How to cook prime rib for Christmas: times, temps and two methods

The short answer: how to cook prime rib: salt it early, roast it to temperature rather than time, and rest it before carving.

• How much: a 4 lb bone-in roast for 4 guests
• Two methods: sear first, or reverse sear
• Don't skip the thermometer or carve right away
• A Christmas Day timeline below
• Next step: Plan it with the Christmas Budget & Gift Planner ($4.99).

Prime rib is the showpiece of many Christmas dinners, and it's easier to cook than its price suggests. The keys are simple: salt it early, roast it to temperature rather than time, and rest it before carving. This guide covers how to cook prime rib two ways, a prime rib cooking time chart by size, doneness temperatures, how much to buy and how to plan the day.

What is prime rib?

Prime rib is a beef roast cut from the rib section, also called a standing rib roast. It's the same cut that ribeye steaks come from, but left in one large piece. The fat marbling melts as it roasts, which makes it tender and rich.

For a smaller, leaner roast, see our guide to beef tenderloin, with a temperature chart, cooking times and a reverse sear method.

The word "prime" can mean two things. It often just names the cut. It can also mean the USDA Prime grade, the highest grade, with the most marbling. USDA FSIS's guide to beef explains that Prime, Choice and Select are the main quality grades. FSIS says Prime is only about 2% of graded beef, and most graded beef in supermarkets is Choice or Select. Choice prime rib still roasts beautifully.

How much prime rib to buy

A good rule is 1 rib for every 2 people, or about 1 pound of bone-in roast per person. If you want leftovers, add a rib. Order early in December, since butchers and stores sell out close to Christmas. Ask for the "first cut" or "small end," which is leaner and more tender.

Prime rib doneness temperatures

Always cook prime rib to temperature, not time. Take it out early, because it keeps cooking as it rests.

A note on safety: the FSIS safe temperature chart recommends cooking beef roasts to at least 145°F, then resting them 3 minutes. That is medium. Many families prefer prime rib rarer, which is a personal choice. If you are serving young children, older adults, pregnant guests or anyone with a weak immune system, cook their slices to 145°F.

Method 1: Sear first, then roast

This is the classic method. It's simple and works for any size roast.

1. Salt it early. One or two days ahead, season the roast all over with about 1 teaspoon of kosher salt per pound. Set it on a rack in a pan and refrigerate it, uncovered.
2. Bring it out. Take it out of the fridge about 1 hour before cooking so the center isn't ice-cold. Keep it well inside the FSIS 2-hour limit for perishable food.
3. Season. Rub it with oil or softened butter, black pepper, garlic and chopped rosemary or thyme.
4. Sear. Heat the oven to 450°F. Roast it bone side down for 15 to 20 minutes.
5. Roast. Lower the oven to 325°F. Keep roasting until the thermometer reads 5 to 10°F below your target.
6. Rest. Move it to a board, tent it loosely with foil and rest it for 20 to 30 minutes.

Method 2: Reverse sear

Reverse sear gives the most even pink from edge to center, with a thin brown crust. It takes longer but is very forgiving.

1. Salt the roast 1 to 2 days ahead, as above.
2. Heat the oven to 225 to 250°F.
3. Roast until the center is about 10°F below your target. This can take 3 to 4 hours for a large roast.
4. Take it out and rest it, tented, for 30 minutes to an hour.
5. Heat the oven as hot as it goes, usually 500°F.
6. Return the roast for 8 to 10 minutes, until the outside is deep brown.
7. Carve right away. It has already rested.

Prime rib cooking time chart

These times are for a bone-in roast out of the fridge for about 1 hour, seared at 450°F for 15 to 20 minutes, then roasted at 325°F to medium-rare. They're estimates. Start checking with a thermometer 30 minutes early.

That works out to about 13 to 15 minutes per pound. For medium, add about 10 to 15 minutes. Boneless roasts cook a little faster.

The FSIS beef chart gives longer times because it assumes a roast straight from the fridge cooked all the way to 145°F. It lists a 4- to 6-pound bone-in rib roast at 325°F as about 23 to 25 minutes per pound. If you want medium or are cooking from cold, plan closer to those times.

Buying, storing and thawing the roast

FSIS says to refrigerate a fresh beef roast at 40°F and cook it within 3 to 5 days, or freeze it. If you buy early in December, freeze the roast and move it to the fridge to thaw about 2 to 3 days before Christmas, since large roasts can take 2 days or longer to thaw. Never thaw it on the counter. Don't brown or partly cook the roast and then refrigerate it to finish later. FSIS warns against that because bacteria aren't destroyed.

Common prime rib mistakes

• Skipping the thermometer. Time charts are a guide. A leave-in probe thermometer is the single best tool for prime rib.
• Carving right away. Cut too soon and the juices run onto the board. Rest it.
• Roasting it straight from the fridge. A cold center cooks unevenly. Give it about 1 hour out of the fridge before roasting, well inside the 2-hour limit.
• Covering it. A lid or foil steams the crust. Roast it uncovered.
• Buying too late. Order your roast early in December.

How to carve prime rib

1. Remove the bones. Stand the roast on its side and run a long knife along the bones to cut them away in one piece. Save them to gnaw on or for soup.
2. Turn it fat side up.
3. Slice across the grain. Cut 1/2- to 1-inch slices for serving.
4. Serve on a warm platter. Pour any juices from the board over the top.

What to serve with prime rib

Prime rib is rich, so pair it with simple, bright sides.

For more ideas, our list of Christmas side dishes matches sides to each main and has make-ahead picks.

• Horseradish sauce: 1/2 cup sour cream, 3 tablespoons prepared horseradish, 1 teaspoon lemon juice, salt
• Au jus made from the pan drippings and beef broth
• Yorkshire pudding or popovers baked in the drippings
• Mashed or roasted potatoes
• Roasted green beans, carrots or Brussels sprouts
• A crisp green salad

For a full menu, see our Christmas dinner menu planner. If you're serving ham instead, our guide to how to cook a ham has the times.

A Christmas Day prime rib timeline

Here's a plan for a 6-pound roast and dinner at 5 p.m. using the sear-first method.

• December 23: Salt the roast and set it uncovered in the fridge.
• Christmas, 1:45 p.m.: Take the roast out of the fridge.
• 2:30 p.m.: Heat the oven to 450°F.
• 2:45 p.m.: Roast goes in to sear.
• 3:05 p.m.: Lower the oven to 325°F.
• 4:00 p.m.: Start checking the temperature.
• 4:15 to 4:30 p.m.: Roast comes out to rest. Turn the oven up for Yorkshire pudding or potatoes.
• 5:00 p.m.: Carve and serve.

Leftover prime rib

Leftover prime rib is a treat. USDA FSIS's leftovers guide says to refrigerate leftovers within 2 hours and use them in 3 to 4 days. FSIS's beef guide suggests using frozen home-cooked beef within 2 to 3 months for best quality. Reheat slices gently in a covered pan with a splash of beef broth so they don't overcook. Or skip the heat and slice it thin for sandwiches with horseradish sauce.

Plan and budget your Christmas dinner

Prime rib is often the biggest grocery cost of the holiday, so plan it with the rest of the season. Our Christmas Budget & Gift Planner ($4.99) has a per-person budget, a purchase log and gift, card, menu and to-do pages, so the roast, sides and gifts fit one plan. Our Meal Planner & Grocery List ($3.99) turns the menu into a grocery list. When your prime rib turns out just right, save the method in our Family Recipe Binder ($6.99).