Slow Cooker Roast Beef is tender, flavorful, and hearty—and it comes together with practically no prep time at all! A mouthwatering main dish perfect for holidays or any day of the week.
The crockpot is best known for its ability to transform tough cuts of meat into something tender and juicy, and this slow cooker roast beef recipe is the perfect example.
The slow cooker allows the meat to be cooked at a slow, consistent low temperature, breaking down tough muscle fibers to produce a deliciously tender roast. And of course, we can’t forget about the convenience factor! Just assemble everything in the morning and you’ll have a warm, home-cooked meal waiting for you by dinner time.
Why I LOVE this recipe!
- No Oven Needed – If you need your oven space for cooking side dishes, this slow cooker roast beef is perfect.
- Practically Effortless – There’s so little prep here! Just make the garlic butter, rub it onto the roast, and you’re good to go.
- Family-Friendly – Everyone will love this crockpot roast beef recipe, even the pickiest eaters.
- Leftovers for Days – Slow cooker roast beef makes for delicious leftovers that can be used in sandwiches, salads, or wraps throughout the week. Make sure to check out this huge list of roast beef leftover ideas!
- Holiday Perfect– This dish gives you those scrumptious holiday flavors without taking up more oven space!
This slow cooker roast beef recipe is as simple as promised! Just a few minutes of prep for a family friendly meal.
In this section I am going to go through a few tips and tricks I use for how to make crockpot roast beef to get the absolute best and most delicious results.
Make sure to scroll to the bottom for the FULL recipe card.
Ingredients + Substitutions
- Onions – I use yellow onions, but red or white would also be fine.
- Beef bottom round roast – I recommend a 3 to 4 pound roast. I use this cut because it can cook for an extended period and still be able to be sliced, rather than just fall apart or shred.
Garlic Butter Rub
- Butter – Use unsalted butter if you have it; if you have to use salted, then cut back on the added salt.
- Garlic cloves – Mince these well or, ideally, push them through a garlic press.
- Seasonings – Finely chopped fresh rosemary, dried oregano, kosher salt, freshly ground black pepper, and dried thyme leaves.
Make sure to see the recipe card at the bottom of this post for the full quantities and ingredients list.
What Cut of meat is best for Roast Beef?
The best cut of beef for roast beef is a bottom round roast. This cut comes from the rear end of the cow and it’s known for its flavorful meat that becomes tender when slow cooked. I prefer the bottom round for my crockpot roast beef because it will maintain its shape and you can slice it even after slow cooking for long periods.
If you love this recipe as much as we do and want some quick ways to change it up for variety, these little tips will do the trick!
- Add vegetables – Layer carrots, potatoes, and/or celery in the bottom of the slow cooker with the onions for a complete one-pot meal..
- Try different seasonings – If you have a dry rub you like with beef, you can stir that into the butter, or try your own blend of herbs and spices. Try my ranch seasoning, homemade onion soup mix, or my cajun seasoning for a fun twist!
- Add red wine – If you plan on making gravy, you can pour 1/4 cup of dry red wine (or beef broth) into the cooking juices during the last 30 minutes of the cooking time for a richer flavor. (This will also help loosen any browned bits from the bottom.)
Recipe Step by Step
I am going to highlight a few key steps in the recipe here, but make sure to jump down to the recipe card for comprehensive instructions on how to make slow cooker roast beef.
Combine the butter with the garlic, herbs, and seasonings. Using softened butter makes this much easier and more seamless.
Place the cut onions into the slow cooker and arrange them in an even layer.
Rub the garlic butter mixture onto the beef.
Set the beef on top of the onions.
Cook for 6-8 hours on low, or 4-6 hours on high.
Remove the beef and slice it. Serve with the juices, or whisk them with flour or cornstarch in a pan to make gravy.
- Cook low and slow – While you can definitely cook this on high, the slower cooking time on low heat will result in more tender and flavorful roast beef.
- Dry the roast before adding the garlic butter – This will help the garlic butter rub stick better to the meat.
- Know that the center won’t be red – While roast beef in the oven has that rare center, slow cooker roast beef will not have that same appearance. But trust me, it will still be incredibly tender and flavorful!
- Let it rest – Let the roast rest for 10-15 minutes before slicing into it to ensure the juices set and don’t just run out.
Recipe Short Cuts
If you need to make this recipe, but are extra short on time, here are a few ideas that can help make this recipe even faster!
- Skip the gravy – You can use the juices in the slow cooker to make a gravy, but you can also just spoon the juices over the sliced roast beef for added flavor and moisture.
