Beef
Slow Cooker Prime Rib
Prime rib (also called standing rib roast) already feels like a luxury cut — but roasting it perfectly can be nerve-wracking. This slow cooker version takes the stress out, giving you succulent, evenly cooked beef with a crust and deep…
- Serves 6 – 8
- Prep 20 minutes
- Cook 3 hours
- Total 3 hours

This Slow Cooker Prime Rib Roast is the easiest and best way to cook standing rib roast! Minimum effort and maximum flavor – try my recipe for deliciously tender beef cooked to perfection in your crockpot.
Serve with the perfect Yorkshire Puddings!

Prime Rib Roast (a.k.a Standing Rib Roast) is undoubtedly THE most delicious and spectacular of beef roasts. We always serve it on New Year’s Eve as it is such an amazing roast to share with family and friends.
I have been roasting my rib of beef in the oven for years but this time I decided to cook it in my slow cooker. I was dubious that crockpot prime rib was the way to go, but it was THE BEST we have ever tried! Incredibly succulent beef, tender and with fantastic flavor, what more can you ask for?
Slow Cooker Prime Rib Roast
Prime rib and wing rib are truly special beef cuts. This is reflected in the price, so they are usually reserved for special occasions like Christmas or celebrations.
Cooking such an expensive cut can be intimidating, especially if you have never roasted one before. It can be quite tricky to get the timing just right – inexperienced cooks often overcook the beef ending with a sad, dry roast.
I have certainly made my share of mistakes, which is why I am so thrilled with how incredibly simple it is to cook your prime rib in a slow cooker.

Here’s What You’ll Need
You will need a large capacity slow cooker for this recipe. Check the beef roast fits into your crockpot before attempting this recipe! Smaller roasting joints which can dry out in the oven are ideal for the slow cooker treatment.
- Standing rib roast – either prime rib (fore rib) or wing rib (sirloin). A two rib joint is usually around 2.5kg (5.5 pounds) and should fit a 6+ L slow cooker
- Sea salt and black pepper
- Dried thyme or mixed herbs
- Bay leaves and rosemary
- Onion – I leave the skin on, but you can peel if preferred
- Red wine (or more broth) to deglazing the pan
- Bay leaves and fresh rosemary
- Beef broth (low sodium) or stock
- Vegetable oil
- Xanthan gum or cornstarch to thicken the gravy
- Worcestershire sauce and mustard to flavor the gravy
How to Choose the Right Joint
Prime rib is the same as a Standing Rib Roast or Wing Rib. It usually comes on the bone and a 2-3 rib joint, approximately 5-6 pounds (2-3kg) will serve 6-8. It pays to buy a slightly larger joint if you can afford it as it will shrink slightly as it cooks and you will carve it off the bone. Plus leftovers are to die for!
How to Make Slow Cooker Rib of Beef (Standing Rib Roast)
- Allow the beef to come to room temperature for 30 minutes or up to an hour for a large joint.
- Slice the fat on top of the joint on the diagonal to create a diamond pattern (unless already prepared). Season the beef library with several turns of the salt and pepper mill on all sides and sprinkle with dried thyme.
- Heat the oil in a large skillet and sear the beef over high heat on all sides, using tongs to turn it. Set aside.

- Add the sliced onion to the hot pan and pan fry until colored on both sides. Set aside.
- Deglaze the hot pan with a generous slug of red wine (or you can use Marsala) and cook for a couple of minutes until reduced. Use a wooden spoon to scrape any browned bits loose (all the yummy flavor hides in these!).
- Pour the pan juices into the slow cooker. Add the onion, bay leaves and rosemary. Place the rib joint in the crock pot resting it on the bones with the skin side uppermost. Pour in the beef broth.
- Cover and cook for approximately 3-3 ½ hours on the LOW setting or until the desired temperature is reached on an instant read thermometer (see notes for a guide).
- Rest the beef for a minimum of 20 minutes, loosely covered with foil while you prepare the gravy.

Make the Gravy
- Strain the cooking liquid from the slow cooker into a saucepan. Stir in Worcestershire sauce, mustard and the xanthan gum (or cornstarch slurry). Bring to a simmer, cooking until the gravy thickens. Check the seasoning and adjust if needed.

How to Carve a Rib of Beef
Although I have photographed the beef on the bone while slicing, it is actually easier to separate the bones from the joint before carving.
Remove any string from the joint. Position a sharp knife between the ribs and meat and slice pushing against the bones to release the meat from the ribs. Slice the meat thinly across the grain and serve.

