How Long To Cook a Pre-Cooked Ham | Oven Times That Actually Work

A fully cooked ham needs to reach an internal temperature of 140°F–145°F, which takes roughly 10–15 minutes per pound in a 325°F oven—a spongy 10-pound bone-in ham clocks in at about 2.5 hours.

Most hams you buy at the grocery store are already fully cooked, which means you’re really just reheating and glazing, not cooking raw meat. But getting the timing right matters—too hot and you get shoe leather, too short and you’re serving cold ham in the middle of a holiday table. The standard answer for how long to cook a pre-cooked ham in the oven is 10–15 minutes per pound at 325°F, but the exact number depends on the cut, the bone, and your glaze plan. The table below gives you the fast reference.

The Right Internal Temperature Makes the Difference

Since the ham is already cooked, you’re heating it for safety and flavor, not doneness. The USDA says whole pre-cooked hams should reach 140°F–145°F in the thickest part of the meat, then rest for three minutes. Leftover or repackaged ham must hit 165°F because the surface has been exposed to handling.

A good leave-in thermometer is the single best tool here. The ham’s weight gives you a ballpark, but oven accuracy varies—a reliable reading from a probe thermometer stops you from guessing.

When Size Changes the Math

The rule above scales up dependably, but here are real-world examples so you can match your ham’s weight:

• 6-pound pre-cooked ham: about 90 minutes at 325°F.
• 10-pound bone-in ham: 2 to 2.5 hours at 275°F, or about 150 minutes at 325°F.
• 17-pound spiral-cut ham: roughly 4 hours 15 minutes at 325°F.

Weight is the starting point—the thermometer reading is the finish line.

A Step-by-Step Oven Method That Works Every Time

This sequence comes directly from Perdue Farms’ spiral ham guide, and it avoids the two most common failures: dry meat and burned glaze.

1. Preheat the oven to 325°F.
2. Place the ham cut-side down on a roasting rack in a pan. Wrap the whole thing tightly in foil.
3. Cook for 10–14 minutes per pound, or until the internal temperature reaches 100°F–110°F.
4. Remove the foil, pour 1–2 cups of water into the pan (for steam), and return the ham to the oven.
5. When the internal temperature hits 110°F–120°F, take the ham out, apply your glaze, and turn the oven up to 400°F.
6. Roast for 10 minutes, then cook for another 30 minutes, basting 2–3 times.
7. The ham is done at 145°F. the glaze is glossy and caramelized, and the thickest part of the meat reads 145°F on your thermometer.
8. Rest under foil for 25–30 minutes before slicing. This step is non-negotiable—it lets the juices redistribute so every slice stays moist.

Four Tempting Shortcuts That Will Ruin Your Ham

These get mentioned in every holiday thread, and each one has a real downside:

• Cranking the heat above 400°F to speed it up. The meat dries out before the center is warm. Stick to 325°F.
• Glazing too early. The sugar in the glaze burns into a bitter crust before the ham is hot enough. Wait until 110°F–120°F internal temperature.
• Skipping the rest. A ham that goes straight from oven to carving board sheds its juices into a puddle. Ten minutes under foil fixes this.
• Not separating spiral-cut slices when basting. The glaze and moisture just run off the surface instead of reaching the interior layers. Gently separate slices before you brush.

One More Table: Cook Times By Weight At 325°F

Use this second chart as a quick reference for standard pre-cooked hams cooking at the recommended 325°F temperature. All times are for the full cook including the glaze step.

The Checklist That Guarantees a Perfect Ham

Follow this list in order and you won’t need a second try:

1. Remove the ham from the fridge 30–60 minutes before cooking so it starts closer to room temperature.
2. Preheat to 325°F.
3. Place the ham cut-side down on a rack in a roasting pan. Add 1/2 cup water to the bottom of the pan.
4. Cover tightly with foil and bake for 10–15 minutes per pound.
5. Check the temperature in the thickest part—not touching bone—with an instant-read thermometer.
6. When it reaches 120°F, apply the glaze and return the ham uncovered to the oven.
7. Bake until 140°F–145°F for a fully cooked ham, or 165°F for leftover or repackaged ham.
8. Rest under foil for 10–20 minutes before carving.