What Is a QSub? Election, Filing, and Termination

A QSub election is the filing an S corporation makes on IRS Form 8869 to have a 100%-owned domestic subsidiary treated as a Qualified Subchapter S Subsidiary, which means the subsidiary is disregarded for federal income tax purposes and its income, deductions, assets, and liabilities are reported directly on the parent’s single Form 1120-S.¹ The subsidiary keeps its separate legal existence under state law and the liability protection that goes with it; what disappears is the second federal corporate return.

Who Qualifies to Make the Election

Four conditions have to be satisfied before a subsidiary can be a QSub, and all four must hold at all times after the election. The parent must be a valid S corporation with its own S election in effect. The subsidiary must be a domestic corporation. The subsidiary must not be an “ineligible corporation,” a category that covers certain financial institutions using the reserve method for bad debts, insurance companies taxed under Subchapter L, and Domestic International Sales Corporations (DISCs) or former DISCs. And the parent must own 100% of the subsidiary’s stock.²

The 100% ownership requirement is absolute. If a single share ends up with anyone other than the parent, QSub status terminates immediately. Some instruments that look like equity don’t count as “stock” for this test, though. Obligations that fall under the straight-debt safe harbor, or that otherwise wouldn’t be treated as a second class of stock under the S corporation rules, are disregarded when measuring ownership.³ Options, warrants, and convertible debt that satisfy that standard will not break the election.

One point of frequent confusion: the subsidiary itself does not need to independently meet all S corporation requirements. The 100-shareholder cap and the one-class-of-stock rule apply to S corporations, not to QSubs. Because a QSub has one shareholder by definition, those limits are irrelevant. The statutory test is just the four items above.²

Filing Form 8869

The parent S corporation makes the election by filing IRS Form 8869, Qualified Subchapter S Subsidiary Election. The form asks for the legal name, address, and EIN of both the parent and the subsidiary, and an authorized officer of the parent, such as the president or treasurer, must sign it.¹ If you want QSub status for more than one subsidiary, file a separate Form 8869 for each.⁴

Timing Window

The requested effective date on the form cannot be more than 12 months after the filing date or more than two months and 15 days before the filing date. File too early, and the IRS automatically resets the effective date to 12 months after filing. File too late, and the election is generally treated as late, with the effective date pushed forward to two months and 15 days before you actually filed.⁴

For a newly formed subsidiary, enter the formation date as the requested effective date on line 11.

Where to Send It

For an existing subsidiary, file Form 8869 with the IRS service center where the subsidiary filed its most recent return. For a brand-new subsidiary whose election is effective at formation, file with the service center where the parent filed its most recent return.⁴ Service center addresses can change, so verify the current mailing address on the IRS website before sending.

If You Miss the Filing Window

A late filing does not automatically kill the election. Revenue Procedure 2013-30 provides automatic relief without the cost of a private letter ruling if the parent S corporation meets all of the following:⁵

The parent intended to treat the subsidiary as a QSub as of the desired effective date.
The relief request is filed within three years and 75 days after that intended effective date.
The only reason the subsidiary failed to qualify was the untimely election.
The parent has reasonable cause for the delay and acted promptly once the error was discovered.

To request relief, complete Form 8869 and write “FILED PURSUANT TO REV. PROC. 2013-30” across the top. Attach a reasonable-cause statement explaining what went wrong and the steps taken to correct it. An officer must sign a declaration under penalties of perjury confirming that the subsidiary meets all QSub requirements and that all returns have been filed consistently with QSub treatment since the intended effective date.⁵ You can attach the form to the parent’s current-year Form 1120-S, to a late-filed prior-year return (as long as all delinquent returns go in together), or mail it on its own to the applicable service center.

Miss the three-year-and-75-day window and automatic relief is gone. The only remaining path is a private letter ruling, which is costly and uncertain.

What Changes After the Election Takes Effect

A Deemed Liquidation on Day One

As soon as the QSub election becomes effective, the subsidiary is treated as having liquidated into the parent S corporation. Nothing dissolves in real life; the subsidiary continues to exist under state law. For federal income tax purposes, however, the subsidiary’s assets, liabilities, and tax attributes are treated as transferred to the parent in a complete liquidation.¹

That deemed liquidation generally qualifies under Section 332, which makes it tax-free, and the parent takes a carryover basis in the subsidiary’s assets under Section 334(b). A plan of liquidation is deemed adopted immediately before the deemed liquidation unless one was formally adopted earlier.⁶ The step transaction doctrine can apply, so the deemed liquidation should be considered in the context of any broader transaction it’s part of.

One Return, One K-1

After the election, the QSub does not file its own Form 1120-S. All of its income, deductions, and credits flow onto the parent’s return.¹ Shareholders receive one Schedule K-1 reflecting their share of the combined results. Transactions between parent and QSub are ignored for income tax purposes, so a sale of inventory from one to the other is not a recognized event.

