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How Long to Cook a Roast in the Slow Cooker (per lb)

At this time of year, a slow cooked roast is the best kind of comfort food, hearty, warming and delicious! And the best part is that cooking a roast in a slow cooker is really easy. In fact, the only difficult part is figuring out how long to cook a roast in a slow cooker.

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How long to cook a roast in the slow cooker?

How long to slow cook a beef roast

Getting the cooking times right for your slow cooker beef roast can make the difference between melt in the mouth beef or tough or dry beef roast. 

The cooking times will vary according to the size and shape of your roast, what type of roast you have, and whether or not it is bone-in. Then you need to decide do you cook your roast on high or low? 

> Slow cooker beef pot roast recipe

Scroll down for our slow cooker roast beef cooking times calculator, or read on for all the details.  

The best cut of beef for a moist slow cooker roast beef 

If you are after melt-in-the-mouth slow cooker roast beef, the best cuts of beef to use are fatty, tough roasts like the chuck roast or round roast. Chuck beef is the cut you want if you are wondering how to cook melt in the mouth roast beef in a slow cooker.

The slow cooking process helps these roasts get more moist and tender as they cook, unlike leaner roasts, which tend to dry out when cooked in a slow cooker. 

The longer you cook a chuck roast or other fatty, tough roast, the better the results, as the connective tissues (which make it tough) break down in the meat over time.

If you have a leaner cut like a rump roast, sirloin roast, or a rib roast, a quick-cooking method is better. Try searing it in a hot pan with a little oil then roasting it in the oven for 20 minutes per pound, or try this air fryer roast beef recipe

Another consideration when calculating how long to cook a beef joint in a slow cooker is whether or not the roast has a bone. Bone-in roasts usually need a little more time to cook because the bone tends to slow the cooking time as it takes longer to heat up than the surrounding meat.

Is it better to cook a roast on low or high?

Whether to slow cook your beef roast on low or high depends primarily on the cut of beef you are using.

For a fattier cut of meat or one with a lot of connective tissue, cooking slowly on the LOW setting will give you the most tender melt in the mouth roast. A longer cooking time allows the fat and collagen to break down fully and release the juices. 

If you are short on time, cooking on high is fine, but for a really succulent fall-apart roast try to cook it on LOW if you can.

Leaner cuts of meat tend to come out better when cooked on HIGH for a shorter length of time. This is because the longer it’s in the slow cooker, the more time it has to lose moisture.

Slow cooker roast beef cooking times

When a beef roast is cooking the muscle fibers in the meat go through stages of tough to tender to tough again. So getting the timing right can be critical if you want fork-tender beef.  

As the beef cooks, the connective tissues (that make the beef tough) slowly break down into gelatin, and the fat melts into the meat, making the meat succulent and juicy. 

However, if a roast is cooked for too long the fat and gelatin continue to run down through the meat (due to the effect of gravity), and will run out of the meat joint and into the liquid in the slow cooker. The meat fibers then become dried out and tough again.

How long to cook roast in crock pot per pound

The exact cooking times will depend on several different factors including the size and shape of your roast, how hot your slow cooker gets, and how consistent its temperature is. 

Use the guide below to estimate slow cooker beef roast cooking times, but see the section below for details on how to know when your roast is cooked. 

Slow cooker roast beef cooking times calculator1

Beef roast sizeCooking time LOW2Cooking time HIGH3
2-3lb / 1-1.5kg7-8 hours3-4 hours
3-4lb / 1.5-2kg8-9 hours4-5 hours
4-5lb / 2-2.5kg9-10 hours5-6 hours
5-6lb / 2.5-3kg10-11 hours6-7 hours
6-8lb / 3-4kg11-12 hours7-8 hours
Estimated slow cooker roast beef cooking times per lb.
  1. Times are estimates only and will may be different for different makes and models of slow cooker.
  2. Add 30 minutes if the roast is bone in.
  3. Add 20 minutes if the roast is bone in.

How to know when a roast is done in the slow cooker

A simple way to check that your roast is done is to test it with a fork. It should be easy to slide the fork in and pull off a chunk of meat. If the roast is firm and the fork doesn’t really slide in, continue cooking.

To make sure that your beef roast is safely cooked, use a meat thermometer to check that your roast has reached at least 145°F/ 63°C in the center of the thickest part. However, for fork-tender beef roast you will be aiming for around 190-195°F/ 88-91°C (note this is assuming you are using a tough cut of beef, for lean beef aim for 145°F/63°C). 

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Welcome to Love Food Not Cooking!

I’m Eliza, busy mom, home cook, and blogger. My goal is to help everyone cook good food. Whether you are short on time, skills, or motivation, there is something here for you! We have dozens of quick and easy recipes for dinner, lunch, side dishes, and more. Our recipes use everyday ingredients, for quick delicious meals your family will love! Read more…

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