S Corporation Shareholder Limits

The 100-Shareholder Cap

An S corporation cannot have more than 100 shareholders at any time, per the IRS. This is a hard limit tied to the entity's eligibility for S corporation tax treatment; a corporation that exceeds 100 shareholders automatically loses its S election and reverts to C corporation tax treatment as of the date the limit was exceeded.

The Family Attribution Rule

Congress built in flexibility for family-owned businesses: all members of a family, defined as a common ancestor and all of that person's lineal descendants (and the spouses or former spouses of the common ancestor or any lineal descendant), can elect to be treated as a single shareholder for purposes of counting toward the 100-shareholder cap. The common ancestor generally can't be more than six generations removed from the youngest generation of shareholders being counted. This rule is specifically why a large, multigenerational family business can have dozens of actual stock-holding family members and still easily stay under the 100-shareholder limit.

Who Can Be a Shareholder

Beyond the numeric cap, the IRS restricts what kind of owner can hold S corporation stock at all. Eligible shareholders are individuals, certain qualifying trusts (including grantor trusts, qualified Subchapter S trusts, and electing small business trusts), and estates. Partnerships, most corporations, and nonresident aliens generally cannot be S corporation shareholders. See our guide on whether a nonresident can own an S corporation and whether an LLC can own a corporation for how those specific restrictions work.

The One-Class-of-Stock Rule

An S corporation can only have one class of stock outstanding. Per the IRS, this means every outstanding share has to carry identical rights to distributions and liquidation proceeds; differences in voting rights alone, such as voting and nonvoting common stock, don't violate the rule. A corporation that issues a separate class of stock with different distribution or liquidation rights, intentionally or through a poorly drafted agreement, risks an inadvertent termination of its S election.

What Happens if the Shareholder Rules Are Violated

If an S corporation exceeds 100 shareholders, admits an ineligible shareholder, or ends up with more than one class of stock in substance, the S election terminates, generally effective on the date the violation occurred, and the corporation reverts to C corporation tax treatment going forward. A corporation can sometimes get relief for an inadvertent termination if it corrects the problem and the IRS determines the termination wasn't intentional, but this isn't guaranteed and usually requires a formal request.

Why These Limits Exist

The restrictions on shareholder count and type exist because S corporation income passes through to shareholders' individual returns, and Congress designed the rules for closely held, relatively simple ownership structures rather than for a widely held public company or a structure involving entities the IRS can't easily track tax reporting through, like a foreign partnership. A business that expects to raise capital from venture funds, foreign investors, or a large, dispersed shareholder base typically needs to be a C corporation instead; see our guide on whether a C corporation can elect S corporation status for how the election and its limits interact.

Counting Shareholders in Practice

Each person who directly or indirectly (through an eligible trust) holds stock generally counts separately toward the 100-shareholder limit, except where the family attribution election applies. Keeping an accurate, current shareholder list, including tracking any transfers, gifts, or inheritances of stock, is the practical way to make sure you don't cross the limit without realizing it, particularly as shares pass to a second or third generation of family owners over time.

Review Your Shareholder List Before Any Transfer

Before approving a sale, gift, or inheritance of stock, confirm the recipient is an eligible shareholder type and that the transfer won't push the corporation over 100 shareholders (accounting for any family attribution election already in place). This is a quick check that prevents an expensive, often unnoticed, accidental termination.

Buy-Sell Agreements Can Prevent Accidental Violations

A shareholder or buy-sell agreement that requires board approval before any stock transfer, and that specifically restricts transfers to ineligible holders, is a practical safeguard many closely held S corporations use to avoid an inadvertent termination.

Trust Provisions Need Specific Language

If you're using a trust to hold S corporation stock as part of estate planning, the trust document needs specific language to qualify as an eligible shareholder under one of the IRS's recognized trust categories. A trust drafted without S corporation eligibility in mind can accidentally disqualify the corporation's election.

This Is Not Legal or Tax Advice

Whether a specific trust, family relationship, or stock structure meets these eligibility rules involves technical determinations with real tax consequences if they're wrong. Talk to a tax professional before structuring ownership transfers involving trusts, multiple family branches, or anything beyond straightforward individual ownership.