owner's 401(k) deposits<>contribution - amend or late deposit

Small plan, 20 ee's.

Just discovered that expected accrued deposit of 401(k) (for owners only) at beginning of prior yr do not match their 5500 as well as personal and company taxes.

contemplating 2 options:

• Amend all taxes and 5500 to match actual deposit
• Deposit the 401(k) amount (~5000 in total), over a year later

Do the owners have earned income (LLC/parternship) or are they W-2 employees (corporation)?

If it is a corporation, find their pay stubs and confirm if the amounts were actually withheld from their pay. If they were withheld, deposit the amounts now, with lost earnings, and pay the excise tax. If they were not withheld, amend the returns.

If it is a partnership/LLC, so there are no W-2s to refer to, then you have to look at the partners' elections (the partners do make a written deferral election before the end of the year, right?). Then, same logic as before. If they elected to defer the amount but it was never deposited, deposit it now; if they did not elect to defer that amount, then amend the returns.

W-2. It appears their W-2 indicates amounts were withheld from pay. Thanks!

Okay, so we are nearly 18 months after end of plan year. Gotta figure out which 5330 Schedule.