The bone acts as a heat conductor, helping the center reach temperature, but it also means the meat closest to the bone stays juicy.
Reheating Spiral Sliced Ham
Spiral sliced hams are incredibly popular because the work of carving is already done for you. However, because the meat is already cut, it is much more prone to drying out.
To prevent this, you should heat a spiral ham at 325°F for 10 to 12 minutes per pound. Because the slices allow air to circulate, it heats faster than a solid roast. It is vital to wrap these hams tightly in heavy-duty aluminum foil to trap the steam inside.
Timing for Boneless Ham
Boneless hams are dense and uniform. They generally require 12 to 15 minutes per pound at 325°F. Since there is no bone to help conduct heat to the center, ensure you don’t crank the heat too high, or the outside will become tough before the middle is warm.
Factors That Influence Reheating Time
While “minutes per pound” is a great starting point, several variables can shift your timeline.
Starting Temperature
If you take a ham straight from a 35°F refrigerator and put it into the oven, it will take significantly longer than a ham that has sat on the counter for 30 to 45 minutes to take the chill off. For the most even heating, let the ham sit at room temperature for a short period before beginning the process.
Oven Accuracy
Not all ovens are calibrated equally. An oven set to 325°F might actually be running at 310°F or 340°F. Using an oven thermometer can help you ensure your appliance is performing as expected.
Use of Liquid
Adding a small amount of liquid to the bottom of the roasting pan—such as water, apple cider, or pineapple juice—creates a steamy environment. This can slightly speed up the heating process while acting as an insurance policy against dry meat.
Step-by-Step Instructions for the Perfect Ham
To achieve the best results, follow this tried-and-true method:
- Preheat your oven to 325°F.
- Remove all packaging from the ham. If there is a plastic disk over the bone, make sure to discard it.
- Place the ham in a roasting pan, flat-side down.
- Add about a half-cup of water or fruit juice to the bottom of the pan.
- Cover the ham tightly with aluminum foil. This is the most critical step to prevent moisture loss.
- Bake according to the weight of the ham (usually 15 minutes per pound).
- Check the internal temperature about 30 minutes before the calculated end time using a meat thermometer.
- Once it reaches 135°F, remove the foil and apply any glaze you might be using.
- Increase the oven temperature to 400°F and bake for another 10 to 15 minutes until the glaze is bubbly and the internal temperature hits 140°F.
Alternative Methods for Reheating
While the oven is the most common tool, other appliances can be used depending on the size of your ham and your available time.
Slow Cooker Method
The slow cooker is excellent for smaller boneless hams or ham halves. It is almost impossible to dry out a ham in a slow cooker because the environment is so moist. Set the slow cooker to “Low” and heat for 4 to 6 hours. If the ham is too large for the lid to close, you can create a “tent” out of aluminum foil to seal the top.
Instant Pot or Pressure Cooker
If you are short on time, a pressure cooker can reheat a ham in a fraction of the time. You generally need about 2 to 3 minutes per pound on high pressure, followed by a natural release. However, this method is only suitable for hams that actually fit inside the inner pot without touching the heating elements.
Air Fryer Reheating
For ham steaks or very small portions, the air fryer is a quick option. Heat at 300°F for 5 to 8 minutes. Wrapping the ham in foil is still recommended to keep the edges from becoming “leathery.”
The Importance of the Rest Period
One of the most overlooked aspects of heating up a fully cooked ham is the resting period. Once you pull the ham out of the oven, the residual heat will continue to raise the internal temperature by about 5 degrees.
Allow the ham to rest, covered loosely with foil, for at least 15 to 20 minutes before carving. 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 the meat dry.
Common Mistakes to Avoid
- Overheating: Since the meat is already cooked, every minute it spends in the oven past the 140°F mark is simply removing moisture. Use a thermometer; don’t guess.
- High Temperatures: Do not try to rush the process by setting the oven to 400°F for the entire duration. High heat causes the protein fibers to contract and squeeze out moisture. Low and slow is always better.
- Forgetting the Foil: Unless you are specifically browning the glaze at the very end, the ham should be covered.
- Glazing Too Early: Most glazes contain high amounts of sugar. If you apply the glaze at the beginning of the reheating process, the sugar will burn long before the ham is warm in the middle.
FAQs
- What is the best temperature to reheat a fully cooked ham?
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The best oven temperature for reheating a fully cooked ham is 325°F. This temperature is low enough to prevent the exterior from drying out or burning while being high enough to warm the ham through to the center in a reasonable amount of time.
- How do I know when the ham is done if I don’t have a meat thermometer?
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While a meat thermometer is the most reliable tool, you can check for doneness by inserting a long metal skewer or a thin knife into the thickest part of the ham for 10 seconds. Touch the tip of the skewer to your wrist; if it feels very hot, the ham is likely ready. However, for food safety, a thermometer is always recommended.
- Can I reheat a ham that has already been sliced?
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Yes, but you must be extra careful. Sliced ham loses moisture much faster than a whole roast. Place the slices in a baking dish, add a tablespoon of broth or water, cover the dish tightly with foil, and heat at 325°F for only about 10 minutes or until just warmed through.
- Should I wash the ham before heating it?
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No, you should never wash raw or cooked meat. Washing the ham can splash bacteria onto your kitchen surfaces and does nothing to improve the flavor or safety of the meat. Simply pat it dry with paper towels if there is excess moisture from the packaging before you begin the seasoning or heating process.
- How long can I keep the leftover ham after reheating it?
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Once you have reheated the ham, leftovers can be safely stored in the refrigerator for 3 to 5 days. If you don’t plan on eating it within that timeframe, ham freezes very well. Wrap it tightly in plastic wrap and then foil, and it will maintain its quality in the freezer for up to 2 months.