Hello and welcome to Just Answer.
Is this a commercial or residential installation? Do you have parallel lugs for the load side of the meter socket?
Do you plan to use copper or aluminum wire?
4/0 aluminum is OK for residential. Will the panels be mounted next to each other and where will they be mounted in the house? Do you plan on running service entrance cable or do you want to run 3 individual conductors in conduit from the meter to the panels?
I see you have this question posted 2 times here. We must close one of these questions. Electric Doctor answered you in the other question first.