Preparing a ham is often the centerpiece of holiday gatherings, Sunday dinners, and celebratory brunches. However, because most hams sold in grocery stores are already fully cooked, the challenge isn’t actually cooking the meat—it’s reheating it without turning it into a dry, salty brick. Knowing exactly how long for a fully cooked ham to stay in the oven is the difference between a succulent, flavorful feast and a disappointing meal. This guide will walk you through every nuance of timing, temperature, and technique to ensure your ham is the star of the show.
Understanding the Fully Cooked Label
When you browse the meat aisle, you will notice that almost all hams are labeled as “fully cooked,” “ready to eat,” or “city ham.” These hams have been cured in a brine of salt, sugar, and spices, and most have been smoked. This means the meat is technically safe to eat straight out of the package. However, a cold ham isn’t particularly appetizing for a formal dinner.
The goal of “cooking” a fully cooked ham is actually a gentle reheating process. You want to bring the internal temperature up to a point where the fats soften and the flavors bloom, all while maintaining the moisture trapped within the muscle fibers. If you treat a fully cooked ham like a raw piece of pork, you will significantly overcook it, leading to a tough texture.
General Timing Rules for Oven Reheating
The most reliable way to determine how long for a fully cooked ham to heat through is by weight. As a general rule of thumb, you should plan for 10 to 15 minutes of heating time per pound. However, this varies depending on the type of ham you have purchased.
Bone-In Fully Cooked Hams
Bone-in hams are widely considered to have superior flavor and moisture. The bone acts as a conductor of heat from the inside out, but it also adds mass that needs to be warmed. For a whole bone-in ham, which usually weighs between 10 and 14 pounds, expect a total time of 2.5 to 3.5 hours. For a half bone-in ham (7 to 9 pounds), the time usually falls between 1.5 and 2.5 hours.
Boneless Fully Cooked Hams
Boneless hams are easier to slice but can dry out faster because they lack the protection of the bone. These hams are usually smaller, ranging from 3 to 6 pounds. Because they are more compact, they often require about 15 to 20 minutes per pound at a slightly lower temperature to ensure the center gets hot before the exterior becomes leathery.
Factors That Influence Your Timing
While the weight-based estimates provide a great starting point, several variables can shift your timeline. Being aware of these will help you adjust your kitchen schedule accordingly.
The Starting Temperature of the Meat
If you take a ham directly from the refrigerator and put it into the oven, it will take longer to reach the desired internal temperature. To reduce the “thermal shock” and ensure more even heating, many chefs recommend letting the ham sit at room temperature for about 30 to 60 minutes before it goes into the oven. This can shave a few minutes off the per-pound estimate and prevent the outside from overcooking while the middle is still chilly.
Spiral Sliced vs. Whole Surface
Spiral-sliced hams are incredibly convenient because they come pre-cut to the bone. However, those slices create more surface area for moisture to escape. If you are heating a spiral-sliced ham, you must be much more diligent about your timing. These hams generally require less time—often only 10 minutes per pound—because the heat can penetrate the slices more easily. Overcooking a spiral ham by even 20 minutes can result in dry, curled edges.
Oven Temperature Settings
The ideal temperature for reheating a fully cooked ham is 325°F. This is low enough to prevent the sugars in the cure or glaze from burning, but high enough to move the process along efficiently. If you increase the heat to 350°F, you will reduce the time, but you increase the risk of drying out the meat. If you have plenty of time, dropping the oven to 275°F or 300°F is even safer for moisture retention, though it will obviously extend your total duration.
Step by Step Process for Maximum Juiciness
To ensure your timing leads to the best possible result, follow a consistent preparation method. Start by preheating your oven to 325°F. Place the ham in a heavy roasting pan. For bone-in hams, place the flat, cut side down.
One of the best secrets to timing is the addition of liquid. Pour about half a cup of water, apple cider, or orange juice into the bottom of the pan. This creates a steamy environment that protects the meat. The most crucial step is to wrap the pan tightly with heavy-duty aluminum foil. By sealing the ham, you prevent the oven’s dry air from wicking away the juices.
