This Sugar Free Key Lime Pie Recipe is everything you want from the classic Florida dessert, minus the sugar crash afterward.
A buttery graham cracker crust holds a tangy, creamy lime custard that sets up firm enough to slice clean but still melts on your tongue.
I make this one all summer long because it takes about twenty minutes of hands-on work and the oven does the rest.
| Quick Recipe Summary | |
|---|---|
| Prep Time | 20 minutes |
| Cook Time | 15 minutes |
| Chill Time | 4 hours |
| Total Time | 4 hours 35 minutes |
| Servings | 10 slices |
| Difficulty Level | Easy |
Why You’ll Love This Sugar Free Key Lime Pie Recipe
This pie proves that cutting sugar doesn’t mean cutting flavor.
The filling still gets that unmistakable tart, sweet, silky balance that key lime pie is famous for.
It also happens to be one of the easier make-ahead desserts in my rotation, since it genuinely tastes better the next day.
If you like tangy, chilled desserts, my Lemon Icebox Pie Recipe is another one worth bookmarking.
- Uses sugar substitutes instead of refined sugar in both the crust and filling
- Only 15 minutes of bake time, most of the work happens in the fridge
- Bright, tart lime flavor that never tastes artificial
- Great make-ahead dessert for dinner parties, potlucks, or holiday tables
- Naturally lower in carbs than a traditional key lime pie
- Simple ingredient swaps mean no specialty baking skills required
Ingredients
You’ll need a short list of pantry staples plus a few sugar-free swaps to pull this recipe together.
Fresh key limes make the biggest difference in flavor, but bottled key lime juice works in a pinch.
- For the Crust: 1 and 1/2 cups sugar-free graham cracker crumbs, 6 tablespoons unsalted butter (melted), 3 tablespoons granulated monk fruit sweetener, a pinch of salt
- For the Filling: 4 large egg yolks, 4 ounces cream cheese (softened), 1 can (14 ounces) sugar-free sweetened condensed milk, 1/2 cup fresh key lime juice or bottled key lime juice, 1 tablespoon key lime zest, 1/4 cup powdered monk fruit sweetener
- For the Topping: 1 cup heavy whipping cream, 2 tablespoons powdered monk fruit sweetener, 1 teaspoon vanilla extract, extra lime zest and thin lime slices for garnish
Kitchen Equipment Needed
Nothing fancy here, just a few basics that make the process smoother.
A stand mixer isn’t required, but a hand mixer will save your arm during the whipped topping step.
Read Also: No Bake Cheesecake Recipe
- 9-inch glass pie dish
- Mixing bowls (a few sizes)
- Hand mixer or stand mixer
- Microplane zester
- Citrus juicer
- Rubber spatula
- Wire cooling rack
Recommended Products for This Recipe
These are the products I personally reach for every time I make this pie, based on years of testing different brands and tools in my own kitchen.
None of these are required, but they’ll make the process faster and the results more consistent.
I use the same crumb crust method in my Lemon Cheesecake Recipe, so this equipment gets a lot of use around here.
1. Lakanto Monk Fruit Sweetener
This is the sweetener I default to for both the crust and filling because it measures cup for cup like sugar and doesn’t leave a cooling aftertaste.
It dissolves cleanly into the filling instead of turning gritty once the pie chills.
A bag of this lasts through several batches, so it’s worth having on hand.
2. Nellie & Joe’s Key West Lime Juice
When fresh key limes aren’t in season, this bottled juice is the closest thing to the real deal. It has that sharp, floral tartness that regular limes just don’t replicate as well.
I keep a bottle in my fridge year round for this exact recipe.
3. Pyrex 9 Inch Glass Pie Plate
A glass pie plate heats evenly, which matters when you’re trying to avoid overbaking a custard filling.
It also lets you check the crust color as it bakes without having to guess. This one has survived years of regular use in my kitchen.
4. OXO Good Grips Zester
Good lime zest makes a real difference in this recipe, and a sharp, comfortable zester makes that step painless.
It grabs just the fragrant outer peel without any of the bitter white pith underneath.
I reach for this same tool anytime a recipe calls for citrus zest.
Step-by-Step Instructions: How to Make Sugar Free Key Lime Pie
1. Preheat the Oven and Prepare the Crust
- Preheat your oven to 325°F (163°C) and set a rack in the middle position.
- In a mixing bowl, combine the sugar-free graham cracker crumbs, melted butter, granulated monk fruit sweetener, and a pinch of salt.
- Stir with a fork until every crumb is evenly coated and the mixture looks like wet sand.
- Press the mixture firmly into the bottom and up the sides of your 9-inch glass pie dish, using the bottom of a measuring cup to pack it down evenly.
2. Bake the Crust
- Place the pie dish on the middle oven rack and bake the crust for 8 to 10 minutes, until it looks set and just barely golden at the edges.
- Remove the crust from the oven and set it on a wire cooling rack.
- Let the crust cool for about 10 minutes while you prepare the filling. Leave the oven on at 325°F.
