In a small saucepan, mix together frozen peaches, granulated sugar, and water. Place the saucepan over medium-low heat. Stir gently until the sugar begins to dissolve, about 3 to 5 minutes.

Raise the heat slightly to bring the mixture to a gentle simmer. Allow it to simmer for about 10 minutes, stirring occasionally until small bubbles form and the syrup starts thickening.

Once simmered, remove from heat and let cool for approximately 30 minutes to thicken and meld flavors.

Prepare a fine-mesh sieve over a glass bottle or jar and strain the peach mixture, pressing gently to extract as much liquid as possible.

Transfer the syrup into an airtight container. Store in the refrigerator for up to one week for sweetening drinks or desserts.