[Question] How many steam account per phone number?

1

i am assuming for steam guard? if so, multiple...

read here: https://support.steampowered.com/kb_article.php?ref=8625-wrah-9030#morethanone

There are public phone numbers used at hundreds of accounts at the same time. Some people even posted a few videos about getting themselves VAC banned deliberately so all accounts would suffer the same.

IIRC limit is around 100, maybe more, with limit of 5 account activations daily.