HenryCalc
ESPP calculator
Calculate your employee stock purchase plan discount, shares and tax split by disposition type.
How an ESPP works
An employee stock purchase plan (ESPP) lets you set aside payroll money to buy company stock at a discount, often 15%. The best plans add a lookback: you buy at a discount off the lower of the price at the start of the offering period or the price on the purchase date. That combination can produce a large, near-guaranteed gain the moment shares are purchased.
What this calculator estimates
Enter the offering price, the purchase-date price, your discount, how much you contributed, and your eventual sale price. The tool computes the price you actually paid, the shares bought, and how the gain splits between ordinary income and capital gain depending on whether your sale is qualifying or disqualifying.
Qualifying vs disqualifying
The split matters because ordinary income is taxed at your marginal rate while long-term capital gains are taxed lower. A disqualifying disposition (sold before meeting the holding periods) treats the entire purchase-date discount as ordinary income. A qualifying disposition treats only the smaller offering-date discount as ordinary income and the remainder as a capital gain. The trade-off is holding concentrated employer stock for longer to get there.
Frequently asked questions
- What is an ESPP lookback?
- A lookback lets you buy at a discount off the lower of the price at the start of the offering period or the price on the purchase date. Combined with the discount, it can make an ESPP one of the highest guaranteed returns available to employees.
- When is my ESPP discount taxed?
- The discount is always ordinary income. In a disqualifying disposition (sold before the holding periods), the full discount at purchase is ordinary income. In a qualifying disposition, only the smaller offering-date discount is ordinary income and the rest is a long-term capital gain.
- Should I sell ESPP shares immediately?
- Selling at purchase locks in the discount with no market risk, which many people prefer. Holding for a qualifying disposition can lower the tax rate on part of the gain but adds the risk of holding concentrated employer stock.
Last reviewed January 2026. This calculator provides general educational estimates based on the inputs you enter and simplified assumptions. It is not financial, tax, legal or investment advice, and figures may differ from your actual liability. Verify with a licensed CPA or financial advisor before acting.