- Use pre-minced garlic – If you don’t have fresh garlic cloves on hand, you can use pre-minced garlic in the garlic butter rub. Garlic powder is another shortcut option!
- Don’t remove the fat – Instead, just place the fatty side on the bottom of the slow cooker. When the roast is done cooking, it will be easier to remove than removing it while the beef is uncooked.
- Use a liner – To make clean up a breeze, use a slow cooker liner. Simply remove the liner and toss it away after cooking.
Freezer Meal Instructions
Making this slow cooker roast beef recipe into a freezer meal is simple! Follow the steps below and you can store this recipe in the freezer for up to 6 months.
To freeze before cooking
- Prepare the garlic butter rub and apply it to the roast as directed in the recipe.
- Place onions in a freezer-safe bag, then add the roast beef on top. Seal the bag tightly.
- Freeze for up to 3 months.
- Remove the frozen roast from freezer and allow it to defrost in the fridge overnight.
- Place the defrosted roast in the slow cooker on top of the onions and cook as directed in the recipe.
How to Freeze Slow Cooker Roast Beef After Cooking
- Place the roast beef in an airtight container or freezer-safe bag.
- Freeze for up to 3 months.
- When ready to eat, allow the roast beef to defrost in the fridge overnight and reheat in the slow cooker on low for 1-2 hours, in the microwave, or in the oven until heated through.
What to Serve with Slow Cooker Roast Beef
Since this protein based dinner has the delicious flavors of classic home-style meals, it will pair well with many of your favorite old-fashioned side dishes.
Choose one or several of these side dishes to create a wholesome, well-rounded dinner. There are both classic options and some healthy options to keep it light.
Side Dish Ideas
- Pesto Roasted Veggies
- Make Ahead Crockpot Mashed Potatoes
- Instant Pot Baked Potatoes
- Savory Mashed Sweet Potatoes
- Maple Glazed Carrots (pictured)
- Mashed Roasted Cauliflower (pictured)
Slow Cooker Roast Beef Leftovers
If you have leftovers after making this recipe, then it is your lucky day! They save and reheat well, and can make the start of another delicious dish.
To save leftovers, separate into meal sized portions and then place in an airtight container and store:
- in the refrigerator for 3-4 days
- in the freezer up to a month
Here are a few ways to repurpose those leftovers and give them a delicious makeover!
- Roast beef sandwich – Thinly slice the roast beef and place it on your favorite bread or roll. Add some cheese, lettuce, tomato, and any other toppings you like.
- Roast beef sliders – Use the roast beef instead of deli meat for these delicious sliders.
- Roast beef hash – Chop the roast beef and add it to a skillet with potatoes, onions, and your choice of seasonings for a hearty breakfast hash.
- Roast beef salad – Add sliced slow cooker beef roast to your favorite salad for a boost of protein. It would be great in this Grinder Salad!
Do I have to put liquid in the slow cooker with the roast?
No, the slow cooker will create enough moisture as the meat cooks, so there’s no need for additional liquid.
How long can a roast be in a crockpot?
A roast can safely cook in a slow cooker for 6-8 hours on low heat or 4-6 hours on high heat.
Do you have to brown the roast before putting it in the slow cooker?
No, you do not have to brown or sear the roast before putting it in the slow cooker, although you can if you’d like to.
Is it better to slow cook a roast on low or high?
It’s always better to cook roast beef on low, as this will give you the most tender, juicy beef. But sometimes we don’t have time and that’s okay! Your roast will still taste delicious if you have to cook it on high.
More EASY Slow Cooker Recipes
If you enjoyed this recipe, I really hope you will take a moment to grab a few more easy recipes for another busy night!
You can check out all of my easy crockpot recipes here, or see a few of our readers favorite recipes below.
- 3 onions
- 1 beef bottom round roast, 3-4 pounds
Garlic Butter Rub
- ¼ cup butter, softened
- 2 garlic cloves, pressed
- 2 teaspoons finely chopped fresh rosemary
- 1 teaspoon dried oregano
- 1 teaspoon salt
- 1 teaspoon freshly ground black pepper
- 1 teaspoon dried thyme leaves
- Make the garlic butter rub by combining the softened butter with garlic cloves, rosemary, oregano, salt, pepper, and thyme.
- Pat the roast dry with paper towels and then slather the garlic butter mixture over the roast on all sides.
- Quarter the onions and remove the skins and place in the bottom of the crockpot. Position the roast beef on top of the onions fatty side down. Place the lid on the crock pot.
- Cook for 6-8 hours on low, or 4-6 hours on high. Once done, remove the roast beef and thinly slice the meat. Serve with onions and reserve juices to spoon over the top or to make gravy.