vestingtax.com
RSU tax calculator

Why does my 1099-B show $0 cost basis on RSU shares?

Zero basis on 1099-B usually means the broker did not link your vest wage income — not that tax was skipped.

You imported your brokerage 1099-B into tax software and every RSU sale shows zero cost basis. This page explains why brokers do that and what you should use instead before you file.

In plain terms

Brokers often do not know your wage income, so they report zero or blank basis on sales, especially for noncovered securities. That does not mean your true basis is zero. Your basis is usually the at , which should already appear on your as .

Gather before you start

  • for each sale.
  • for the year.
  • confirmations with per share.
  • Broker supplemental stock plan statement if available.

Broker reporting varies by administrator. Always tie basis back to your vest records and W-2.

How the tax works

Your broker sees the sale, not the compensation event at handled by payroll.

Employer payroll and the brokerage account are separate systems.

Many sales are noncovered on , with weaker broker basis reporting obligations.

Tax software imports literally unless you override at filing time.

What to check on your end

  • Whether basis field is blank, zero, or a small incorrect number.
  • Noncovered security indicator on .
  • that matches wages.
  • Whether proceeds match your trade confirmation.
  • If multiple lots sold, whether each needs its own basis.

Filing with $0 basis because the form says so

That can overstate and make it look like you skipped tax at when wage tax may already have been paid. You usually need to adjust basis upward to and keep proof with your records.

What to pull from your files

  • Box 1e and Box 5 noncovered flag.
  • Box 1 wages including income.
  • confirmation: per share and share count.
  • Supplemental lot detail from broker (sometimes lists adjusted basis).
  • Form 8949 draft from software showing inflated gain before adjustment.

Example scenario (hypothetical)

Illustration only, not your tax situation.

Chris sells 80 shares from a March . The shows $12,000 proceeds and $0 basis. Chris's confirmation shows of $120 per share ($9,600 on the ). Correct gain is closer to $2,400, not $12,000, before fees.

Questions people ask

Is $0 basis ever correct for RSUs?
For typical vests taxed as wages at delivery, $0 broker basis is usually incomplete, not correct. Basis should reflect unless a different tax event applied.
Why is the sale marked noncovered?
IRS rules define when brokers must report basis on . Many equity plan sales are noncovered, which means you are responsible for reporting correct basis even when the form shows $0.
Will the IRS know if I leave basis at zero?
IRS matching sees proceeds. If gain looks too large relative to your wages, you may get a notice. Correct basis with documentation is the usual fix.
My broker sent a supplemental statement later — do I still adjust?
If the supplemental statement shows corrected basis that matches your records, use it. If it still shows $0, adjust manually and keep proof.

When a CPA is worth it

  • You sold many small lots across years.
  • wages do not match any confirmation.
  • You received an IRS notice about .
  • Shares were transferred from an employer plan to a retail account.

Sources and notes

Primary tax claims on this page are supported by the official and secondary sources below. Broker and software links describe reporting mechanics — confirm rules against IRS or state guidance.

Why brokers may report $0 basis on RSU sales and how vest FMV on W-2 relates.

Related calculators

Related pages

For learning, not filing

VestingTax.com is not a CPA firm or tax preparer. Grants, employers, and states all differ. Use the cited IRS and state sources above, your own documents, and a qualified tax professional before you make decisions from this guide.

Editorial standardsDisclaimer