Begin by assembling all necessary ingredients.
In a pitcher or a large liquid measuring cup with a pour spout, combine the lime juice with the simple syrup. Stir thoroughly until the mixture is well blended.
Fill four tall glasses generously with ice cubes to keep the drink crisp and refreshing.
Pour approximately 3 ounces of the lime-syrup blend into each glass.
Top off each serving with an equal amount of seltzer water—around 3 ounces per glass—allowing the effervescence to lift the citrusy aroma.
Using a swizzle stick or a long-handled spoon, gently stir each glass to blend the flavors evenly.
Add a fresh lime wedge or two to the rim or directly into the drink as a vibrant garnish. Serve immediately.