This key lime mojito is bright, minty, and full of fresh citrus flavor. White rum, key lime juice, and a splash of simple syrup come together over ice, with bubbly club soda to finish. It’s an easy cocktail for a patio afternoon, taco night, or a summer gathering.

If you love a classic mojito but want to change up the citrus, this version keeps the familiar mint-and-rum combination and swaps in key lime juice. No blender, cocktail shaker, or complicated prep required.

Key Lime Mojito

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Prep Time 5

Servings: 1

Ingredients Method Notes

Ingredients

8 –10 fresh mint leaves plus a sprig for garnish
1 ounce key lime juice freshly squeezed if available
¾ ounce simple syrup plus more to taste
2 ounces white rum
Ice enough to fill a tall glass
2 –3 ounces chilled club soda to top
Key lime wheel or wedge for garnish

Method

Gently muddle the mint
Add the mint leaves and simple syrup to a tall glass. Press gently with a muddler a few times, just until the mint smells fragrant. You want to release its aroma without shredding the leaves.
Add the key lime juice and rum
Pour in the key lime juice and white rum. Stir to combine.
Fill the glass with ice
Add plenty of ice. Ice cubes melt more slowly than finely crushed ice, while crushed ice gives the drink a frosty finish.
Top with club soda
Add 2–3 ounces of chilled club soda, depending on the size of your glass. Give the drink one gentle stir.
Garnish and serve
Lightly clap a mint sprig between your palms to release its aroma, then tuck it into the glass. Add a key lime wheel or wedge and serve immediately.
Taste before serving. If the drink is sharper than you like, stir in another teaspoon of simple syrup.

Notes

Key lime juice: Measure the juice rather than relying on a set number of limes, since their size and juiciness vary. Bottled key lime juice works too; choose unsweetened juice rather than a sweetened lime mixer.
Fresh mint: Use the leaves in the drink and save a leafy sprig for garnish. Avoid muddling thick stems.
White rum: Its relatively light flavor lets the lime and mint shine. A rum you already enjoy in mojitos is a good choice.
Simple syrup: This mixes into a cold cocktail more easily than granulated sugar. The recipe uses a syrup made with equal parts sugar and water.
Club soda: Use plain, unflavored club soda or sparkling water. Sweetened lemon-lime soda will change the sweetness and flavor.

Easy Variations

Coconut Key Lime Mojito

Replace 1 ounce of the white rum with 1 ounce of coconut rum. Start with ½ ounce simple syrup, then taste and adjust, since coconut rum may add sweetness.

Strawberry Key Lime Mojito

Muddle two hulled, sliced strawberries with the syrup before adding the mint. Gently press the mint, then continue with the recipe.

Spicy Key Lime Mojito

Muddle one thin jalapeño slice with the syrup before adding the mint. Remove the pepper slice before finishing the cocktail if you prefer less heat.

Key Lime Mojito Mocktail

Omit the rum and add extra club soda to taste. Start with ½ ounce simple syrup and adjust after adding the lime juice and soda.

Make Key Lime Mojitos for a Group

For 6 cocktails, use:

48–60 mint leaves, divided among the glasses
6 ounces key lime juice
4½ ounces simple syrup
12 ounces white rum
12–18 ounces club soda
Ice and garnishes

Combine the key lime juice, simple syrup, and rum in a pitcher and refrigerate until serving.

For each drink, gently press 8–10 mint leaves in a glass, add 3¾ ounces of the prepared mixture, and fill with ice. Top with 2–3 ounces of club soda and garnish.

Keep the soda and ice separate until serving so the drinks stay fizzy and don’t become diluted.

What to Serve with Key Lime Mojitos

Pair these mojitos with fish tacos, chips and guacamole, grilled shrimp skewers, or mango salsa. For a casual summer spread, add a bowl of tortilla chips and a platter of fresh pineapple.

Frequently Asked Questions

Can I use regular limes instead of key limes?

Yes. Use the same amount of regular lime juice. The flavor will be a little different, but it still makes a delicious mojito.

Can I use bottled key lime juice?

Yes. Use unsweetened bottled key lime juice and taste the drink before adding extra syrup. Avoid substituting sweetened lime cordial in the same quantity.

Do I need a muddler?

No. The end of a clean wooden spoon works. Press gently, and use a sturdy glass.

Can I make it ahead?

You can mix the rum, key lime juice, and syrup ahead and refrigerate the mixture. Add the mint, ice, and club soda when serving.

Does this taste like key lime pie?

This is a citrus-and-mint cocktail with a crisp, bubbly finish. It doesn’t contain cream, condensed milk, or graham crackers, so it won’t have the creamy flavor of key lime pie.

Key Lime Mojito Recipe