QSBS Explained: Section 1202 for Software Founders

This guide explains what QSBS is, the conditions to qualify, and what the One Big Beautiful Bill Act changed in 2025. It includes a worked example and the common ways founders lose the benefit. It is written for founders of software and SaaS businesses who are preparing an exit. It is general information, and the specifics belong with a qualified tax advisor or CPA.

Key takeaways

• QSBS under Section 1202 can exclude gain on the sale of qualifying C-corp stock from federal tax, up to a cap.
• The 2025 tax law added a tiered exclusion for stock issued after July 4, 2025: 50% at three years, 75% at four years, 100% at five years.
• The per-issuer exclusion cap rose from $10M to $15M, and the company gross-assets ceiling rose from $50M to $75M.
• Software businesses typically qualify as an eligible trade, while many service businesses are excluded.
• QSBS is often lost through entity choice, timing or redemptions, so eligibility belongs in exit planning early.

Table of contents

1. What QSBS is
2. The core requirements
3. What changed in 2025 under OBBBA
4. Worked example: excluding gain on a sale
5. Where founders commonly lose QSBS
6. How QSBS fits exit planning
7. Frequently asked questions
8. Sources

What QSBS is

QSBS is stock in a qualifying US C-corporation that, when sold after a required holding period, lets the seller exclude some or all of the gain from federal income tax. The rule lives in Section 1202 of the Internal Revenue Code. It was written to reward long-term investment in small operating businesses.

Why it matters for software founders

Software and SaaS companies are frequently organized as C-corporations, especially when they raise venture capital. That entity choice is exactly what QSBS requires. A founder who built inside a C-corp and meets the other tests can face a dramatically lower federal tax bill on an exit than a founder in a pass-through entity.

The benefit is large enough to shape deal structure. Because QSBS applies to a stock sale, it interacts with how a transaction is built, which is why it belongs in pre-exit tax planning rather than a late scramble at the letter of intent.

The core requirements

QSBS applies only when a specific set of conditions is met at issuance and through the holding period. Missing any one of them can disqualify the stock, so each deserves a check with a tax advisor well before a sale.

The core requirements are:

1. C-corporation. The issuer must be a domestic C-corp at issuance and during substantially all of the holding period. S-corps, LLCs and partnerships do not qualify.
2. Original issuance. The stock must be acquired at original issue, in exchange for money, property or services, not bought from another shareholder.
3. Gross-assets test. The corporation's aggregate gross assets must have been at or below the ceiling at and immediately after issuance. Crossing the ceiling later does not undo qualification for stock already issued.
4. Active business test. At least 80% of assets must be used in a qualified active trade or business during substantially all of the holding period.
5. Eligible business type. Certain service fields are excluded, including health, law, accounting, consulting, financial services and any business whose principal asset is the reputation or skill of its employees. Software companies generally sit outside these excluded categories.
6. Holding period. The stock must be held for the required period, which the 2025 law restructured into tiers described below.

Software as an eligible trade

The eligible-business test is where many founders in professional services fall out, and where software founders usually stay in. A product software or SaaS business that sells a product, rather than the personal services of its people, generally counts as a qualified trade. The line can blur for services-heavy or consulting-adjacent models, which is a point to confirm with a CPA.

What changed in 2025 under OBBBA

The One Big Beautiful Bill Act rewrote several QSBS parameters for stock issued after July 4, 2025. The changes make the benefit reachable sooner and larger, while the prior rules still govern stock issued on or before that date.

The new tiered exclusion

For stock issued after July 4, 2025, Section 1202 now provides a tiered exclusion by holding period rather than a single five-year cliff. The table sets out the two regimes.

Higher caps and a higher asset ceiling

Two limits also rose. The per-issuer exclusion cap increased from $10M to $15M, indexed for inflation for tax years after 2026. The company gross-assets ceiling increased from $50M to $75M, widening the set of companies whose stock can qualify. The cap remains the greater of $15M or 10 times the shareholder's basis, so founders with meaningful basis can exclude more than $15M.

Worked example: excluding gain on a sale

The effect is clearest with numbers. A founder holds QSBS in a C-corp software company issued after July 4, 2025, with a basis near zero, and sells five years later for a gain of $12M. The federal long-term capital gains rate for a high earner is 20%, plus the 3.8% net investment income tax, so 23.8% without QSBS.

State treatment is separate and varies. Some states conform to QSBS, others do not tax the excluded gain the same way, so the state result must be checked for your residency.

Where founders commonly lose QSBS

QSBS is frequently forfeited through decisions that seemed unrelated to tax at the time. Each of these is avoidable with early planning.

The most common ways the benefit is lost:

1. Wrong entity. Operating as an S-corp, LLC or partnership means no QSBS. Only C-corp stock qualifies, and only from the point of a valid C-corp issuance.
2. Late conversion. Converting from an LLC or S-corp to a C-corp can start the QSBS clock, but only gain accruing after the conversion and issuance qualifies. Pre-conversion appreciation does not.
3. Redemptions. Significant stock buybacks by the company around the issuance window can disqualify the stock under the redemption rules.
4. Holding period. Selling before the relevant three, four or five-year mark reduces or eliminates the exclusion under the tiered schedule.
5. Asset ceiling at issuance. If aggregate gross assets exceeded the ceiling when the stock was issued, that issuance does not qualify, even if the company was smaller later.

The pattern is that eligibility is set early and preserved through the holding period. That is why a review belongs years before a sale, not during it.

How QSBS fits exit planning

QSBS sits at the intersection of entity structure, timing and deal design, which places it early in any exit plan. A founder who confirms eligibility with a CPA can then align the sale timeline and structure to preserve it.

Timing is the most controllable lever. Where a sale is flexible, holding to the next tier, or to the five-year mark, can change the after-tax outcome by a large amount. That trade-off between timing and price is part of the wider exit planning picture and the mechanics in the sell your business hub.

Deal structure matters too, because QSBS attaches to a stock sale. Buyers often prefer asset deals for the step-up in basis, which can conflict with a seller's QSBS position. A structured, competitive process gives a seller the standing to negotiate a structure that protects the benefit.

Last updated on July 27, 2026.