How long does it take to cook boiled potatoes?

Approximately 10 to 25 minutes at a high boil. The time required to boil potatoes depends on whether and how the potatoes are cut up. Smaller pieces, such as cubes, expose more surface area to the boiling water and so cook more quickly than larger pieces. Whole potatoes will take the longest time to boil until done.

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Boil them long enough that a fork will enter them without much effort.