Bring the sugar, water, and sliced peaches to a boil in a small saucepan.
Reduce the heat. Stir with a wooden spoon while gently crushing the peaches to help release their flavor.
Once the sugar has dissolved, cover the saucepan, remove it from the heat, and let the peach syrup steep for 25-30 minutes.
Meanwhile, brew the black tea using the 8 cups of filtered water. Adjust the amount of tea depending on how strong you prefer it.
Steep the tea for no longer than about 4-5 minutes to prevent it from becoming bitter.
Remove the tea bags or strain out the loose leaf tea. Transfer the brewed tea to a pitcher and refrigerate until chilled.
Strain the finished peach simple syrup through a fine-mesh strainer into a bottle or container. The strained peaches can be reserved for another use.
To serve, add peach syrup to the chilled tea according to your preferred sweetness. Alternatively, stir all the syrup directly into the pitcher.
Serve the peach iced tea over ice with fresh peach slices.
