A subsidiary is a separate business entity whose major decisions are controlled by another company, called the parent, which typically holds more than 50 percent of the voting shares. Understanding how subsidiaries work means looking at three things together: who owns and controls the entity, how the legal wall between parent and subsidiary is maintained, and how the tax rules shift with the ownership percentage. The subsidiary signs its own contracts, carries its own debts, and files under its own tax ID, but the parent sets the strategic direction and picks the people who run it.
What Ownership Percentage Actually Determines
The parent’s stake in the subsidiary is not just a number on a cap table. It decides how much say minority shareholders have, whether the two companies can file taxes together, and how dividends between them are treated.
A wholly-owned subsidiary is one where the parent holds 100 percent of the voting stock and answers to no outside shareholders. When ownership sits between 50 and 100 percent, the parent still controls the board and strategy, but minority shareholders retain rights that constrain some decisions. A holding company is a parent whose whole purpose is owning stock in other businesses rather than making or selling anything itself. Subsidiaries under the same parent are called sister companies; they share an owner but run independently, often kept separate on purpose so that different product lines, regions, or risk profiles sit in their own legal containers.
One structural limit is worth knowing up front: an S corporation cannot have a corporation as a shareholder, so a corporate parent cannot own an S corp subsidiary.1Internal Revenue Service. S Corporations If pass-through tax treatment is the goal for a subsidiary, an LLC is the usual answer. C corporations can own other C corporations without restriction.
How the Parent Controls the Subsidiary
Control does not usually mean the parent’s executives run the subsidiary directly. It means the parent uses its voting power to appoint the subsidiary’s board of directors, and the board then hires officers who handle daily operations. Local leadership manages employment, vendors, and operations. The parent provides oversight and strategic direction.
That distinction matters legally. The subsidiary should hold its own board meetings, keep its own minutes, and make decisions through its own documented processes. If the parent reaches past the board and runs the subsidiary as if it were an internal department, the courts can treat it that way, with expensive consequences.
The Liability Wall and How It Fails
The biggest reason to use a subsidiary rather than a division is to wall off liability. Because the subsidiary is a separate legal entity, its debts and lawsuits generally stop at its own balance sheet. The Supreme Court confirmed the principle in United States v. Bestfoods, holding that a parent is not liable for the acts of its subsidiaries simply because of the ownership relationship.2Cornell Law Institute. United States v. Bestfoods
That wall, known as the corporate veil, is not automatic. Courts will pierce it and reach the parent’s assets when the subsidiary was not treated as a genuinely independent entity. The most common triggers:
- Mixing funds. Shared bank accounts, or paying the parent’s expenses from the subsidiary’s accounts, signals the two are one business.
- Undercapitalization. If the subsidiary was never given enough money or insurance to cover foreseeable risks, courts may conclude the parent never intended it to stand on its own.
- Ignoring formalities. Skipping board meetings, failing to maintain separate records, or ignoring bylaws suggests the subsidiary exists only on paper.
- Fraud. Using the subsidiary to hide assets, mislead creditors, or dodge existing obligations is the most direct path to losing veil protection.
The defense is documentation. Board resolutions on both sides, separate books, and written records of every intercompany transaction are what preserve the shield when someone tries to knock it down.
How Taxes Work Between Parent and Subsidiary
Every subsidiary needs its own Employer Identification Number from the IRS, even if it ends up filing taxes together with its parent.3Internal Revenue Service. When to Get a New EIN Past that, the tax relationship turns on ownership percentage.
Consolidated Returns at 80 Percent
When a parent owns at least 80 percent of both the voting power and total value of a subsidiary’s stock, the two companies form an affiliated group that can file a single consolidated federal tax return.4Office of the Law Revision Counsel. 26 USC 1504 – Definitions Filing consolidated means every subsidiary in the group consents to the consolidated return regulations.5Office of the Law Revision Counsel. 26 USC 1501 – Privilege to File Consolidated Returns The practical benefit is that losses from one subsidiary can offset profits from another, cutting the group’s overall tax bill. Subsidiaries below that 80 percent line file their own separate returns.
