See your real ESPP gain and tax bill before you sell.

How to use this ESPP calculator

Enter your offering date price, the FMV on your purchase date, the actual price you paid (usually 85% of the lower of the two), how many shares you bought, and what you sold (or plan to sell) them for. The calculator automatically determines whether your sale is a qualifying or disqualifying disposition and shows an estimated tax breakdown — estimated ordinary-income and capital-gain components, plus payroll and state estimates — so you can see your net profit and effective tax rate before you act.

What is an ESPP?

An Employee Stock Purchase Plan (ESPP) lets you buy company stock at a discount — typically 15% — through payroll deductions. Most plans use a "lookback" feature: you pay 85% of the lower of the stock price at the start of the offering period or the end (purchase date). This means you can profit even if the stock falls, which is what makes a Section 423 ESPP one of the most reliable benefits offered by public companies.

Qualified (Section 423) vs non-qualified plans

Use the plan type selector to match your plan. Most large U.S. public-company ESPPs are qualified Section 423 plans: the discount income is reported on your W-2 but is generally not subject to FICA (Social Security and Medicare), even in a disqualifying disposition, and holding long enough unlocks the qualifying-disposition tax break. A non-qualified ESPP works differently — the entire purchase-date discount is ordinary income at purchase and is subject to FICA, with no qualifying-disposition treatment. The calculator applies the correct rules for whichever plan you choose.

Qualifying vs. disqualifying dispositions: tax impact

How you are taxed on ESPP shares depends almost entirely on when you sell.

Qualifying disposition (QD)

You must hold shares for more than 2 years from the offering date AND more than 1 year from the purchase date. Ordinary income is generally limited to the lesser of the offering-date discount determined under the plan or the actual gain on the sale — not always the full discount. Any remaining gain is generally long-term capital gain (0%, 15%, or 20%). If the shares are sold at a loss, there is generally no ordinary income and the loss is a capital loss.

Disqualifying disposition (DQ)

If you sell before meeting both holding requirements, the spread between your purchase price and the FMV on the purchase date is taxed as ordinary income (and shows up on your W-2). Only gains above that purchase-date FMV may qualify as capital gains — short-term if you held the shares a year or less after purchase.

Should you sell ESPP shares immediately?

A 15% purchase discount provides a built-in discount at purchase, but the final realized return is not guaranteed because the share price can change before the shares are sold and plan or trading restrictions may delay the sale. If shares could be sold immediately at unchanged fair market value, paying 85% of fair value would represent approximately a 17.65% gain on the amount paid before taxes, fees and price movement. Selling promptly can reduce employer stock concentration risk. The trade-off: an immediate sale is a disqualifying disposition, so the purchase-date discount is taxed as ordinary income.

If you believe in your employer's stock and are in a low bracket, holding for a qualifying disposition can result in lower total taxes. Use the "what if you had held?" comparison in the calculator above to see the dollar difference in your specific situation — and weigh it against the market risk of staying concentrated in a single stock.

What this calculator does not include

This is a simplified educational estimate. It applies your marginal bracket to the ordinary-income portion and an approximate 0/15/20% long-term rate based on your income, but it does not model the Net Investment Income Tax, the alternative minimum tax, or the precise interaction of your other deductions and credits. Payroll-tax (FICA) treatment can depend on the plan and the transaction — qualified Section 423 discount income is generally not subject to FICA, while non-qualified ESPP income generally is — and this calculator does not fully model the Social Security wage base or all payroll-tax circumstances. State rules vary widely and the state figure is a simplified effective-rate estimate. Treat the result as an estimate and confirm specifics with a qualified tax professional before you sell.

Sources: IRS Publication 525 (ESPP compensation treatment) and the IRS Section 423 stock-plan FAQ.