Key Lime Bars Recipe

Our Key Lime Pie Bars have become a trusted favorite whenever we want a dessert that’s easy, vibrant, and bursting with flavor. Featuring a rich, buttery graham cracker crust and a zesty lime filling, these bars come together simply but feel special enough for any occasion.

We’ve made this recipe countless times because it never lets us down. The filling is silky and luscious, perfectly balanced with citrus zing, and when chilled, these bars cut cleanly for a lovely presentation. This dessert is our go‑to each summer, and it somehow always disappears in no time.

Why we think you’ll love it:

• A burst of refreshing citrus. The tart lime filling keeps these bars light and perfect for warmer days or when you want a dessert that’s not too heavy after dinner.
• Super easy to whip up. With only 10 simple ingredients and straightforward steps, these bars come together quickly. Aside from chilling time, they take about 30 minutes from start to finish!
• Perfect for sharing. The square pan creates neat, uniform bars that are great for potlucks or any get‑togethers.
• Pre-make friendly. These bars chill in the fridge, making them ideal to prepare in advance before guests arrive.

Read MoreRead Less

These Key Lime Pie Bars are my go-to dessert when I want something bright, simple, and that everyone will enjoy. They feature a buttery graham cracker base topped with a tangy, creamy lime filling that chills into perfect slices — light, refreshing, and just right as a finish to a meal or for summer parties.

As you read through this post, I’ll guide you step-by-step through making them, from a short and sweet ingredient list (just 10 common ingredients) to clear instructions with photos. I’ll also share timing tips (about 30 minutes of prep and baking plus 2–4 hours chilling), tricks for getting that picture-perfect texture and slices, plus ideas for crust options, toppings, storage, and answers to your most asked questions. You’ll be confident making these bars again and again.

Why You’ll Love These Bars

• Bright, fresh citrusy flavor that feels just right on warmer days or after heavier meals — and if you’re craving more citrus, try Lemon Blueberry Delight.
• Simple and dependable — pantry staples and a no-fuss method mean you get consistent, delicious results every single time.
• Prep ahead with ease — the bars need chilling, so you can make them before your event. For another chilled, make-ahead dessert, see No Bake Strawberry Cheesecake.
• Pretty, easy-to-serve slices — the 9×9 pan gives you tidy, crowd-friendly bars.
• Lots of tasty topping ideas — try whipped cream, toasted coconut, lime slices, or fresh lime zest to dress them up.

Ingredients and Swaps

• Graham crackers (15 sheets) — crushed, about 1¾ cups of crumbs
• Sugar (2 tablespoons)
• Salt (just a pinch)
• Unsalted butter, melted (6 tablespoons)
• Cream cheese, softened (6 ounces)
• Sweetened condensed milk (1 (14-ounce) can)
• Egg yolks (4)
• Lime zest (1 tablespoon)
• Key lime juice or regular lime juice (½ cup) — for key lime juice, mix 3 tablespoons lime juice with 1 tablespoon lemon juice if needed
• Vanilla extract (½ teaspoon)

Make the Bars

1. Preheat oven to 350°F and line a 9×9-inch square pan with parchment or foil, leaving an overhang for lifting.
2. Zest limes before juicing.
3. Crush 15 graham cracker sheets into fine crumbs (about 1¾ cups).

4. Mix graham cracker crumbs with 2 tablespoons sugar, a pinch of salt, and 6 tablespoons melted butter.

   

5. Press the crumb mixture firmly and evenly into the bottom of the prepared pan to form a compact crust.
6. Bake the crust for 10 minutes.
7. Bring 6 ounces cream cheese to room temperature.

8. Beat the softened cream cheese until completely smooth.

   

9. Gradually add a 14-ounce can sweetened condensed milk and mix until silky.
10. Add 4 egg yolks one at a time, blending well after each addition.
11. Stir in 1 tablespoon lime zest, ½ cup lime juice, and ½ teaspoon vanilla until fully combined.

12. Pour the filling over the warm crust and smooth the top.

    

13. Bake for 15–18 minutes, until the filling is set, the surface remains pale, and the center is slightly jiggly.
14. Cool the bars completely at room temperature.
15. Chill the bars in the refrigerator for at least 2–4 hours.

16. Use the parchment overhang to lift the bars from the pan.

    

17. For clean slices, run a sharp knife under hot water, dry it, and slice, wiping the blade between each cut.

    

Pro Tips for Perfect Bars

• Use room temperature cream cheese so the filling blends perfectly smooth with no lumps.
• Press your graham cracker crust mixture firmly and evenly into the pan to make sure it sticks together well when sliced.
• Avoid overbaking the filling — pull it from the oven when it’s just set but still a bit soft in the center. It will finish firming up in the fridge.
• Zest your limes before juicing them to get the best citrus fragrance and avoid adding any bitter pith.
• For nice clean slices, chill the bars fully (at least 2–4 hours or overnight). Run a sharp knife under hot water, dry it, then slice, wiping the blade between each cut — the same warm-knife trick works beautifully for serving the Easy Strawberry Crunch Ice Cream Cake.
• If you use salted butter in the crust, skip the extra pinch of salt in the crumbs so the crust doesn’t become too salty.

Flavor and Crust Swaps

• Crust swaps: Try vanilla wafers, shortbread cookies, or gluten-free graham crackers instead of classic grahams, all adding their own twist.
• Toppings: Add whipped cream, lime slices, toasted coconut, or sprinkle extra lime zest on top before serving for a fun presentation.
• Mini bars: Bake in a lined muffin tin for easy single servings. Adjust baking time; keep an eye for a set center.
• Flavor twists: Stir in a few tablespoons of lime curd or swirl in some raspberry puree before baking for a pretty, tasty upgrade.
• Dairy notes: You can swap reduced-fat cream cheese for regular, but expect a slightly firmer, less rich filling.

Storage and Make-Ahead

• Refrigerate: Keep leftover bars covered or stored tightly in an airtight container in the fridge for up to 4–5 days.
• Freeze: Wrap individual bars tightly in plastic wrap and freeze in a sealed bag or container for up to 1 month. Thaw overnight in the fridge before serving.
• Make-ahead: These bars are easy to bake in advance. Bake and chill overnight, making slicing and serving a breeze the next day.
• Serving: Bars are best chilled, but if they’re a bit too firm from the fridge, let them sit at room temperature for 10–15 minutes before cutting to soften slightly.

Questions and Troubleshooting

• Can I use regular limes instead of key limes? Absolutely! Regular (Persian) limes work beautifully and are a common, tasty substitute for key limes.
• What if I don’t have sweetened condensed milk? Sweetened condensed milk adds sweetness and body to the filling, so substituting it will change the texture and flavor. If needed, you might try adjusting sugar and making a thickened milk reduction, but keep in mind results will vary.
• Can I use whole eggs instead of yolks? Using whole eggs will result in a firmer, less creamy filling. The recipe is designed for yolks to keep things smooth and rich.
• How do I avoid cracks on top? The key is not to overbake and to keep the top from browning. Bake until set but still slightly soft, then cool and chill slowly to prevent cracking.
• Can I make these gluten-free? Yes! Simply swap the crust for gluten-free graham crackers or another gluten-free cookie to keep these bars gluten-free.