Reheating Frozen Ham in the Oven (Internal Temp Guide)

For a fully cooked frozen ham, remove all packaging, place it cut-side down in an oven-safe pan with about ½ cup water, cover, and heat in a preheated oven at 325°F or higher. Reach 140°F for ham from a USDA-inspected plant, or 165°F for other cooked ham and leftovers. Verify in several thick areas with a food thermometer.

A frozen ham can look ready well before the center is safely hot. That can make meal planning feel uncertain, especially when the outside is warming and the clock is ticking. The reliable guide is the thermometer, not color or cooking time. I use the steps below to help make reheating more even and easier to manage.

Pan Selection, Oven Setup & Frozen-Ham Preparation

The right pan and careful preparation help the ham warm evenly and stay moist. Start by checking the ham’s label: this method is for ham marked fully cooked. If it says “cook before eating,” follow its cooking instructions instead, since the reheating temperatures below do not apply.

Choose an oven-safe, nonreactive roasting pan, such as stainless steel, enameled metal, or glass or ceramic cookware rated for your oven temperature. Cookware limits vary, so check the manufacturer’s instructions. There is no single thermal-shock limit for all glass or ceramic pans. In particular, do not place a hot pan on a cold or wet surface.

Before heating:

• Preheat the oven to 325°F (163°C) or higher. Do not use a lower temperature to stretch the reheating time.
• Remove the wrapper, clips, netting, and any absorbent pad. Do not put packaging or a pad in the oven.
• Put the frozen ham cut-side down in the roasting pan. Add about ½ cup water to the pan.
• Cover the ham securely with foil or a fitted lid. Keep the cover from touching an oven element.

If the ham does not fit in the pan, do not force the lid or foil against the oven walls or heating element. Use a suitable larger pan, following its temperature limits.

Covered Reheating, Temperature Checks & Glazing

Covered reheating helps limit moisture loss while the center warms. The oven must be at least 325°F, and the endpoint depends on the ham’s source and packaging. A thermometer reading at the thickest part is the safety check; elapsed time and a browned surface are not proof.

Place the covered pan in the preheated oven. Use the package’s reheating directions and timing when available, allowing extra time because the ham is frozen. As a planning estimate, a frozen ham may take about 1½ times as long as the same ham would take thawed. This is only an estimate, not a safety test.

Start checking before the estimated finish. Insert a food thermometer into the thickest areas, avoiding bone, which can affect the reading. Check more than one spot, especially if the ham is large, irregularly shaped, or bone-in. If any tested area is below the required endpoint, continue heating and check again.

Check the label and packaging history if you are unsure which category applies. A ham sold from a store’s deli or repacked by a retailer may not have the original plant packaging. When the category is uncertain, use the 165°F endpoint.

For a glazed ham, uncover it near the end and apply the glaze then. This gives the surface time to set while reducing the chance that sugar will scorch during a long heating period. Keep checking the thickest areas; the glaze does not change the required internal temperature.

How Long Does Frozen Ham Take in the Oven?

Reheating time varies with the ham’s weight, shape, bone, starting temperature, and oven. Package timing is the best starting point when it is available. Multiply thawed timing by about 1½ only as a rough estimate, then use thermometer readings to decide when the ham is ready.

A smaller, boneless ham may warm sooner than a large bone-in ham, but size alone cannot confirm doneness. Ovens also differ, and opening the door often can slow heating. Keep the ham covered while it reheats, and avoid relying on a single schedule for every cut.

A thermometer is more useful than a precise time estimate because it measures the ham itself. If the first reading is low, return the covered pan to the oven and check again after more heating.

Real-World Frozen-Ham Scenarios

These examples show how to apply the same safety checks to common situations. They are illustrative, not reports from specific households. In each case, the important details are the label, the oven temperature, and thermometer readings in thick areas.

