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    IRS Form 3921

    Form 3921: Exercise of an Incentive Stock Option Under Section 422(b)

    Report the exercise of incentive stock options by employees.

    Filing Deadline

    January 31 (to employee) / February 28 (paper) or March 31 (e-file) to IRS

    Purpose

    Track ISO exercises for AMT and tax reporting

    AMT Impact

    ISO exercises may trigger Alternative Minimum Tax

    Overview

    Form 3921 is issued by corporations when an employee exercises an incentive stock option (ISO) granted under an IRC Section 422(b) plan. The form provides information needed for the employee to properly report the exercise and any subsequent sale.

    ISOs receive favorable tax treatment if holding period requirements are met, but the exercise spread may be subject to Alternative Minimum Tax (AMT).

    Who Must File

    Required Filers

    • Corporations that grant incentive stock options
    • Must file for each ISO exercise during the calendar year
    • Required even if employee hasn't sold the shares
    • Applies to options granted under Section 422(b) plans

    Form Structure & Instructions

    Here's what information is required in each section:

    Grant Information

    Details about the ISO grant

    Box 1
    Date Option Granted
    Original date ISO was granted to employee
    Box 2
    Date Option Exercised
    Date employee exercised the option
    Box 3
    Exercise Price per Share
    Price paid per share when exercising
    Box 4
    FMV per Share on Exercise Date
    Fair market value per share on exercise date

    Share Details

    Number of shares and identifying information

    Box 5
    Number of Shares Transferred
    Number of shares acquired through exercise
    Box 6
    Date Legal Title Transferred
    Date ownership transferred to employee
    Box 7
    Transferor Employer ID
    EIN of corporation transferring the stock

    Important Filing Notes

    Alternative Minimum Tax (AMT)

    The spread between FMV (Box 4) and exercise price (Box 3) is a preference item for AMT. You may owe AMT in the year of exercise even with no cash sale.

    Holding Period Requirements

    For favorable tax treatment, must hold shares at least 2 years from grant date and 1 year from exercise date. If met, all gain is capital gain with no ordinary income.

    Disqualifying Disposition

    Selling before holding period requirements are met triggers ordinary income equal to lesser of (1) gain on sale or (2) spread at exercise. Employer may report on W-2.

    Basis Adjustment for AMT

    If you paid AMT, your basis for regular tax purposes may differ from AMT basis. Track both for future sale calculations and potential AMT credit.

    ISO Exercise Reporting Excellence

    Ensure accurate Form 3921 reporting for employee stock option exercises. We handle the compliance complexity for your equity compensation plans.

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