3. Whisk the Egg Yolks
- In a large mixing bowl, whisk the 4 egg yolks by hand for about 1 minute, until they look slightly pale and thickened.
- This step helps the filling set into a smooth, sliceable custard once baked.
4. Beat in the Cream Cheese and Condensed Milk
- Add the softened cream cheese to the egg yolks and beat with a hand mixer on medium speed until fully smooth, with no lumps remaining.
- Slowly pour in the sugar-free sweetened condensed milk while continuing to mix on low speed.
- Beat until the mixture is fully combined and silky, scraping down the sides of the bowl as needed.
5. Add the Lime Juice, Zest, and Sweetener
- Add the key lime juice, key lime zest, and powdered monk fruit sweetener to the filling.
- Mix on low speed just until combined. The mixture will thicken slightly as the acid from the lime juice reacts with the dairy, which is exactly what you want.
- Taste the filling here and adjust sweetness if needed, since sugar substitutes can vary in intensity between brands.
6. Bake the Pie
- Pour the filling into the cooled crust and smooth the top with a spatula.
- Bake at 325°F for 15 minutes, until the edges look set but the center still has a slight jiggle when you nudge the dish.
- Do not overbake, since the filling will continue to firm up as it cools.
7. Cool and Chill the Pie
- Remove the pie from the oven and set it on the wire cooling rack to cool completely at room temperature, about 1 hour.
- Once cooled, cover the pie loosely and refrigerate for at least 4 hours, or overnight, until fully chilled and set.
8. Make the Whipped Topping and Garnish
- Just before serving, add the heavy whipping cream, 2 tablespoons powdered monk fruit sweetener, and vanilla extract to a chilled mixing bowl.
- Beat with a hand mixer on high speed until stiff peaks form, about 2 to 3 minutes.
- Spread or pipe the whipped cream over the chilled pie, then finish with extra lime zest and thin lime slices before slicing and serving.
Tips for The Best Sugar Free Key Lime Pie
A few small details separate a good key lime pie from a great one.
Most of them come down to temperature control and taste-testing as you go.
For more sugar-conscious dessert inspiration, my Sugar Free Pecan Pie Recipe follows a lot of the same principles.
- Use room temperature cream cheese so it blends smoothly without lumps
- Zest your limes before juicing them, it’s much easier that way
- Don’t skip the cooling step before chilling, or condensation can make the crust soggy
- Taste the filling before baking and adjust sweetener to your preference
- Chill the pie for the full 4 hours for the cleanest slices
- Use a sharp knife dipped in warm water for neater cuts
Serving Suggestions
This pie is rich and tangy, so it pairs best with something light on the side.
A small scoop of fresh berries or a simple herbal iced tea rounds out the meal nicely.
If you’re planning a full spread, this pie also fits right in next to Lemon Cheesecake on a dessert table.
- A dollop of extra sugar-free whipped cream
- Fresh berries like raspberries or blackberries on the side
- A thin slice of extra lime for garnish
- Sparkling water with a splash of lime
- Iced herbal tea, such as hibiscus or mint
Variations of Sugar Free Key Lime Pie
Once you’ve made the base recipe once, it’s easy to customize.
Here are a few swaps I’ve tried and liked over the years.
You might also enjoy: Sugar Free Pumpkin Pie Recipe
- Nut Crust Version: Swap the graham cracker crust for a crushed almond and butter crust for a lower-carb option
- Coconut Lime Pie: Fold 1/4 cup shredded unsweetened coconut into the filling before baking
- Mini Pies: Divide the crust and filling among a muffin tin for individual portions, reducing bake time to about 10 minutes
- Extra Tart Version: Increase the lime juice to 2/3 cup for a more pucker-worthy filling
- Dairy-Free Version: Use dairy-free cream cheese and coconut cream in place of the whipped topping
Storage and Reheating
This pie is a fridge dessert through and through, so no reheating is involved.
Proper storage just means keeping it cold and covered.
My No Bake Cheesecake Recipe follows nearly identical storage rules if you want to compare notes.
- Cover the pie tightly with plastic wrap or store in an airtight container
- Refrigerate for up to 4 days
- Add whipped topping just before serving if storing for more than a day
- Freeze the baked pie (without whipped topping) for up to 1 month, wrapped tightly
- Thaw frozen pie overnight in the refrigerator before topping and serving
Nutritional Facts
Below is an approximate breakdown per slice, based on 10 slices per pie.
Actual values will vary depending on the specific sugar-free products you use.
For another lighter dessert breakdown, see my Sugar Free Sweet Potato Pie Recipe.
| Nutritional Facts (Per Slice) | |
|---|---|
| Calories | 270 |
| Total Fat | 21g |
| Saturated Fat | 12g |
| Cholesterol | 135mg |
| Sodium | 190mg |
| Total Carbohydrates | 11g |
| Fiber | 1g |
| Sugar Alcohols | 6g |
| Protein | 6g |
Health Benefits of Key Ingredients
Beyond being lower in sugar, a few ingredients in this pie bring their own nutritional perks.
It’s still a dessert, but it’s nice to know what’s actually in your slice.
