cooktime Timer running

How long to boil potatoes

Boiling times by cut and by variety, from whole potatoes down to 2 cm cubes, plus the times for mash and for potato salad.

Which foodTap to open
Potatoes
Boiling times for whole potatoes, cubes, slices and baby potatoes, all from a cold water start, with the fork test that tells you when to stop..
10 to 30 min
Potatoes for mashed potatoes
Floury potatoes, the right chunk size and the simmer time that gives fluffy mash instead of glue, including the steam dry step most recipes skip..
13 to 25 min
Potatoes for potato salad
Waxy potatoes hold their shape in a salad and floury ones fall apart in the bowl.
11 to 20 min

Cut size decides the time far more than variety does. A 2 cm cube is done in roughly a third of the time a whole potato needs, whatever kind of potato it is.

Variety decides the texture instead. Floury potatoes fall apart, which is what you want for mash and what ruins a salad. Waxy potatoes hold their shape, which is the other way round.

Three things that matter more than the timer

Start in cold water

Dropping potatoes into boiling water cooks the outside long before the middle catches up, so you get a mushy edge around a hard centre. Starting cold lets the whole potato heat through together. This is the opposite of the rule for eggs, and it is the most common potato mistake.

The fork test beats the clock

A fork should slide into the centre with almost no resistance, and the potato should not cling to it when you lift it. Every time here is a starting point, because a potato stored cold for a month behaves differently from one dug last week.

Match the variety to the job

Floury potatoes like Russet, Maris Piper and King Edward break down and take on butter, which makes them right for mash and wrong for salad. Waxy potatoes like Charlotte, red and new potatoes stay in one piece.

Common questions

Cold water or boiling water?

Cold, and this is the opposite of the egg rule. A potato is dense and heat takes time to reach the middle. Starting in boiling water sets the outside long before the centre is done, so you drain a potato falling apart on the outside and still hard in the middle.

Do I salt the water?

Yes. Around 10 g per litre is a reasonable middle; published advice ranges from about 5 to 20. Unlike pasta, potatoes sit in the water long enough to season through rather than only on the surface.

Egg times come from the thermal-diffusion equation for a spherical egg published by Charles D. H. Williams (University of Exeter), calibrated so a large fridge-cold egg at sea level matches the times cooks actually use. Size, starting temperature and altitude then follow from the physics. Treat the result as a very good starting point, not a guarantee, because pans, hobs and eggs all vary.