Stock options/RSU tax planning

Equity compensation is a key part of total pay at public companies, startups, and growth-stage firms. The four main types each have distinct tax rules, holding requirements, and strategic considerations.

64 steps across 12 sections

1. RSUs: Step-by-Step

  • Understand your vesting schedule. Most RSUs vest over 4 years (e.g., 25% per year, or monthly/quarterly after a 1-year cliff). Mark all vesting dates on your calendar.
  • Know your cost basis. Your cost basis = the FMV on the vesting date. Your broker should report this on Form 1099-B, but frequently reports it incorrectly as $0 — always verify.
  • At vesting: automatic tax event. The full FMV of vested shares is reported as ordinary income on your W-2. Your employer withholds taxes via sell-to-cover (selling some shares) or net settlement.
  • Check withholding adequacy. Employers withhold at the flat 22% supplemental rate (37% for amounts over $1M). If your marginal rate is higher, you will owe additional tax at filing.
  • Decide: hold or sell. Selling immediately = no additional capital gains risk. Holding = potential for appreciation but also depreciation and concentration risk.
  • If holding, track holding period. Gains above the vesting-day FMV are short-term capital gains if sold within 1 year, long-term if held over 1 year from vesting.
  • Report correctly on tax return. Ensure your 1099-B cost basis matches your actual basis (vesting FMV). Adjust on Form 8949 if the broker reports $0 basis.

2. ISOs: Step-by-Step

  • Receive the grant. Note the grant date, number of options, exercise (strike) price, and vesting schedule.
  • Wait for vesting. You cannot exercise unvested options (unless early exercise is permitted).
  • Exercise options. You pay the strike price to acquire shares. No regular income tax is due, but the spread (FMV - strike) is an AMT preference item.
  • Calculate AMT exposure. Run AMT projections before exercising. The spread is added to your AMT income. If total AMT exceeds regular tax, you pay AMT.
  • Hold for qualifying disposition. To get LTCG treatment, hold shares >1 year after exercise AND >2 years after grant date.
  • Sell shares. If qualified: entire gain (sale price - strike price) taxed at LTCG rates. If disqualifying: spread at exercise taxed as ordinary income, remainder as capital gain.
  • Claim AMT credit. If you paid AMT in a prior year, you may recover it via the AMT credit (Form 8801) in future years when regular tax exceeds AMT.

3. NSOs: Step-by-Step

  • Receive the grant. Note grant date, number of options, strike price, vesting schedule.
  • Wait for vesting. Options must vest before exercise (unless early exercise is allowed).
  • Exercise options. The spread (FMV - strike price) is immediately taxed as ordinary income and reported on your W-2. FICA taxes (Social Security + Medicare) also apply.
  • Employer withholds taxes. Similar to RSUs, withholding is at the supplemental rate (22% federal). Verify adequacy.
  • Decide: hold or sell. Your new cost basis = FMV at exercise. Additional gains/losses from this point are capital gains.
  • Track holding period. For LTCG treatment, hold shares >1 year from exercise date.
  • Report on tax return. The ordinary income portion appears on your W-2. Capital gains/losses on Form 8949 and Schedule D.

4. ESPP: Step-by-Step

  • Enroll during offering period. Elect a payroll deduction percentage (typically up to 15% of salary, max $25K/year in stock purchases).
  • Payroll deductions accumulate. After-tax dollars are deducted each pay period.
  • Purchase occurs automatically. At the end of the purchase period, shares are bought at the discounted price (typically 85% of the lower of the price at offering start or purchase date).
  • Hold for qualifying disposition. Hold shares >2 years from offering date AND >1 year from purchase date.
  • Sell shares. Qualifying disposition: the discount (up to 15%) is taxed as ordinary income; remaining gain is LTCG. Disqualifying disposition: the spread at purchase is ordinary income; remaining ga...