Storing Instructions
Let the beef and gravy come to room temperature. Place slices and gravy in airtight containers and use within 3–4 days. To reheat, place In the oven at low temp (250–270°F / 120–130°C) in a covered dish with a splash of broth to keep it moist. Don’t overheat or you’ll risk drying it out.
Serving Suggestions
Slice thinly across the grain, ideally removing the bones first for easier carving. Serve with the gravy, mustard and horseradish sauce, and a selection of sides such as Yorkshire Puddings, Goose Fat Roast Potatoes, Mashed Potatoes, green bean casserole, Braised Red Cabbage, or Creamy Sprouts With Bacon.

HAVE YOU MADE MY SLOW COOKER PRIME RIB RECIPE? Please leave a rating, post a photo on my Facebook page, share it on Instagram, or save it to Pinterest with the tag #Nusde and make my day!
Recipe
Slow Cooker Prime Rib
This Slow Cooker Prime Rib Roast is the easiest and best way to cook standing rib roast! Minimum effort and maximum flavor – try my recipe for deliciously tender beef cooked to perfection in your crockpot.
- Serves 6 – 8
- Prep 20 minutes
- Cook 3 hours
- Total 3 hours
Ingredients
For the roast
- 5 ½ pounds (2 ½ kg) standing rib roast
- salt and pepper
- 2 tsp dried thyme (or mixed herbs)
- 2 tbsp vegetable oil
- 1 onion (, sliced into rounds)
- ⅓ cup (80ml) red wine (for deglazing the pan)
- 2 bay leaves
- 1 sprig fresh rosemary
- 1 cup (240ml) beef broth (or stock)
For the gravy
- 1 tsp xanthan gum (or see notes)
- 1 tbsp Worcestershire sauce (or soy sauce)
- 2 tsp mustard
- Salt and pepper (, to taste)
Method
Prepare the joint
- 1
Allow the beef to come to room temperature for 30 minutes or up to an hour for a large joint.
- 2
Slice the fat on top of the joint on the diagonal to create a diamond pattern (unless already prepared). Season the beef library with several turns of the salt and pepper mill on all sides and sprinkle with dried thyme. Allow the beef to come to room temperature for 30 minutes or so.
- 3
Heat the oil in a large skillet and sear the beef over high heat on all sides, using tongs to turn it. Set aside.
- 4
Add the sliced onion to the hot pan and pan fry until colored. Set aside.
- 5
Deglaze the hot pan with a generous slug of red wine (or you can use Marsala) and cook for a couple of minutes until reduced. Use a wooden spoon to scrape any browned bits loose (all the yummy flavor hides in these!).
- 6
Pour the pan juices into the slow cooker. Add the onion, bay leaves and rosemary. Place the rib joint in the crock pot resting it on the bones with the skin side uppermost. Pour in the beef broth.
- 7
Cover and cook for approximately 3-3 ½ hours on LOW or until the desired temperature is reached on an instant read thermometer (see notes for a guide). Check the temperature after 3 hours or sooner if you use a smaller joint than the one specified.
- 8
Rest the beef for 20-30 minutes or longer, loosely covered with foil while you prepare the gravy.
Make the gravy
- 9
Strain the cooking liquid from the slow cooker into a saucepan. Stir in Worcestershire sauce, mustard and the xanthan gum (or cornstarch slurry). Bring to a simmer, cooking until the gravy thickens. Check the seasoning and adjust if needed.
Slice and serve
- 10
Remove any string from the joint. Position a sharp knife between the ribs and meat and slice pushing against the bones to release the meat from the ribs.
- 11
Slice the meat thinly across the grain and serve with the gravy and your choice of sides.
Notes
Prime Rib Roast Temperature Chart Check your meat is cooked properly by inserting the thermometer into the middle part of the joint avoiding any bones. Leave for 20 seconds and then check the temperature against the chart below. The “pull from the heat” temperature should be 5-7°F (3-4°C) lower than the final cooking temperatures listed on this chart as the temperature will continue to rise slightly as the beef rests. Rare 120-129°F (49-54°C) Medium Rare 130-134°F (55-57°C) Medium 135-144°F (58-62°C) Medium Well 145-154°F (63-67°C) Well Done 155-164°F (68-73°C) How to thicken the gravy: You can use cornstarch (cornflour) instead of Xanthan gum to thicken the gravy. Dissolve a teaspoon of cornstarch in a little cold water and add to the simmering gravy.
Equipment
- GreenPan Slow Cooker
- Instant Read Thermometer
- Victorinox Carving Set
- Gravy Separator
- Butcher Block
Nutrition
- Calories1266 kcal
- Carbohydrates3 g
- Protein57 g
- Fat111 g
- Saturated Fat46 g
- Polyunsaturated Fat4 g
- Monounsaturated Fat48 g
- Cholesterol251 mg
- Sodium396 mg
- Potassium994 mg
- Fiber1 g
- Sugar1 g
- Vitamin A6 IU
- Vitamin C2 mg
- Calcium42 mg
- Iron6 mg







