Key takeaways
- Check Final return in Item H on page 1 of Form 1120-S for a corporation that is dissolving.
- File Form 966 within 30 days after the owners adopt the resolution or plan to dissolve.
- A dissolved corporation generally files by the 15th day of the 3rd month after the dissolution date, not March 15.
- Asset-sale gains count toward Schedule B question 11 total receipts, so a liquidation year can fail the test on gains alone.
Check the Final return box
Page 1 of the 2025 Form 1120-S has an Item H with five check-if boxes: Final return, Name change, Address change, Amended return and S election termination. A corporation that is dissolving checks Final return. Do not carry the box forward from last year's return.
If the company keeps operating and only ends its S election, the return does not use the Final return box. The instructions say to attach to Form 1120-S for the final year of the S corporation a statement notifying the IRS of the termination and the date it occurred.
Decision rule: if the owners have voted to dissolve and will stop operating, check Final return. If the entity keeps operating as a corporation or another entity, handle the election change through the termination statement.
File Form 966 before the return
Form 966, Corporate Dissolution or Liquidation, is required under section 6043(a). A corporation must file it if it adopts a resolution or plan to dissolve the corporation or liquidate any of its stock. The form's instructions say to file it within 30 days after the resolution or plan is adopted.
Attach a certified copy of the resolution or plan and any amendments not previously filed. Line 4 asks for the date the resolution or plan was adopted. Line 10 asks for the Code section, and the form's example for a complete liquidation of a corporation is section 331.
Worked example: if the owners adopt the plan in early August, Form 966 is due in early September.
Do not file Form 966 for a deemed liquidation. The form's caution gives a section 338 election and an election to be treated as a disregarded entity as examples, so a tax-classification change alone does not trigger the form.
Count the due date from the dissolution date
For a calendar-year corporation that keeps operating, the Form 1120-S is due March 15. The instructions say a corporation that has dissolved must generally file by the 15th day of the 3rd month after the date it dissolved. That date replaces March 15 for the final return.
Worked example: a corporation that dissolves in August has its final return due on November 15. In 2026 November 15 falls on a Sunday. The instructions let the corporation file on the next day that is not a Saturday, Sunday or legal holiday, which is Monday, November 16, 2026.
Form 7004 gives an automatic 6-month extension. The instructions say the corporation generally must file Form 7004 by the regular due date of the return. Failure mode: a firm that calendars the final return from March 15 misses the deadline for a corporation that dissolved in the summer or early fall.
Apply the Schedule B question 11 test
On the 2025 form, question 11 asks whether total receipts for the year were less than $250,000 and whether total assets at the end of the year were less than $250,000. If both are true, the corporation does not complete Schedule L or Schedule M-1. Check the 2026 form when it is published.
Total receipts include more than cash sales. The instructions count gross receipts or sales on page 1, line 1a, all other income on page 1, lines 4 and 5, and income or net gain reported on Schedule K, lines 7, 8a, 9 and 10. A gain from selling business assets therefore counts.
Worked example: a corporation with $40,000 of sales and a $260,000 net section 1231 gain on Schedule K, line 9, has $300,000 of total receipts and fails the test. Complete Schedule L and Schedule M-1 from the final books. Decision rule: in any year with an asset sale, compute the total with the gain before answering question 11.
Report asset sales, distributed property and built-in gains
The instructions for Form 966 say a corporation must recognize gain or loss on the distribution of its assets in the complete liquidation of its stock, and distributed assets are valued at fair market value. Worked example: a building worth $300,000 with a tax basis of $120,000 that goes to the shareholders produces $180,000 of gain on the corporation's return.
Report each gain where its asset type puts it. Sales of business property go on Form 4797. The net ordinary gain or loss from Form 4797, Part II, line 17 reaches page 1, line 4 of Form 1120-S, and line 4 is part of the page 1 total on line 22 that Schedule K, line 1 reports. Net section 1231 gain does not go on page 1. It goes to Schedule K, line 9, with Form 4797 attached. Unrecaptured section 1250 gain goes on an attached statement reported on Schedule K, line 8c.
Built-in gains: Schedule B Item 8 asks about a corporation that was a C corporation before its S election, or that acquired an asset with a basis determined by reference to a C corporation, and that has net unrecognized built-in gain. If the tax applies, it is computed on Schedule D (Form 1120-S), Part III, and carried to line 23b. The recognition period is set in the Schedule D instructions for the year you file, so pull them rather than reusing an old figure.
Failure mode: Item 8 is answered no because nobody reviewed the company's C corporation history. Fix it by reading the original Form 2553 election and the first-year balance sheet before the final return is prepared.
Reconcile distributions, AAA and shareholder loans
Schedule K, line 16d reports distributions to shareholders, with an attached statement if required, and line 16e reports repayments of loans from shareholders. The Schedule M-2 instructions recommend that the AAA be maintained by all S corporations. A distribution reduces the AAA but not below zero, and the instructions give the order for the other accounts after that.
Schedule L, line 19 for loans from shareholders should generally reconcile to the amounts on each Schedule K-1, as the Item I instructions describe. A shareholder loan is often repaid out of the final distribution, so document each repayment before the distribution is booked.
Failure mode: a loan that was never repaid and never shown on the K-1 leaves Schedule L and the shareholder's return in disagreement. Fix it with a loan roll-forward for each shareholder, signed off by the client before the K-1s are prepared.
Give each shareholder a final Schedule K-1
The instructions say the corporation must provide each Schedule K-1 to each shareholder on or before the day on which the Form 1120-S is required to be filed. Keep a copy for the corporation's records. Treat the original due date as the K-1 date unless you have confirmed otherwise in writing.
Each shareholder's share is figured daily, based on the stock held on each day, under Item G. A shareholder who terminated the entire interest during the final year may be covered by an election to allocate items as if the year were two tax years. Decide that election before the K-1s are drafted.
Failure mode: the K-1 shows the liquidating gain on the wrong line because the Form 4797 never reached the preparer. Fix it by tying each K-1 to the Schedule K totals before release.
Handle the state final-year return
California is a useful worked case. The FTB page says the annual tax for S corporations is the greater of 1.5% of the corporation's net income or $800. The same page says S corporations should file Form 100S.
The same FTB page does not address the final year. Ask FTB whether the minimum tax applies to the year of dissolution before you bill the client for it, and do not assume it is prorated or waived.
Decision rule: keep a state table in the file with one row per state and columns for the form, the due date, the minimum tax, whether a separate dissolution or surrender filing is needed, and the signer. Fill it from each state revenue site, not from a summary article.