5. Common Vesting Structures

  • 4-year with 1-year cliff: No vesting for the first year; 25% vests at the 1-year mark; remaining 75% vests monthly or quarterly over 3 more years. Standard at most tech companies and startups.
  • 4-year monthly/quarterly: Equal portions vest each month or quarter over 4 years with no cliff. Common at some public companies.
  • 3-year annual: One-third vests each year. Used at some non-tech companies.
  • Back-loaded: Smaller percentages vest early, larger later (e.g., Amazon's 5%/15%/40%/40% over 4 years).
  • Performance-based (PSUs): Vesting tied to company or individual performance metrics, not just time.

6. Key Vesting Concepts

  • Cliff: The minimum service period before any equity vests. Leaving before the cliff = forfeit all unvested equity.
  • Acceleration: Some plans allow accelerated vesting on termination, change of control, or IPO ("single trigger" or "double trigger" acceleration).
  • Refresh grants: Additional RSU grants made annually to retain employees. These have their own separate vesting schedules, creating overlapping vesting streams.

7. How to Close the Gap

  • Increase W-4 withholding. File a new W-4 with your employer requesting additional withholding per paycheck to offset the anticipated shortfall.
  • Make quarterly estimated tax payments (Form 1040-ES). Pay estimated taxes in the quarter when RSUs vest to avoid underpayment penalties.
  • Sell additional shares at vesting. If your plan allows, sell more than the minimum sell-to-cover amount to set aside cash for the tax shortfall.
  • Year-end tax projection. Run a tax projection in Q3 or Q4 to calculate the expected shortfall and adjust withholding or estimated payments accordingly.
  • State tax planning. Don't forget state taxes — states like California (up to 13.3%), New York, New Jersey, and Oregon have high marginal rates that compound the problem.

8. When to Use It

  • You early-exercise stock options at a startup when the stock value is very low (e.g., at or near the strike price).
  • The current FMV is low and you expect significant appreciation.
  • You want to start the LTCG holding clock immediately.

9. How to File

  • Exercise your options (pay the strike price for unvested shares).
  • Complete IRS Form 83(b) — there is no official IRS form; you prepare a letter/statement with required information.
  • Mail to the IRS within 30 days of the exercise/transfer date. This deadline is absolute — there are no extensions or exceptions.
  • Send via certified mail with return receipt for proof of timely filing.
  • Provide a copy to your employer.
  • Attach a copy to your tax return for the year of the election.

10. Required Information in the 83(b) Letter

  • Your name, address, and Social Security number
  • Description of the property (number of shares, company name)
  • Date of transfer
  • Nature of the restriction (vesting schedule)
  • FMV at time of transfer
  • Amount paid for the property
  • Statement that you are making the election under IRC Section 83(b)

11. Risks and Downsides

  • If the stock becomes worthless: You paid exercise cost and taxes for nothing. You cannot recover the taxes paid under the 83(b) election. You may be able to claim a capital loss, but it is limited.
  • If you leave before fully vesting: You forfeit unvested shares back to the company. You already paid tax on them. No refund of taxes paid. You can only claim a capital loss if you paid more than $0.
  • Liquidity risk: You have spent cash (exercise price + taxes) on illiquid private stock that may not have a market for years.
  • The 30-day deadline is absolute. Miss it and the election is invalid. There is no relief, no extension, no exception.
  • Cash outlay required. You must have the cash to pay the exercise price AND the taxes due.

12. When NOT to File 83(b)

  • Stock is already fully vested (no benefit).
  • FMV is already high (you'd owe significant tax on the current value).
  • You cannot afford to lose the exercise cost + taxes if stock fails.
  • RSUs (83(b) does not apply to RSUs since you don't receive property until vesting).

Common Mistakes

  • Not understanding that RSU vesting is a taxable event
  • Incorrect cost basis on tax return
  • Under-withholding surprise
  • Missing the 83(b) election deadline
  • Exercising ISOs without AMT analysis

Pro Tips

  • Run tax projections before vesting events
  • Use specific lot identification
  • Bunch charitable giving with equity events
  • Max out your ESPP
  • Negotiate extended exercise windows

Sources

Related Checklists