Place the sushi rice in a large bowl. Cover the rice with cold water. Use your hand to stir the rice in a circular motion. Drain the water. Repeat 3-4 times until the water remains clear.
Add the rinsed rice and 2 1/2 cups of water to a large pot. Let the rice soak for 30 minutes.
Bring the water to a boil, cover the pot, reduce the temperature to medium-low, and simmer for 10 minutes. DO NOT open the lid.
Turn off the heat and let the rice rest for another 10 minutes with the lid on.
Meanwhile, add the rice vinegar, sugar, and salt to a small saucepan. Cook over medium heat until the sugar and salt have dissolved.
Transfer the rice to a large bowl. Pour the vinegar mixture over the rice and fold carefully using cutting motions.
Cover the bowl with a damp towel and let the rice cool down. It's ready to use for sushi when the rice is at body temperature.