QSBS Explained: How Founders Skip Capital Gains Tax

A new venture fund is putting a powerful tax break back in the spotlight, and founders should pay attention. On July 14, Goodfin unveiled a QSBS fund built to help investors target a 0% federal capital gains rate on qualifying startup stock. The launch leans on a rule that quietly grew far more generous in 2025.

QSBS stands for qualified small business stock, and it can let founders and early shareholders exclude a large share of their gains from federal tax. For a young company builder, that difference can be life-changing at exit. So understanding the rules early, before you raise or incorporate, is one of the highest-return moves you can make. It pairs naturally with smart startup funding in 2026 planning.

What QSBS Is and Why It Exists

QSBS comes from Section 1202 of the tax code. Congress created it to reward people who put money and years into small companies. The deal is straightforward. Hold eligible stock long enough, and you can exclude much or all of the gain when you sell.

To qualify, the stock must come from a U.S. C corporation that meets a size test at issuance. You generally must receive the shares directly from the company, not buy them on a secondary market. The company also has to run an active business rather than simply hold investments.

The exclusion has always been valuable, yet many founders overlook it. That is because the benefit only shows up years later, at sale. Planning now protects a payoff that feels distant today.

How the 2025 Rules Changed the Math

The One Big Beautiful Bill Act reshaped QSBS for stock issued after July 4, 2025. The old rule demanded a full five-year hold for any exclusion. The new law adds a tiered schedule, so partial relief arrives sooner.

Two other limits also rose. The company size cap climbed to $75 million in gross assets, up from $50 million. The per-issuer exclusion cap rose to the greater of $15 million, up from $10 million, and it will index for inflation after 2026. In short, more companies qualify, and each shareholder can shelter more.

What This Means for Founders Right Now

Structure matters more than ever. QSBS only applies to C corporation stock, so founders running an LLC or S corporation may want to weigh a conversion. Converting before a big funding round can lock in eligibility and start the clock sooner. This is the kind of tradeoff to model alongside venture debt and equity choices.

Timing and records are the other half. Note the exact date you receive your shares, since the tiers hinge on it. Keep clean documentation showing the company met the size test at issuance. The IRS ultimately decides whether a sale qualifies, so good paperwork protects the benefit.

One caution deserves attention. States do not all follow the federal rule, and a few tax the gain anyway. Check your state treatment before you count on the full break.

How to Think About the Payoff

Treat QSBS as a long game, not a loophole. The rule rewards builders who stay the course, and the tiered schedule now softens the wait. Even a partial exclusion at three or four years can free real cash for your next venture. That optionality also matters if you ever explore how to buy a business down the road.

The practical step is simple. Talk with a qualified tax advisor before your next incorporation or raise. A short planning conversation today can protect millions later. Founders who learn these rules early tend to keep far more of what they build.

QSBS Frequently Asked Questions

Who can claim QSBS? Founders, employees, and investors who hold qualifying C corporation stock they received at original issuance may claim it, subject to the holding period and dollar caps.

Does QSBS erase all taxes? No. It targets federal capital gains on eligible stock, and state rules vary. Other taxes and situations can still apply.

What is the fastest way to lose eligibility? Holding the wrong entity type is common. QSBS needs C corporation stock, so an unconverted LLC will not qualify.