Stock on Sale: The Basics of Your Employee Stock Purchase Plan

Imagine a store that sells you something at 15% off. Now imagine that if the price went up while you were shopping, the store rings you up at the old price anyway, and then takes 15% off that. You would never shop anywhere else. That store exists, it is called an Employee Stock Purchase Plan, and a lot of people walk right past it during open enrollment. Let's fix that.

What is an ESPP?

An ESPP lets you buy your employer's stock through payroll deductions, usually at a discount. You pick a percentage of your paycheck to set aside, the money piles up during an offering period, and on the purchase date the company uses it to buy shares for you.

Most plans at public companies are “qualified” plans under Section 423 of the tax code, which is where the good tax treatment comes from. The law caps the discount so the price you pay can be no lower than 85% of the stock's value, and it caps how much you can buy at $25,000 worth of stock per calendar year, measured at the stock's value when the offering begins.¹ Some companies run nonqualified plans instead, which follow different tax rules, so check which kind you have.

The lookback: the feature that makes ESPPs special

Many plans include a lookback. Instead of taking 15% off the price on the purchase date, the plan takes 15% off the lower of the price at the start of the offering or the price on the purchase date.¹

One important note: not every plan is this generous. The law allows a discount of up to 15%, but some plans offer 10%, 5%, or none at all, and many plans skip the lookback entirely.

Here is a quick example. Your offering starts with the stock at $40. Six months later, on the purchase date, it is trading at $50. With a lookback, your price is 85% of $40, or $34 a share. Say you contributed $10,200 from your paychecks. That buys 300 shares worth $15,000 the moment they land in your account. That is a $4,800 gain on money you only parted with for a few months. Even without a lookback, buying at a 15% discount is an instant 17.6% return on your money (the math: $1 divided by $0.85).

Taxes, part one: nothing happens when you buy

With a qualified plan, buying the shares is not a taxable event.² No tax is due until you sell. The catch is that the tax you eventually owe depends on how long you held the shares, which brings us to the two words every ESPP owner needs to know.

Taxes, part two: qualifying vs. disqualifying

A qualifying disposition happens when you sell more than two years after the offering began and more than one year after you bought the shares.³ Anything sooner is a disqualifying disposition. “Disqualifying” sounds like you broke a rule. You didn't. It just means the tax math works differently.

Disqualifying: The discount you received, measured as the stock's value on the purchase date minus what you paid, is taxed as ordinary income.³ In our example, that is $16 a share, or $4,800. Any change in price after the purchase date is a capital gain or loss.

Qualifying: Your ordinary income is the smaller of two numbers: the discount based on the offering start price, or your actual gain.³ Everything else is a long term capital gain. If you hold our 300 shares long enough and sell at $60, ordinary income is only $6 a share ($40 minus $34), or $1,800. The remaining $6,000 of growth is taxed at long term capital gains rates.⁴

So how much did patience save? Compared with selling at $60 before the holding periods were met, the qualifying sale moved $3,000 out of ordinary income and into long term gains. For someone in the 32% bracket, that is roughly $500 in federal tax. Nice, but not life changing, and you had to hold a single stock for up to two years to earn it.

The trap nobody warns you about

Here is the one that stings. Say you buy at $34 when the stock is worth $50, and three months later it drops to $45 and you sell. That is a disqualifying disposition, so you still have $4,800 of ordinary income based on the $50 purchase date value, even though the stock fell. You also get a $1,500 capital loss, but capital losses only offset $3,000 of ordinary income per year.⁴ The tax on the discount does not shrink just because the stock did.

One more wrinkle: for qualified plans, ESPP income is not subject to Social Security or Medicare tax, and your employer is not required to withhold income tax on it.⁵ That sounds great until April, when the bill shows up with nothing set aside to pay it.

