In plain terms
How the tax works
income is reported as wages on your .
The same shares' sale is reported on the , frequently with $0 or missing basis.
If you do not adjust basis, the sale's gain includes value already taxed as wages.
The result feels like double taxation, but it is really one missing adjustment.
What to check on your end
- Whether the amount is in your wages.
- The basis the reported for the sale.
- Your records for the correct basis.
- Whether software imported $0 basis and computed a large gain.
- That, after adjustment, the gain reflects only the price change since .
Common mistake
Example scenario (hypothetical)
Illustration only, not your tax situation.
When a CPA is worth it
- You already filed before noticing the issue.
- Totals do not reconcile after adjusting basis.
- You have many lots and partial sales.
- You received corrected forms.
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.
How RSU vest wages and share sales appear on W-2, 1099-B, and Form 8949.
- 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.
- Instructions for Form 8949 — Sales and Other Dispositions of Capital Assets
Internal Revenue Service · Official
How to report sales when broker-reported basis is incorrect, including adjustment codes.
- 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.
Related calculators
Related pages
- Why Is My RSU Cost Basis Zero?
Zero basis on 1099-B usually means the broker did not link your vest wage income — not that tax was skipped.
- How to Adjust RSU Cost Basis
Basis adjustments connect vest wage income to later sales — document FMV from vest records.
- 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.
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.
