This Post May Contain Affiliate Links. Please Read Our Disclosure Policy.

Easy keto lemon bars are a low carb take on a classic lemon dessert, made with a handful of keto pantry staples. This sugar-free dessert bar features a tart-yet-sweet lemon filling baked on top of a rich, buttery shortbread crust, all for just 2 net carbs per square. Perfect for cookouts, baby showers, Easter, or Mother’s Day, and guaranteed to satisfy any sweet tooth.

A stack of 4 keto lemon bars against a white background

🍋 What Makes This Recipe So Good

  • Like traditional lemon bars, this keto version layers a tangy, gooey lemon filling on top of a rich, buttery shortbread base and finishes it off with a dusting of powdered sugar. Of course, since it’s keto, our shortbread base is made from almond flour, and the powdered sugar is really powdered erythritol. You’d never know that if I hadn’t told you, though! They’re every bit as delicious as (and maybe even better than?!) a classic lemon bar, without all the sugar and gluten.
  • These dessert bars are a lemon lover’s DREAM! We use allllllll parts of the lemon here – lemon zest in the crust, lemon juice in the filling, and a little lemon slice garnish on top. It’s tart and citrusy, but totally balanced out by the shortbread and sweetener. Every bite just screams “springtime”!
  • If you’re not tempted to eat the entire pan of lemon bars in one sitting (sorry, not sorry) then they’re a great make-ahead option! Store them in the fridge in an airtight container and they’ll last up to 1 week. You can even freeze them up to 6 months if you want – just keep them in a sealable bag or other airtight container.

👩🏼‍🍳 Chef’s Tips

  • When you’re zesting your lemons, be careful to only get the bright yellow lemon peel! The white pith below it is super sour. Believe me, that’s not a flavor you want in your keto lemon bars.
  • If you can’t find Confectioners’ Swerve or powdered erythritol, you can make your own from granulated! Just run your granulated Swerve/erythritol through a food processor, pulsing until it’s a powdery consistency. Start with about half the total amount called for in the recipe (so here you’d start with 2 tablespoons granulated Swerve) since it’ll expand as it becomes powdery. Measure after pulsing and add more as needed!
  • Don’t over-bake the lemon bars. They’ll keep cooking a little while they rest in the baking dish, and the lemon filling will thicken more while it chills in the fridge.
  • If you’re serving these keto lemon bars at a party or event, or you just want them to look extra nice, then how you cut them matters! For the cleanest edges, use a serrated knife that’s been warmed under hot water and make sure the lemon bars are completely chilled. Wipe any lemon filling off the knife between each cut, too. That way you’re not dragging excess filling across the next bars you cut.
Close up of one keto lemon surrounded by keto lemon bars

🍰 Other Keto Sweet Treats You’ll Love

Recipe By: Cheryl Malik

Keto Lemon Bars

Prep 10 minutes
Cook 45 minutes
Cool 30 minutes
Total 1 hour 25 minutes
Classic lemon bars made keto! Perfectly tart and sweet, this keto dessert is quick and easy to prepare and guaranteed to satisfy any sweet tooth. One of my family's favorite keto treats.
12 bars


  • Oven
  • 8×8 baking dish
  • parchment paper
  • 2 Large bowls
  • Fork
  • wire cooling rack
  • whisk
  • Sifter or fine mesh sieve


For the Shortbread Crust

  • 6 tablespoons unsalted butter melted but not bubbling
  • 2 ½ cups super-fine blanched almond flour
  • ¼ cup Confectioners' Swerve see Notes
  • 1 pinch salt
  • 1 teaspoon finely grated lemon zest

For the Lemon Filling

  • 4 large eggs at room temperature
  • cup fresh lemon juice juice from approximately 5 lemons
  • ¼ cup super-fine blanched almond flour
  • cup Confectioners' Swerve

Suggested Toppings (All Optional)

  • Confectioners' Swerve
  • thinly-sliced lemon quarters


For the Shortbread Crust

  • Preheat oven to 350° Fahrenheit. Line 8×8 baking dish with parchment paper, leaving just enough parchment paper hanging out sides of dish to use as handles later. Set baking dish aside.
  • Add melted butter, almond flour, Swerve, salt, and lemon zest to large mixing bowl. Mix well until ingredients are thoroughly combined to form shortbread dough.
    Lemon bar crust dough in a large glass mixing bowl
  • Transfer dough to prepared baking dish. Press dough across bottom of dish in one even layer, making sure dough reaches into all 4 corners of dish.
    Lemon bar crust in a baking dish
  • Place baking dish in preheated oven. Bake 15 to 20 minutes, or until crust is just golden.
  • Once desired color is achieved, carefully remove baking dish from oven and set aside to cool on wire cooling rack 5 to 10 minutes.

