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ESPP Qualifying Disposition Tax Calculator

A qualifying §423 ESPP sale gets a tax break: part of your gain stays at long-term capital-gain rates instead of ordinary income. Enter your offer date, purchase date, and sale price to see exactly how the IRS splits the proceeds — and how much you saved by holding long enough.

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Tax year 2026 · Last updated May 10, 2026

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Did your ESPP sale qualify for long-term capital gains?

A qualifying disposition (held 2 years from grant + 1 year from purchase) splits your gain — ordinary income capped at the smaller of the discount or actual gain, plus long-term capital gain on the rest. The split is worth thousands at high brackets. (IRC § 423)

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Qualifying disposition 42 mo from offer, 36 mo from purchase

$13,943 total tax

✓ Qualifying treatment saves you $900 vs. selling as a disqualifying disposition.

Ordinary income

$7,500

Long-term capital gain

$40,000

Net proceeds after tax

$33,557

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Show the math
Purchase price / share$85.00
Ordinary income / share$15.00
Capital gain / share$80.00
Gross sale proceeds$90,000
Marginal federal rate (ordinary)24.0%
Federal LTCG rate15.0%
Marginal state rate12.30%
Federal tax on ordinary$1,800
Federal LTCG tax$6,000
NIIT (3.8%)$300
State tax$5,843
Total tax$13,943
Disqualifying-disposition tax (comparison)$14,843

How it works

  1. Enter your offering and purchase details. Type the offer-date FMV, purchase-date FMV, plan discount (typically 15%), and the number of shares you bought.
  2. Add your sale price and dates. Enter the per-share price you sold at, plus the offer / purchase / sale dates. The calculator checks both holding-period rules (>2 years from offer, >1 year from purchase).
  3. Add your wages and state. YTD wages and pre-tax deductions size your marginal rate; state tax uses your residence state (or override with a custom rate).
  4. Read the breakdown and savings. See ordinary-income vs. LTCG split, federal + state tax owed, and the difference vs. selling as a disqualifying disposition.

Frequently asked questions

What makes an ESPP sale a “qualifying disposition”?

Two holding rules must both be met: at least 2 years from the offering/grant date AND at least 1 year from the purchase date (IRC §423(a)(1) and §423(a)(2)). Miss either one and the sale is a disqualifying disposition with worse tax treatment. See IRS Publication 525 (Taxable and Nontaxable Income), section "Employee Stock Purchase Plan."

How is the ordinary income calculated on a qualifying sale?

Per IRC §423(c), ordinary income is the LESSER of (a) the discount available at grant — for a typical 15% discount plan, that's grant-date FMV × 15% — or (b) your actual gain (sale price minus your purchase price). Anything above that ordinary-income piece is long-term capital gain. Brokers report the grant-date FMV in Form 3922 Box 2 and the deemed option price in Box 4.

How is the purchase price computed?

For a §423 plan with lookback: purchase price = the lower of (offer-date FMV, purchase-date FMV) × (1 − discount), per the standard plan terms allowed under Treas. Reg. §1.423-2. Plans without lookback set both FMVs equal — enter the same value in both fields.

What is the disqualifying disposition comparison?

On a disqualifying sale, ordinary income is the full bargain element on purchase date (purchase-date FMV − purchase price), uncapped (per IRC §421(b)). Any further gain is short-term or long-term capital gain depending on holding from purchase. The calculator computes both so you can see the dollar value of the qualifying tax break.

Does this include state tax?

Yes — at your state’s top marginal rate by default, with a manual override. Most states (including California per FTB Pub 1004) tax both the ordinary-income piece and the long-term capital gain at ordinary rates with no preferential LTCG treatment.

Does it include NIIT?

Yes. The 3.8% Net Investment Income Tax (IRC §1411) is applied to the long-term capital-gain portion when MAGI exceeds the statutory threshold ($200k single / $250k MFJ / $125k MFS). Thresholds are not inflation-indexed.

What about a sale below my purchase price?

Ordinary income is zero in that case (you can’t recognize ordinary income greater than your actual gain, per the §423(c) lesser-of rule), and you have a long-term capital loss equal to sale price − purchase price reportable on Schedule D.

Is this tax advice?

No — it’s an estimate based on IRS Pub 525, IRC §423, and your inputs. It does not consider AMT, multi-state residency, wash-sale interactions, or other facts a CPA would catch. For real money decisions, talk to a licensed tax professional.

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How the math flows

ESPP qualifying disposition formula chain: discount (FMV at grant − purchase price) → ordinary income = lesser of discount OR actual gain (IRC §423) → capital gain = sale − ordinary − basis (IRC §1) → total tax = ordinary · marginal + LTCG · 0–20%
How the math flows — every step cites the IRC section that controls it.

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