The September 15 Checklist

Extended Forms 1065 and 1120-S are due Tuesday, September 15. These are the eight things we reconcile before we file one.

Your readiness

0 of 8

Tick each item you can confirm today.

Bank, credit card and loan accounts reconciled through year-end Every account, not just the main operating one.

Prior-year return on hand, and opening balances agree to it If the books don't start where last year's return ended, everything after it is off.

Capital accounts roll forward and tie to last year's K-1s Contributions, distributions, and the share of income each owner was allocated.

Basis tracked for every owner receiving a K-1 Owners need it to know whether their loss is deductible. It is their number, but it comes from your books.

Owner loans have written terms and agree on both sides A balance the entity shows as payable should match what the owner shows as receivable.

Intercompany balances agree entity to entity and net to zero If you run more than one entity, this is where most late-filing surprises come from.

Officer compensation on payroll, guaranteed payments recorded S-corp owners taking distributions without reasonable wages is the most commonly examined item on the return.

Fixed asset additions, disposals and depreciation method confirmed Anything bought, sold or written off during the year, and the method behind it.

What missing it costs

The failure-to-file penalty on a 1065 or 1120-S is charged per owner, per month — whether or not the entity earned a dollar, and whether or not any tax is owed.

Returns still open Entities that haven't filed yet

Total K-1s across those returns Count every partner and shareholder

Penalty per owner, per month Indexed annually — confirm the figure for the year your return is due

How late A partial month counts as a full month

Penalty at the lateness you selected Per-owner monthly figure, multiplied by every K-1 and by each month or part month late.

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If it runs the full 12 months The penalty stops accruing after 12 months. Interest on what the owners themselves owe does not.

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Estimate only. Built entirely on the figures you enter. The per-owner monthly penalty is adjusted for inflation each year, so confirm the amount that applies to the year your return is due. This is not tax advice — talk to your CPA.