For the Lemon Filling

  • Crack eggs directly into large mixing bowl, then add lemon juice, almond flour, and Swerve. Whisk ingredients together vigorously until mixture is well combined and thick.
  • Pour lemon filling directly onto pre-baked crust, smoothing filling out into one even layer and into corners of dish.
  • Return baking dish to oven. Bake 20 minutes or until filling is fully set but still soft and slightly jiggly. Be careful not to overbake.
    Keto lemon bars in a square baking dish
  • Carefully remove baking dish from oven and return to wire cooling rack. Allow dish to cool to room temperature, at least 30 minutes.
  • Once lemon bar mixture has cooled completely, place baking dish in refrigerator until completely chilled.

To Serve

  • Remove baking dish from refrigerator. Use edges of parchment paper to lift large lemon bar sheet out of baking dish and transfer to flat surface.
  • Use sharp, warmed knife to cut large lemon bar sheet into 9, 12, or 16 lemon bars, depending on preferred portion sizes.
  • If desired, lightly sprinkle Confectioners' Swerve over top of lemon bars using sifter or fine mesh sieve. Garnish each bar with thinly-sliced lemon quarters and serve immediately. Alternately, place prepared lemon bars in airtight container and refrigerate until ready to serve.


  • Confectioners’ Swerve: Powdered erythritol will work in its place, but you may need to use more of it to match the sweetness. For powdered erythritol, try cup in the crust and ¾ cup in the filling.
  • Dusting: Don’t overdo the Swerve or erythritol at the end. Too much will have a cooling effect that throws off the overall taste of the bars, so keep it light.
  • Make it Dairy Free: Use vegan butter. 
  • Make it Vegan: Use vegan butter and follow this recipe for vegan lemon curd.

Approximate Information for One Serving

Serving Size: 1 keto lemon barCalories: 221calProtein: 7gFat: 18gSaturated Fat: 4gTrans Fat: 0.2gCholesterol: 70mgSodium: 69mgPotassium: 229mgTotal Carbs: 18gFiber: 12gSugar: 2gErythritol: 4gNet Carbs: 2gVitamin A: 255IUVitamin C: 5mgCalcium: 77mgIron: 2mg
Nutrition Disclaimers
Number of total servings shown is approximate. Actual number of servings will depend on your preferred portion sizes.
Nutritional values shown are general guidelines and reflect information for 1 serving using the ingredients listed, not including any optional ingredients. Actual macros may vary slightly depending on specific brands and types of ingredients used.
To determine the weight of one serving, prepare the recipe as instructed. Weigh the finished recipe, then divide the weight of the finished recipe (not including the weight of the container the food is in) by the desired number of servings. Result will be the weight of one serving.

Did You Make This Recipe?

Tag @40aprons on Instagram and be sure to leave a review on the blog post!

Leave A Review

Your email address will not be published. Required fields are marked *

Recipe Rating

This site uses Akismet to reduce spam. Learn how your comment data is processed.


  1. I was never able to get the lemon topping ‘thick’ after a lot of whisking and then even trying to use my hand mixer. It was still liquid. Finally I added 4 tsp cornstarch and it still did not thicken. In a last ditch effort, I poured the liquid mix into a pie pan and baked it and it came out fine and later I spread it over the crust. I doubled checked the recipe and it appears I followed the instructions. End result was tasty. I would not try it again.

    1. Avatar Jessica | 40 Aprons Team says:

      Hi Martha! So sorry to hear this didn’t turn out as expected. I’d love to troubleshoot it with you- did you pour the filling into your crust-lined baking dish and bake for 20 minutes?

  2. Can you use Granulated Swerve?

    1. Megan | 40 Aprons Team Megan | 40 Aprons Team says:

      Hi, Claire! You can, but the granulated might give you a kind of gritty texture. The Confectioners’ Swerve is much smoother and blends better!

      You can always turn your granular Swerve into Confectioners’, like we mention in the Chef’s Tips section! Just give the granulated Swerve a few pulses in a food processor (or even a coffee grinder or high speed blender) until you’ve got a powdery consistency.

  3. These look so yummy! But isn’t 4 eggs a lot – I’m worried they’ll taste really eggy?

    1. Avatar Savannah | 40 Aprons Team says:

      We don’t think these tasty super eggy!

Where To Next?