Preheat oven to 425˚F (220˚C). Lightly grease or line a large baking sheet with parchment paper.
In a large bowl, combine the flour, sugar, baking powder, and salt.
Cut in the cold butter using a dough blender, two forks, or your fingers. The texture should become coarse with no pieces larger than a pea.
Mix in the chives until coated in the flour.
Make a well in the center of the buttery mixture and add 1 cup (240 milliliters) of the buttermilk.
Mix just until the dough comes together. If needed, slowly add the remaining 1/4 cup (60 milliliters) buttermilk. If the mixture is too wet, add a little more flour.
On a lightly floured surface, pat the dough into a sheet about 3/4 inch (2 centimeters) thick, flouring the top only as needed to keep it from sticking to your hands.
Use a 2 1/2 inch (6 centimeters) wide round cutter to cut out round biscuits, being careful not to twist the cutter as you press down.
Place the biscuits 1-2 inches (2.5-5 centimeters) apart on the prepared baking sheet. Gently press together the scraps and cut to form additional biscuits.
If desired, brush the tops with additional buttermilk.
Bake in preheated oven until flaky and bottoms are lightly golden brown, about 15 minutes.
Serve warm from the oven.