Dividends Received Deduction
Dividends flowing from a subsidiary to a corporate parent would ordinarily be taxed twice, once at the subsidiary and again at the parent. The dividends received deduction softens that, with the size of the deduction tied to ownership:6Internal Revenue Service. Publication 542 (01/2024), Corporations
- Less than 20 percent ownership: 50 percent of dividends deductible.
- 20 percent or more but less than 80 percent: 65 percent deductible.
- 80 percent or more (affiliated group): 100 percent of qualifying dividends deductible, effectively removing the double tax within the group.7Office of the Law Revision Counsel. 26 USC 243 – Dividends Received by Corporations
Each dividend should be backed by a formal board resolution and recorded as a proper distribution, both for tax purposes and to preserve the legal separation.
Transfer Pricing on Intercompany Deals
When a parent and subsidiary sell to each other, share services, or license intellectual property between themselves, the IRS requires the pricing to be what unrelated companies would have agreed to. That is the arm’s length standard. Section 482 of the tax code lets the IRS reallocate income between related companies if the pricing does not meet it.8eCFR. 26 CFR 1.482-1 – Allocation of Income and Deductions Among Taxpayers Written intercompany agreements that spell out the services, the pricing method, and how risks are allocated are the standard way to document compliance.9Internal Revenue Service. Transfer Pricing Documentation Best Practices Frequently Asked Questions (FAQs)
Setting One Up
Formation happens in two layers: the paperwork filed with the state that creates the entity, and the internal documents that govern how it will run.
State-side, the subsidiary needs a unique name and either Articles of Incorporation (for a corporation) or Articles of Organization (for an LLC). Those documents list the entity’s name, principal office, business purpose, and a registered agent with a physical in-state address to receive legal papers. Commercial registered agent services generally run $100 to $300 per year. Filing fees vary widely, roughly $50 to $500 depending on the state and processing speed, and most states return a Certificate of Incorporation or Organization within a few business days.
Internally, a corporation needs bylaws adopted by its board; an LLC uses an operating agreement covering the same ground. Neither gets filed with the state, but both should live in the subsidiary’s records.
If the subsidiary will operate in states other than the one where it was formed, it usually has to register as a “foreign” entity in each of them. Foreign here means out-of-state, not out-of-country. Whether registration is required turns on whether the subsidiary is “doing business” in that state, judged by things like physical presence, employees, and customers. Skipping this can bring penalties, back fees, and the loss of the right to sue in that state’s courts.
Keeping It in Good Standing
Most states require an annual or biennial report to keep an entity in good standing, with updated information on officers, directors, registered agent, and principal address. Fees range from nothing to several hundred dollars a year, and missing the deadline can lead to administrative dissolution.
The governance habits that protect the liability shield are ongoing work: regular board meetings, separate books, adequate capitalization, and paperwork on every parent-subsidiary transaction. These are what keep the veil intact if someone tries to pierce it.
Shutting a Subsidiary Down
Winding up a subsidiary takes action at both the federal and state levels. A corporation adopting a plan to dissolve or liquidate must file IRS Form 966 within 30 days of the resolution, with a certified copy of the plan attached.10IRS.gov. Form 966 Corporate Dissolution or Liquidation A final income tax return is due for the year of dissolution. If the parent owns at least 80 percent, the liquidation can qualify as tax-free under Section 332, meaning the parent recognizes no gain or loss on the assets it receives.11Office of the Law Revision Counsel. 26 USC 332 – Complete Liquidations of Subsidiaries
State-side, the subsidiary pays off debts, fulfills contracts, and distributes what remains before filing a certificate of termination or articles of dissolution with the Secretary of State. Many states also require a tax clearance certificate confirming state taxes are paid. Until that filing is complete, the entity is still on the books and can still owe annual report fees and franchise taxes.
Beneficial Ownership Reporting
The Corporate Transparency Act originally pulled most business entities, including many subsidiaries, into a beneficial ownership reporting regime with the Financial Crimes Enforcement Network. In March 2025, the Treasury Department announced it would not enforce penalties under that rule against U.S. citizens or domestic companies and planned to narrow the rule to foreign reporting companies.12U.S. Department of the Treasury. Treasury Department Announces Suspension of Enforcement of Corporate Transparency Act Against U.S. Citizens and Domestic Reporting Companies As of 2026, enforcement against domestic entities and their owners is suspended, though domestic subsidiaries should watch FinCEN for final rulemaking.