If your company was acquired and you received the acquirer’s stock for your QSBS in a qualifying tax-free reorganization, Section 1202(h)(4) can preserve QSBS treatment and the original acquisition date. When the exchange-date gain cap applies, later appreciation is outside the Section 1202 exclusion. The cap does not apply if the corporation issuing the replacement stock is a qualified small business at the time of the exchange. Other Section 1202 requirements and limits still apply.
This post is part of our Complete Guide to QSBS and Section 1202.
The general rule: your QSBS survives the exchange
Section 1202 ordinarily requires original issuance — you must have acquired your stock directly from the corporation for money, property (other than stock), or services. Stock you receive in exchange for other stock normally fails that test. Without a special rule, every stock-for-stock acquisition would destroy QSBS status.
Section 1202(h)(4)(A) is that special rule. In a transaction described in Section 351 or a reorganization described in Section 368, stock received in exchange for QSBS is treated as QSBS "acquired on the date on which the exchanged stock was acquired." Two things follow:
- The acquirer's stock is treated as QSBS in your hands, even if the acquirer is not a qualified small business.
- Your holding period carries over. If you acquired your original shares in 2021 and the acquisition closed in 2024, your clock has been running since 2021.
For Section 351 exchanges, Section 1202(h)(4)(D) imposes an additional condition: immediately after the transaction, the corporation issuing the new stock must own, directly or indirectly, stock representing control of the corporation whose stock was exchanged, within the meaning of Section 368(c). This additional Section 1202 condition does not apply to Section 368 reorganizations, which must still satisfy the requirements of the applicable reorganization provision.
The trap: the exchange-date gain cap
Here is the part that surprises people at sale time. Section 1202(h)(4)(B) limits the exclusion on the replacement stock to "the gain which would have been recognized at the time of the transfer" — that is, the gain built into your shares on the date of the exchange.
When this cap applies, appreciation after the exchange is not eligible for the Section 1202 exclusion. The exchange-date built-in gain sets an additional ceiling; it does not guarantee that all gain within that ceiling is excludable.
The cap does not apply if the corporation issuing the replacement stock is a qualified small business at the time of the exchange. In that case, later appreciation may also qualify, subject to the remaining Section 1202 requirements and limits. Verify the issuer’s statutory qualification at the exchange; describing the buyer as a small C corporation is not enough.
The cap is also sticky. Under Section 1202(h)(4)(C), once the limitation attaches, it is measured as of the first exchange to which it applied. A second reorganization doesn't reset it.
A worked example
Say you exercised options for fully vested QSBS on January 15, 2021, with a basis of $10,000. Your company was acquired in a qualifying Section 368 stock-for-stock reorganization in 2024, when your shares were worth $2,000,000. On September 1, 2026, you sell the acquirer stock for $3,500,000. Assume the buyer was not a qualified small business at the exchange, your basis stayed $10,000, your available per-issuer eligible-gain limit covers the $1,990,000 built-in gain, and all other Section 1202 requirements are met.
- Holding period: January 15, 2021 to September 1, 2026 is more than five years, including the carried-over holding period. The actual dates matter; a sale somewhere in 2026 does not by itself establish that shares acquired somewhere in 2021 have been held more than five years.
- Excludable gain: capped at the exchange-date built-in gain — $1,990,000 ($2,000,000 value less $10,000 basis).
- Taxable gain: $1,500,000 of post-exchange appreciation under these assumptions. If the available per-issuer eligible-gain limit were lower, some exchange-date gain could also remain taxable.
Two dates do different jobs. For the exclusion percentage and the $10 million versus $15 million dollar-limit component, use the statutory acquisition date, including applicable holding-period tacking under Section 1202(a)(6)(B). This example retains its 2021 acquisition date, so the 100% exclusion requires more than five years. Qualifying stock acquired after September 27, 2010 and on or before July 4, 2025 follows that rule; older acquisitions can remain in the historical 50% or 75% regimes. Post-July 4, 2025 acquisitions can receive 50%, 75% or 100% exclusions after at least three, four or five years, respectively. The eligible-gain limit is applied before the exclusion percentage and includes the ten-times-basis alternative and applicable prior-use, coordination and marital rules. Separately, the gross-assets ceiling follows issuance: $50 million for stock issued on or before July 4, 2025 and $75 million for stock issued afterward. The $15 million dollar amount and $75 million ceiling are indexed beginning in 2027. A later replacement issuance does not automatically change a tacked acquisition date. See Don't Accidentally Disqualify Your QSBS by "Resetting" It for why you cannot exchange your way into the new regime. Sources: Section 1202(a), (b) and the 2025 effective-date notes.
Document the exchange-date value at closing
The exchange-date cap makes one number decisive years after everyone stopped thinking about the deal: the fair market value of your shares on the exchange date.