The double tax hiding in your 1099B

Your brokerage's Form 1099B will usually show your cost basis as just the price you paid, $34 a share in our example. It does not include the discount that was already taxed as ordinary income.⁶ If you or your software take that number at face value, you pay tax on the same dollars twice. The IRS instructions for Form 8949 tell you to report the basis as shown and correct it with an adjustment using code B.⁷ Keep the Form 3922 your company sends each year, which lists the offering date, purchase date, prices, and share count you need to get this right.⁸

How to make the most of your ESPP

Participate if your budget allows. A discount of up to 15%, sometimes with a lookback, is one of the best deals in employee benefits. If cash flow is tight, even a small contribution captures the same percentage discount.

Consider selling soon after you buy. Many people take the discount and move on. You pay ordinary income tax on the discount, but you lock in the gain and avoid tying even more of your net worth to your employer. Selling right after the purchase is often called a “quick sale,” and some employers allow it while others require you to hold the shares for a set period first, so check your plan's rules. The tax savings from holding are real, but they are rarely worth betting your discount on one stock.

Watch the concentration. Your paycheck, your bonus, maybe your RSUs, and now your ESPP all depend on the same company. If that sounds familiar, our article on concentrated positions walks through the risks.

Plan for the tax bill. Since nothing is withheld, set aside money for the tax, bump your W4, or make an estimated payment in any year you sell ESPP shares.

Read your plan document. Offering periods, purchase dates, contribution limits, lookbacks, and whether you can drop out midway all vary by company. Five minutes of reading beats a year of surprises.

The bottom line

An ESPP is basically your employer offering you its stock on sale. The discount is the easy part. The tax rules and the temptation to hold too much company stock are where planning pays off. At Swan Wealth, we help you decide how much to contribute, when to sell, and how to keep your employer's stock in its proper place in your plan. If your Form 3922 looks like a foreign language, give us a call.

This is general education, not personalized tax or investment advice. How your ESPP should be handled depends on your plan terms, tax bracket, state, and the rest of your portfolio, so let's look at your numbers before your next purchase date.

Sources

1. 26 U.S. Code § 423, “Employee stock purchase plans,” Cornell Law School: option price not less than 85% of the lesser of fair market value at grant or exercise, and the $25,000 annual limit measured at fair market value when the option is granted. https://www.law.cornell.edu/uscode/text/26/423
2. IRS, “Topic no. 427, Stock options”: for statutory stock options, which include ESPP options, you generally do not include any amount in income when you receive or exercise the option. https://www.irs.gov/taxtopics/tc427
3. IRS, Publication 525, “Taxable and Nontaxable Income,” Employee Stock Purchase Plan section: holding period of the later of one year after transfer or two years after grant, ordinary income on qualifying and disqualifying dispositions. https://www.irs.gov/publications/p525
4. IRS, “Topic no. 409, Capital gains and losses”: long term treatment for assets held more than one year, and net capital losses deductible against other income up to $3,000 per year ($1,500 married filing separately), with the rest carried forward. Examples in this article were calculated by Swan Wealth and are federal income tax only. https://www.irs.gov/taxtopics/tc409
5. 26 U.S. Code § 3121(a)(22), excluding ESPP transfers and dispositions from wages for Social Security and Medicare, and 26 U.S. Code § 421(b), stating no income tax withholding is required on disqualifying dispositions. https://www.law.cornell.edu/uscode/text/26/3121 and https://www.law.cornell.edu/uscode/text/26/421
6. Charles Schwab, “Employee Stock Purchase Plan (ESPP) Taxes: A Guide”: ordinary income calculations and the 1099B cost basis that does not include ordinary income already recognized. https://www.schwab.com/learn/story/espp-taxes
7. IRS, “Instructions for Form 8949”: correcting an incorrect Form 1099B basis with code B and an adjustment in column (g). https://www.irs.gov/instructions/i8949
8. IRS, “Instructions for Forms 3921 and 3922”: Form 3922 reports the grant date, exercise date, fair market values, price paid, and shares transferred under an ESPP. https://www.irs.gov/instructions/i3921