Blueberry season is here which means it is time to make blueberry crumble bars! They are buttery, sweet and loaded with fresh fruit. 

stack of three blueberry crumble bars sitting on a white round plate

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I love the ease of dessert bars. It is just so simple to make a big tray of blueberry crumble bars, cut them into perfect pieces, then serve them to my friends and family. You don’t even need plates when you make bars! Just pick them up and enjoy every bite. A delicious bar is a perfect, mess-free treat. 

blueberry crumble bars cut into squares sitting in a 9x13 baking dish

Blueberry Crumble Bar Recipe

I am a big fan of blueberry desserts. Anytime blueberries are on sale, I always grab a bunch so I can make blueberry buckle, blueberry cobbler, and fresh blueberry pie. Blueberry crumble bars may just be my favorite blueberry dessert of all. The buttery crust melts in your mouth and the fresh berries are bursting with the flavor of summer. 

To make my easy blueberry bar recipe, you begin with the crust and crumble topping. A mix of butter, flour, sugar, and spices creates the crust and topping in just one easy step. The blueberry filling is just as easy to make, so your crumb bars are in the oven in less than 10 minutes. The result is a beautiful tray of blueberry crumb bars that is enough for about twelve people (or enough for you to have dessert for yourself for the week!). Any blueberry lover needs to give this crumble bar recipe a try. It is simple, sweet, and a great way to celebrate blueberry season!

ingredients for crumble mix for blueberry crumble bars
blueberry mixture layer ingredients to blueberry crumble bars

Blueberry Crumble Bars Recipe

See recipe card below this post for ingredient quantities and full instructions.

  • Flour – Regular all-purpose flour works best! 
  • Sugar
  • Baking Powder
  • Salt
  • Cinnamon – A little bit of cinnamon adds some serious flavor to the blueberry bars. You can skip the cinnamon if you aren’t a fan of the taste. 
  • Egg
  • Vanilla
  • Butter – Use unsalted butter for this recipe. There is already the perfect amount of salt added to the crumble. You don’t want too much!
  • Cornstarch – Cornstarch will help thicken the blueberry filling as it bakes.
  • Sugar
  • Lemon juice – One large lemon will give you enough juice for this recipe. 
  • Lemon zest – You may need two lemons to get enough zest for the bars. 
  • Fresh blueberries – Fresh berries definitely work best in this recipe. They have the perfect amount of juice to make the bars moist and flavorful. 


Here are a few ingredient substitutions and variations that may work well. 

  • Use frozen berries in place of fresh ones. Measure the 4 cups of frozen berries while they are still frozen solid. Make the filling with cold berries. You do not want to thaw them or the filling will become runny and watery. 
  • Replace the cornstarch with two tablespoons of flour. Flour is a good alternative to cornstarch that will still thicken the filling perfectly. 
  • Use lime juice and lime zest in place of lemon. This will make tangy, sweet blueberry crumble bars that are delicious in summer. I like the lime version on super hot days. There is something about lime that is just so refreshing! 
  • Replace the flour with a gluten-free flour baking mix. This bar recipe will be delicious as gluten-free blueberry bars. 

How to Make Blueberry Crumble Bars

  1. Prepare: Preheat the oven to 375ºF, then grease a 9×13 pan with baking spray or butter. 
  2. Make the crust: Mix the flour, baking powder, cinnamon, and salt together. Add the egg, vanilla, and cold butter. Use your hands, a pastry blender, or a fork to mix everything together, making coarse crumbles. Pour half the mix into the greased 9×13 pan and put the other half of the mix aside. Press the crust into the pan, making an even, flat layer in the bottom. 
  3. Make the filling: Mix all of the filling ingredients together in a large bowl. Pour the filling on top of the crust in the 9×13 pan. Spread the blueberries into a flat layer inside the pan. 
  4. Add the crumble: Sprinkle the remaining crumb mix over the berries. 
  5. Bake: Bake the bars for about 40 minutes. The crumble will be brown and the berries will be bubbling around the edges. 
  6. Cool: Let the bars cool for at least 30 minutes before slicing and serving. 
top down image of a square serving of blueberry crumble bar with a forkful of the dessert sitting on a white round plate

Quick Tip

These blueberry crumble bars definitely slice best when they are very cold. If you want perfectly shaped bars, with clean edges, put the tray of bars in the fridge to cool before cutting. Warm bars tend to crumble and not look quite as pretty (but they will still taste great!). Chilling the bars is important!