Employment and Excise Taxes Still Stand Alone

Disregarded-entity treatment has two important carve-outs. For employment tax purposes under Subtitle C (FICA, FUTA, income tax withholding), the QSub is treated as a separate corporation. It keeps its own EIN, files its own Forms 940 and 941, and issues W-2s to its own employees.⁷

The QSub is also a separate entity for a range of federal excise taxes, including manufacturers’ excise taxes, communications and transportation excise taxes, environmental taxes, and the Affordable Care Act employer shared-responsibility payment under Section 4980H. Overlooking these separate filing obligations is a common compliance error.⁷

Built-In Gains for Former C Corporations

If the subsidiary was a C corporation before the election, the deemed liquidation drags its assets into a five-year recognition period for built-in gains tax under Section 1374. Appreciation that existed at the time of the deemed liquidation is subject to a corporate-level tax at 21% (the highest rate under Section 11(b)) if those assets are sold within five years.⁸ The five-year period was made permanent by the PATH Act of 2015. Net operating loss carryforwards from the subsidiary’s C corporation years can offset recognized built-in gains, so those attributes are worth tracking.

The recognition period runs from the date the assets are acquired by the S corporation (the effective date of the QSub election), not from the date the parent first became an S corporation. That distinction matters when a long-standing S corporation picks up a former C corporation and immediately makes the QSub election.⁸

State Taxes Do Not Always Follow

State treatment of QSubs varies widely, and this is where the structure can produce ugly surprises. Many states follow the federal disregarded-entity approach, but roughly 25 states treat the QSub as a separate entity for state income tax purposes, requiring it to file and report its own income apart from the parent. A smaller group of states go further and treat the QSub as a C corporation at the state level, which exposes the subsidiary to state corporate tax that doesn’t exist federally. A few states have issued no guidance at all.⁹

In practice, a QSub operating in a non-conforming state may need to file a separate state income tax return and pay state franchise or entity-level taxes even though it files nothing federally. Before electing, check every state where the subsidiary does business or owns property. Multistate operations can also create nexus obligations in states the parent never filed in before.

How the Election Ends

Automatic Termination

QSub status ends automatically the moment any eligibility requirement fails. The most common triggers are the parent losing its own S election and any transfer of the subsidiary’s stock to a third party. Termination is effective at the close of the day on which the disqualifying event occurs.¹⁰

Voluntary Revocation

The parent can also end QSub status by filing a revocation statement with the IRS. The statement must include the effective date, and the same timing window used for the original election applies: no more than two months and 15 days before the revocation is filed, and no more than 12 months after.¹⁰

What Termination Looks Like for Tax Purposes

When QSub status ends for any reason, the former QSub is treated as a new corporation that just acquired all of its assets and assumed all of its liabilities from the parent in exchange for its own stock. The parent then holds stock in a separate corporation rather than the underlying assets.¹⁰ Whether this deemed incorporation is tax-free turns on whether it qualifies under Section 351. In most straightforward cases, where the parent keeps 100% control after termination, Section 351 applies and no gain is recognized. By default, the resurrected corporation is a C corporation, and an immediate S election is needed to avoid even a brief period of C corporation taxation.

The Five-Year Lockout

After termination, the former subsidiary generally cannot have a new QSub or S election made for it for five tax years. The IRS Commissioner can waive this restriction with the taxpayer’s consent.¹⁰ One automatic exception exists: if termination happens because 100% of the QSub’s stock is transferred to another S corporation, and the acquiring S corporation makes a new QSub election effective immediately after the transfer, the five-year bar does not apply.¹¹ Outside that scenario, an accidental termination followed by a five-year wait can be painful, which is why monitoring the parent’s S status and the subsidiary’s ownership isn’t something you can set and forget.

1
Internal Revenue Service. About Form 8869, Qualified Subchapter S Subsidiary Election
2
Office of the Law Revision Counsel. 26 USC 1361 – S Corporation Defined
3
Federal Register. Subchapter S Subsidiaries
4
Internal Revenue Service. Instructions for Form 8869 (12/2020)
5
Internal Revenue Service. Revenue Procedure 2013-30 – Relief for Late S Corporation, ESBT, QSST, and QSub Elections
6
Internal Revenue Service. TD 8869 – Final Regulations Relating to Subchapter S Subsidiaries
7
GovInfo. 26 CFR 1.1361-4 – Effect of QSub Election
8
Office of the Law Revision Counsel. 26 USC 1374 – Tax Imposed on Certain Built-in Gains
9
Internal Revenue Service. Chief Counsel Advice
10
eCFR. 26 CFR 1.1361-5 – Termination of QSub Election
11
Internal Revenue Service. Revenue Ruling 2004-85