Gather all ingredients.
Place potatoes in a large pot and cover with cold salted water by about 1 inch. Bring to a boil.
Reduce heat to medium-low, cover and simmer until tender and easily pierced with a fork, 20 to 25 minutes.
Drain potatoes, then return to the pot. Turn heat to high and allow potatoes to dry for about 30 seconds. Turn off heat.
Mash potatoes with a potato masher twice around the pot, then mash in milk and butter until smooth and fluffy.
Season with salt and black pepper; whisk until evenly distributed, about 15 seconds.
