Hi, client has W2 income where he contributed $14K pre-tax and about $50K schedule C income. When I check the max to contribute to solo 401K in Proseries Basic it says $31K. It seems like 1. it's not accounting for the $14K contribution on the W2 income and also the fact that it's past 4/15. If I'm not mistaken, he can contribute employer portion only past the 4/15 deadline which is around $9K?

This is the first year, the account is not yet established. Does the extension allow for retroactive employer contributions?

Thank you!