• A whole, fully cooked ham still in its original packaging: Remove all packaging and pads, then heat it covered in a suitable pan. If the label confirms it was packaged in a USDA-inspected plant, aim for 140°F in the thickest areas.
• A ham portion repackaged by a store: The original plant status may be unclear. Treat it as other cooked ham and heat to 165°F, checking more than one thick spot.
• A frozen spiral-cut ham: Keep it covered to help limit drying. Follow its package directions, check the thickest areas, and apply glaze near the end if desired.
• The ham looks done, but the center is below target: Do not serve it yet. Cover it again, continue heating, and recheck the center and other thick areas.

These checks are especially useful when the outside has warmed much faster than the center. Appearance can guide presentation, but only a thermometer confirms the internal temperature.

Safe Cooling, Cleaning & Cookware Care

A hot roasting pan can damage a surface or cookware if it is moved or cooled abruptly. Set the pan on a dry, heat-safe surface and let it cool enough to handle safely. Follow the cookware maker’s directions, especially for glass and ceramic, since thermal-shock limits vary by product.

After cooking:

• Use oven mitts and suitable utensils when moving the pan or ham.
• Do not place hot glass or ceramic on a cold counter, a wet surface, or in the refrigerator.
• Let the pan cool sufficiently before washing it. Avoid sudden temperature changes, including adding cold water to hot cookware.
• Refrigerate leftover ham within two hours. Store it in a covered container and reheat leftovers to 165°F.

If the pan is cracked, chipped, or otherwise damaged, do not keep using it for oven cooking. Check the manufacturer’s guidance for care and replacement.

Carving, Serving & Holding

Once the ham reaches its applicable endpoint, remove it from the oven and carve with clean utensils. A brief rest can make handling easier, but do not treat resting as a substitute for reaching the required temperature. Serve promptly, and keep track of how long the ham and leftovers remain out.

If you are not serving the ham right away, keep it hot rather than leaving it at room temperature. Refrigerate leftovers within two hours. When reheating those leftovers later, use the 165°F endpoint, even if the original ham qualified for the 140°F reheating temperature.

Frequently Asked Questions

These quick answers cover the most common decisions when reheating a fully cooked frozen ham. Check the package for product-specific directions, and use a food thermometer to confirm the center reaches the correct endpoint.

Can I put a fully cooked ham in the oven while it is still frozen?
Yes, if the package allows it. Remove all packaging, use a suitable pan, and allow extra time. Confirm the internal temperature with a thermometer.

What oven temperature should I use?
Use 325°F (163°C) or higher. Do not reheat at a lower oven temperature.

Does every fully cooked ham need to reach 165°F?
No. Ham packaged in a USDA-inspected plant should reach 140°F. Other cooked ham, including repackaged ham and leftovers, should reach 165°F.

How long does frozen ham take to reheat?
It depends on size, shape, and the oven. About 1½ times the thawed reheating time is a rough estimate, not proof that the center is safe.

Should I cover ham while it reheats?
Yes. Cover it with foil or a suitable lid and add about ½ cup water to the pan to help limit drying.

Where should I place the thermometer?
Insert it into the thickest part of the ham, avoiding bone. Check several thick areas, not just the surface.

Can I reheat ham in a glass or ceramic pan?
Only if the cookware is rated for the oven temperature. Follow its instructions, and do not put hot glass or ceramic on a cold or wet surface.

When should I add glaze?
Uncover and glaze near the end of reheating. This helps reduce the chance that the sugar will scorch.

What if the ham is hot outside but below temperature inside?
Keep heating it, covered, and check again in multiple thick areas. Do not rely on color, touch, or elapsed time.

Can I use these directions for ham labeled “cook before eating”?
No. These endpoints are for fully cooked ham being reheated. Follow the package’s cooking instructions for ham that is not fully cooked.

How should I handle leftover ham?
Refrigerate it within two hours. Reheat leftovers to 165°F (74°C) before serving.

The safest plan is straightforward: use a preheated oven at 325°F or higher, keep the frozen ham covered, and treat timing as an estimate. Check the thickest areas with a thermometer and use the endpoint that matches the ham’s packaging.

(This article was written by one of our staff writers, Richard K. Ellison. Visit our Meet the Team page.)