My Lemon Cheesecake Bars Recipe shares several of these same ingredients.
- Key Limes: High in vitamin C and antioxidants that support immune health
- Eggs: A good source of protein and choline, which supports brain function
- Cream Cheese: Provides calcium and a small amount of protein
- Monk Fruit Sweetener: A zero-calorie sweetener that doesn’t spike blood sugar the way refined sugar does
- Heavy Cream: Contains fat-soluble vitamins A and D
FAQs About Sugar Free Key Lime Pie
1. Can I use regular limes instead of key limes?
Yes, regular Persian limes work fine if key limes aren’t available.
You’ll need slightly fewer of them since they’re larger, but the flavor will be a touch less tart and floral than true key limes.
2. Is this pie keto friendly?
It can be, depending on which sugar-free products you choose.
Check the labels on your sweetened condensed milk and graham cracker crumbs, since some brands add more net carbs than others.
3. Can I make this pie ahead of time?
Absolutely, and it actually tastes better after chilling overnight. Just hold off on adding the whipped topping until closer to serving time.
4. Why is my filling not setting properly?
This usually means the pie needed a few more minutes in the oven or didn’t chill long enough.
The filling firms up significantly during the 4-hour chill, so resist the urge to slice it early.
5. Can I freeze sugar free key lime pie?
Yes, the baked filling freezes well for up to a month if wrapped tightly.
Add the whipped topping and garnish only after it’s fully thawed in the fridge.
Sugar Free Key Lime Pie
Ingredients
- 1 1/2 cups sugar-free graham cracker crumbs
- 6 tablespoons unsalted butter melted
- 3 tablespoons granulated monk fruit sweetener
- salt a pinch
- 4 large egg yolks
- 4 ounces cream cheese 113g, softened
- 1 can sugar-free sweetened condensed milk 14 oz or 396g
- 1/2 cup key lime juice fresh or bottled
- 1 tablespoon key lime zest
- 1/4 cup powdered monk fruit sweetener
- 1 cup heavy whipping cream 240ml
- 2 tablespoons powdered monk fruit sweetener
- 1 teaspoon vanilla extract
- lime zest extra for garnish
- lime slices thin slices for garnish
Equipment
- 9-inch glass pie dish
- Mixing bowls several sizes
- Hand mixer or stand mixer
- Citrus juicer
- Rubber spatula
- Wire cooling rack
Method
- Preheat oven to 325°F (163°C). In a mixing bowl, combine graham cracker crumbs, melted butter, granulated monk fruit sweetener, and a pinch of salt. Stir until every crumb is evenly coated. Press mixture firmly into the bottom and up the sides of your 9-inch glass pie dish.
- Bake crust for 8 to 10 minutes until set and lightly golden at the edges. Remove from oven and cool for about 10 minutes while you prepare the filling. Leave the oven on at 325°F.
- In a large mixing bowl, whisk the egg yolks by hand for about 1 minute until slightly pale and thickened. Add softened cream cheese and beat with a hand mixer on medium speed until completely smooth with no lumps.
- Slowly pour in the sugar-free sweetened condensed milk while mixing on low speed. Beat until fully combined and silky, scraping down the sides of the bowl as needed. Add key lime juice, key lime zest, and powdered monk fruit sweetener. Mix on low speed just until combined.
- Pour the filling into the cooled crust and smooth the top with a spatula. Bake at 325°F for 15 minutes, until edges look set but the center still has a slight jiggle when you nudge the dish. Do not overbake.
- Remove pie from oven and cool completely on a wire rack, about 1 hour. Once cooled, cover loosely and refrigerate for at least 4 hours, or overnight, until fully chilled and set.
- Just before serving, beat heavy whipping cream, 2 tablespoons powdered monk fruit sweetener, and vanilla extract in a chilled bowl until stiff peaks form. Spread or pipe over the chilled pie and garnish with extra lime zest and thin lime slices.
Nutrition
Notes
- Use room temperature cream cheese so it blends smoothly without lumps
- Zest your limes before juicing them, it’s much easier that way
- Don’t skip the cooling step before chilling, or condensation can make the crust soggy
- Taste the filling before baking and adjust sweetener to your preference
- Chill the pie for the full 4 hours for the cleanest slices
- Use a sharp knife dipped in warm water for neater cuts
- For a nut crust version, swap the graham cracker crust for crushed almonds and butter
- Add whipped topping just before serving if storing for more than a day
- This pie actually tastes better the next day, making it a great make-ahead dessert
- The filling firms up significantly during the 4-hour chill, so resist the urge to slice it early
Private Notes
Tried this recipe?
Let us know how it was!Conclusion
This sugar free key lime pie proves you don’t have to give up dessert just because you’re watching your sugar intake.
It’s tart, creamy, and just as satisfying as the original.
Give it a try this week, and let me know in the comments how it turned out for you.
If you make it, I’d love to see it, so feel free to share a photo here.
Recommended:
- Cheesecake Pie Recipe
- Lemon Bars Recipe
- Lemon Meringue Pie Recipe
- Banana Cream Pie Recipe
- Chocolate Pie Recipe