At sale, you (and eventually an examiner) need to establish three things: that the original shares were QSBS, that the exchange qualified under Section 351 or 368, and what the built-in gain was on the exchange date. The first two are documentation questions. The third is a valuation question — and if you didn't capture the deal-date value when the deal happened, you are reconstructing it from old board materials, 409A reports, and merger documents years later.
If you hold acquirer stock received for QSBS, the time to paper this is now, not at sale. A written attestation memorializing original QSBS status, the reorganization, and the exchange-date value is a useful part of the substantiation file. See What a QSBS Attestation Letter Must Say and our QSBS attestation service.
Cash deals are different
If you were cashed out, there is no Section 1202(h)(4) issue — the sale was a taxable disposition of your QSBS itself.
Receiving buyer stock does not by itself make an acquisition tax-deferred. If the exchange does not qualify for nonrecognition, gain can be recognized at closing based on the cash and fair market value of the stock or other property received, even if you receive no cash. Evaluate any available Section 1202 exclusion at that time; Section 1202(h)(4) does not carry QSBS treatment over in a fully taxable exchange. See Section 1001.
- Holding period met: for stock acquired on or before July 4, 2025, more than five years is required; the applicable historical exclusion percentage still matters. For stock acquired afterward, the 50%/75%/100% tiers require at least three/four/five years. Apply the statutory acquisition-date rules, eligible-gain limit and other qualification requirements.
- Holding period not met: Section 1045 may defer gain if a noncorporate taxpayer sells QSBS held for more than six months, elects rollover treatment and purchases qualifying replacement stock within the 60-day period beginning on the sale date. Reinvesting the full proceeds is generally necessary to defer the full gain. The replacement stock and transaction must meet the remaining requirements; an early exit alone does not establish eligibility. See Section 1045 Rollover: How to Defer QSBS Gains. See also Section 1045(a).
In a reorganization involving both stock and cash or other property, Section 356(a)(1) generally recognizes the lesser of the realized gain or the cash plus the fair market value of other boot received, before considering any available Section 1202 exclusion. Section 356(a)(2) can treat some or all of that recognized gain as a dividend; the dividend portion is not eligible for the Section 1202 exclusion. Analyze the recognized exchange gain and the replacement stock separately. Review any consideration election and its deadline before closing. See Section 356(a).
Don't confuse this with same-company conversions
Section 1202(f) applies when stock is acquired solely through conversion of other stock of the same corporation that was already QSBS in your hands—for example, qualifying preferred stock converting to common. It preserves QSBS treatment and carries over the holding period; it does not turn non-QSBS into QSBS merely because the conversion occurs within one company. A conversion covered by Section 1202(f) does not itself impose the cross-corporation exchange-date cap in Section 1202(h)(4)(B). See Section 1202(f).
The holding-period clocks, briefly
For shares originating as employee equity, identify when the original holding period began:
- Exercise into substantially vested stock: The holding period generally begins just after the stock is transferred on exercise, not when the option is granted.
- Restricted stock and early-exercised NSO shares subject to Section 83: Without a timely Section 83(b) election, the holding period generally begins just after substantial vesting. With a timely election, it generally begins just after transfer.
- Early-exercised ISOs: A Section 83(b) election operates for AMT purposes only; it does not establish the regular-income-tax treatment. Analyze the ISO rules separately.
- RSUs: the clock starts at share delivery.
See Treas. Reg. §1.83-4(a); Treas. Reg. §1.422-1(b), Example 2.
The tacked period from the exchange is added on top of whichever clock applies to your original shares.
The Washington layer
For Washington residents, gain excluded under §1202 is outside the capital-gains tax base. Gain remaining taxable after the exchange requires its own exclusion-cap, deduction and rate calculation. A large payout can affect federal estimates. Keep Washington’s capital-gains payment rules separate from the new income-tax estimates, which are not required before July 1, 2029. See the capital-gains guide and the estimated-payment guide.
What to do if this is you
- Confirm your original shares were QSBS and how the acquisition was structured (the merger agreement's tax section will say whether it was intended as a Section 368 reorganization).
- Establish the exchange-date value of your shares and paper it.
- Determine whether the replacement issuer was a qualified small business at the exchange. If the exchange-date cap applies, calculate it using the built-in gain at the first exchange to which the cap applied, then apply the other Section 1202 requirements and limits.
- If a sale or tender is coming, model the taxable post-exchange gain, federal estimated payments and the separate Washington payment obligations. Do not use the income-tax estimate schedule as the capital-gains tax schedule.
If you are holding acquirer stock that used to be QSBS and a liquidity event is approaching, schedule a 20-minute call and we can walk through where your shares sit.
This post is general information, not legal or tax advice for your situation. The application of Sections 1202, 351, and 368 to any particular acquisition depends on the deal documents and your specific facts.