Check the internal temperature about 30 minutes before you expect it to be done. You are aiming for an internal temperature of 140°F. This is the “sweet spot” where the ham is hot enough to be delicious but has not yet begun to lose its structural integrity.
Glazing and the Final Countdown
If you plan to apply a glaze—usually a mixture of brown sugar, honey, mustard, or fruit preserves—you need to account for this in your timing. Do not apply the glaze at the beginning of the process, as the high sugar content will burn long before the ham is hot.
About 20 minutes before the ham reaches 140°F, remove it from the oven and take off the foil. Increase the oven temperature to 400°F. Brush the glaze generously over the surface of the ham. Return it to the oven, uncovered, for 10 to 15 minutes. This allows the glaze to bubble, caramelize, and stick to the meat. Keep a close watch during this stage; the transition from perfectly caramelized to burnt happens very quickly.
Using Alternative Appliances
While the oven is the traditional choice, other appliances change the “how long” equation significantly.
Slow Cooker Method
A slow cooker is excellent for keeping a ham moist. For a small or medium-sized ham, set the slow cooker to “Low.” You will typically need 4 to 6 hours. Because the heat is so gentle and the environment is sealed, the timing is much more forgiving than the oven.
Pressure Cooker (Instant Pot)
If you are short on time, a pressure cooker can heat a fully cooked ham in a fraction of the time. Usually, 2 to 3 minutes per pound on high pressure, followed by a natural release, is sufficient. However, this is only an option for hams that actually fit inside the inner pot, which usually limits you to 3 to 5-pound boneless or “mini” hams.
Resting is Part of the Timing
Once the ham reaches 140°F and you have finished the glazing process, it must rest. Do not skip this step. Remove the ham from the oven and let it sit on a carving board for at least 15 to 20 minutes. During this time, the juices redistribute through the meat. If you cut into it immediately, the moisture will run out onto the board, leaving the meat dry. Account for this 20-minute rest when planning when to sit down for dinner.
Common Mistakes to Avoid
The biggest mistake people make is relying solely on the clock rather than a meat thermometer. Every oven has “hot spots,” and the starting internal temperature of hams varies. If you only look at the clock, you might end up with a center that is still 100°F.
Another mistake is over-wrapping or under-wrapping. If the foil has holes, steam escapes. If the foil is touching a sugary glaze too early, it will stick and pull the delicious crust off when you remove it. Always ensure a “tent” of foil so there is a bit of air space between the metal and the meat surface.
Finally, avoid “checking” the ham too often. Every time you open the oven door, the temperature drops significantly, which can add 5 to 10 minutes to your total heating time for each peek.
Frequently Asked Questions
How can I tell if a fully cooked ham is done without a thermometer?
While a thermometer is best, you can use the metal skewer test. Insert a metal skewer into the thickest part of the ham for 10 seconds, then touch it to your wrist. If it feels very hot, the ham is ready. If it’s just lukewarm, it needs more time. Also, look for the meat beginning to pull away slightly from the bone.
Can I heat a fully cooked ham from frozen?
It is not recommended to heat a large ham from a frozen state. The outside will become dangerously dry and overcooked before the center even thaws. Always thaw your ham in the refrigerator for 24 to 48 hours before you plan to reheat it.
What if I accidentally overcook the ham?
If the ham comes out dry, all is not lost. Slice the ham thinly and serve it with a moistening agent like a warm pineapple glaze, a mustard cream sauce, or even a bit of turkey gravy. You can also simmer the slices briefly in a pan with a little apple juice to rehydrate them.
Is it safe to eat a fully cooked ham cold?
Yes, hams labeled “fully cooked” or “ready to eat” are processed to be safe without further heating. You can slice them for sandwiches or salads directly from the fridge. The reheating process is purely for preference, texture, and flavor enhancement.
How long does leftover cooked ham stay fresh?
Once you have reheated your ham, leftovers should be cooled and refrigerated within two hours. They will stay fresh and safe to eat for 3 to 5 days. For longer storage, ham freezes very well for up to two months when wrapped tightly in plastic wrap and aluminum foil.