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409A vs 409B: Key Differences Every Startup Founder Must Know

Section 409A of the IRC governs nonqualified deferred compensation for employees, establishing the rules for stock option pricing that startups must follow. Section 409B was a proposed (but never enacted) extension of similar rules to independent contractors. Today, only Section 409A is law — Section 409B does not exist as enforceable legislation.

Published April 24, 2026
3 min read

Key Takeaways

  • Section 409A is enacted law — it governs stock options and deferred compensation for employees
  • Section 409B was a legislative proposal that was never passed into law
  • For startup equity purposes, only 409A is relevant — there is no 409B compliance requirement
  • 409A's rules require options to be granted at fair market value to avoid a 20% excise tax
  • Some advisors and contractors mistakenly believe 409B applies to them — it does not
  • The confusion between 409A and 409B is common but easily resolved: focus entirely on 409A

The Short Answer: Only 409A Is Law

When founders and startup employees search for "409A vs 409B," they are often trying to understand whether their equity compensation arrangements are subject to one rule, the other, or both. The answer is straightforward: only Section 409A is enacted law. Section 409B was a proposed legislative extension that was discussed but never passed by Congress. It has no legal force.

For all practical purposes, there is no "409B" that affects your startup's equity compensation. Every conversation about startup stock options, strike prices, and IRS compliance is a conversation about Section 409A exclusively.

What Is Section 409A?

Section 409A of the Internal Revenue Code was enacted as part of the American Jobs Creation Act of 2004 and became effective in 2005. It establishes comprehensive rules for nonqualified deferred compensation — including stock options granted to employees, directors, and certain contractors of private companies.

The core requirement under 409A is that stock options must be granted with a strike price at or above the fair market value (FMV) of the underlying stock on the grant date. For private companies, FMV must be determined by an independent qualified appraiser — the 409A valuation. Options granted below FMV trigger immediate income tax on the spread at vesting, plus a 20% federal excise tax.

What Was Proposed Section 409B?

Section 409B was proposed in the context of legislative efforts to close perceived tax loopholes for independent contractors. The proposal would have applied rules similar to 409A's timing and payment restrictions to nonqualified deferred compensation arrangements with independent contractors.

Key points about proposed Section 409B:

  • It was never passed — it appeared in committee discussions and draft legislation but was not enacted
  • It would have targeted large deferred compensation arrangements with independent contractors, not startup employees
  • It had nothing to do with stock option pricing or fair market value appraisals
  • Even if it had been enacted, it would not have replaced or modified 409A

Why Does the Confusion Exist?

  • Numerical proximity: 409A and 409B sound like part of the same regulatory framework
  • Contractor coverage gap: 409A does apply to some contractor arrangements, and some advisers incorrectly invoke "409B" when discussing it
  • Outdated content: Some older articles from the mid-2000s discussed 409B as a pending proposal and continue to circulate

Section 409A and Independent Contractors

While Section 409B never became law, Section 409A does apply to certain deferred compensation arrangements with independent contractors:

  • Stock options granted to contractors must still be priced at FMV to avoid 409A penalties
  • Deferred payment arrangements with contractors may be subject to 409A's six permissible payment triggers
  • Contractors who are significant equity holders may face additional 409A complexity

Summary: Focus on 409A

FeatureSection 409AProposed Section 409B
Legal statusEnacted law (since 2005)Never passed — not law
Applies toEmployees, directors, some contractorsWould have applied to independent contractors
Covers stock optionsYes — strike price must equal FMVNo — not about option pricing
Compliance requiredYes — 409A valuation requiredNo — nothing to comply with
Penalties for violation20% excise tax + ordinary income taxN/A — not enacted

Educational Content — Not Tax or Legal Advice

The information on this page is provided for general educational purposes only. It does not constitute tax advice, legal advice, or a formal valuation opinion. Every company's situation is different — consult a qualified tax adviser, attorney, or certified valuation analyst before making decisions based on this content.

State law may vary. Individual US states may impose additional income tax, excise tax, or reporting obligations on nonqualified deferred compensation and stock options. California, for example, imposes an additional penalty tax of up to 20% on top of federal penalties. Always review applicable state rules with local counsel.

Primary source: IRC Section 409A and the final Treasury Regulations under T.D. 9321 (IRS Internal Revenue Bulletin 2007-19). For the most current IRS guidance, penalties, and safe harbor requirements, refer to the IRS IRC 409A Overview page directly.

Content last reviewed: August 2026. Tax law changes frequently — readers are encouraged to verify current rules with the IRS or a qualified professional before relying on this content.

409A Valuation Pro is not affiliated with, endorsed by, or sponsored by the Internal Revenue Service or any US government agency. IRS, Internal Revenue Service, and related names are trademarks of the US Department of the Treasury.

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