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.
Start here
What you need before using this
- 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.
Why this happens
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
- 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
What to check in your documents
- 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.
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 to get help from a tax pro
- 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.
Related calculators
Related pages
- How to Adjust RSU Cost Basis
Basis adjustments connect vest wage income to later sales. document FMV from vest records.
- RSUs on 1099-B: What to Look For
1099-B for RSUs often shows low or zero basis. that does not mean your true basis is zero.
- Are RSUs Taxed Twice?
Vest income and later sales can both show up on tax forms. that is not always double tax on the same dollars.
Sources and notes
Why brokers may report $0 basis on RSU sales and how vest FMV on W-2 relates.
- About Form 1099-B — Proceeds from Broker and Barter Exchange Transactions
Internal Revenue Service · Official
Broker reporting of sales proceeds and basis; basis on 1099-B may be incomplete for equity-compensation shares.
- Filing taxes for restricted stock, RSUs, or performance awards (tax guide PDF)
Fidelity Stock Plan Services · Brokerage explainer
Explains W-2 vest income, 1099-B with $0 basis, supplemental adjusted cost basis, and Form 8949 reporting.
For learning, not filing
Grants, employers, and states all differ. Use your own documents and a qualified tax professional before you make decisions from this guide.
