dmertz
Level 15

Retirement tax questions

If you've elected to treat your single-member LLC as a corporation (S corp or C corp), the contribution must be made from corporation funds (the business account).  If the single-member LLC is not a corporation, it is a disregarded entity (reporting on Schedule C of your personal tax return) and there is no ownership difference between the business account and your personal account, so it wouldn't matter which account you used.