Generate Form 3921 for Every ISO Exercise in Minutes

Slice fills in IRS Form 3921 from the grant, exercise, and 409A data already in your cap table, then sends the filing report to your accountant on schedule.

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DIGITAL FORMS

Every Required Field, Filled In Automatically

Grant date, exercise date, exercise price, fair market value on the exercise date, and share count come straight from your Slice records. Slice flags any exercise that's missing data, such as an employee's TIN or address, before a form is generated.

Form 3921 filled in automatically from Slice grant, exercise and 409A data

Generate Form 3921 flow in Slice for all ISO exercises in a tax year

ONE FORM PER EXERCISE

Generate a Form for Every ISO Exercise in One Run

The IRS requires a separate Form 3921 for each ISO exercise. Slice generates every form for the tax year in a single run, ready to share with your employees and your filing provider, and alerts you ahead of each filing deadline.

ISO $100K LIMIT

Keep ISOs, NSOs, and Local Grants in the Right Buckets

Slice calculates the $100,000 ISO limit on every grant and moves the excess to NSO automatically, while non-US grants follow their own country's rules, so Form 3921 covers exactly the exercises it should.

Grant split between ISO and NSO under the $100K annual limit in Slice

FORM 3921 REPORT

Export Every Detail Your Accountant Needs

The Form 3921 report in Slice brings together every ISO exercise for the year with the grant, exercise, fair market value, and employee data needed to file. Export it to Excel in one click, or schedule it to reach your accountant every January.