How to Store Blueberry Crumble Bars

Once your blueberry crumble bars have cooled, you can store them at room temperature in an airtight container for 2-3 days. Place the container in the fridge and the bars will keep for about a week. I like the texture of the room temperature bars best but, if I want them to last longer, I always stick them in the fridge!


Can I use frozen blueberries instead of fresh?

Yes! You can use frozen blueberries in place of fresh berries. Just be sure to measure the berries when they are frozen and firm. Measuring them when soft and thawed will add too many berries to the filling and make it watery. But frozen blueberries will be great!

Can I use other types of fruit?

Yes! You can use this blueberry crumble bar recipe to make other types of crumble bars as well. Raspberry, strawberry and even blackberry crumble bars will all be delicious!

Why did my blueberry bars stick to the pan?

If your bars are hard to get out of the pan, the baking dish probably wasn’t greased enough. Try heating the bars in the oven for a minute or two to soften the filling and help release the bars from the pan. You can also line your pan with parchment paper next time you make this recipe to help them come out easily.

More Easy Dessert Recipes

Blueberry Crumble Bars

Blueberry season is here which means it is time to make blueberry crumble bars! They are buttery, sweet and loaded with fresh fruit.
4 from 1 vote
Course: Dessert
Cuisine: American
Servings: 12 servings
Prep Time: 15 minutes
Cook Time: 40 minutes
Cooling Time: 30 minutes
Total Time: 1 hour 25 minutes



  • 3 cups flour
  • 1 cup sugar
  • 1 teaspoon baking powder
  • 1/4 teaspoon salt
  • 1/2 teaspoon cinnamon
  • 1 egg
  • 2 teaspoons vanilla extract
  • 1 cup butter cold, cubed


  • 1 tablespoon cornstarch
  • 1/2 cup sugar
  • 1 teaspoon lemon zest
  • 4 cups fresh blueberries
  • 2 tablespoons lemon juice


  • Preheat the oven to 375 degrees F and grease a 9×13 baking pan with butter. Set the pan aside for now.
  • Start by making the crust/crumble mix. Add the flour, sugar, baking powder, cinnamon and salt to a large bowl and stir together.
  • Add the egg, vanilla, and cold cubed butter to the bowl. Use a fork to mix everything together until it is evenly blended and looks like coarse crumbles. You can also mix with your hands, rubbing the butter into the dry flour mix.
  • Pour half of the flour mixture into the greased baking pan. Spread the mix across the bottom pan to form an even layer then press down to make a firm crust. Set aside for now.
  • Next, make the filling. In a separate large mixing bowl,  whisk the cornstarch, sugar, and lemon zest together. Add the blueberries and lemon juice and toss everything, mixing well.
  • Pour the blueberry filling over the crust in the pan and spread it into an even layer.
  • Sprinkle the remaining flour mix over the top of the blueberry filling, making an even crumble topping.
  • Bake the bars for 40 minutes. The top will be a nice golden brown.
  • Let the bars cool in the pan for at least 30 minutes before cutting and serving.


Calories: 385kcal | Carbohydrates: 57g | Protein: 4g | Fat: 16g | Saturated Fat: 10g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 4g | Trans Fat: 1g | Cholesterol: 54mg | Sodium: 177mg | Potassium: 119mg | Fiber: 2g | Sugar: 30g | Vitamin A: 520IU | Vitamin C: 6mg | Calcium: 30mg | Iron: 2mg
Did you make this recipe?Mention @kasey_allthingsmamma or tag #allthingsmamma!

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About Kasey Schwartz

For over 15 years, Kasey Schwartz, the mastermind behind All Things Mamma, has been the ultimate go-to for mouthwatering family recipes. Her work has been featured on, Buzz Feed, Better Homes and Gardens, and more, making her your go-to mom next door for all things delicious and family-friendly.


  1. 4 stars
    The filling for this recipe is delicious, especially with fresh picked blueberries! Next time I make it, I will make sure I have cornstarch, because I substituted flour to thicken it and it was a little too floury for my taste with the crust. Also, I might add a little extra butter to the (2.5 sticks, not just 2) to the crust mixture. Mine did not really look like the recipe photo, so perhaps I did something wrong? Full disclosure I’m not a very good baker, so this could be a me problem 😆!

  2. Hi im going to make this crumble it looks so good . Thank you

  3. Hi kasey can I use frozen blueberries to make the blueberry bars

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