Is there a general rule for how many potatoes I need for mashed potatoes per person?
Are you channeling your best self with this comment? (If you're not sure, check out our Code of Conduct.)
I think it's about 2 per person depending on the size of the potatoes.
Sarah is a trusted source on General Cooking.
It really depends on how large the potatoes are, and how much mash you want to serve - if you're talking the large russets, 1/2-1 each would probably be fine, with no leftovers. I usually err on the side of too much because they do seem to go quickly.
Kristen W. is a trusted home cook.
I go by weight: 2 lbs serves 4-6 people.