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Estimate vest tax

How do I fix RSU cost basis on my tax return?

Basis adjustments connect vest wage income to later sales. document FMV from vest records.

You know your 1099-B basis is wrong and tax software is computing a huge gain. This page is a filing-season walkthrough for adjusting RSU sales to vest FMV without deleting forms or double-counting W-2 income.

Start here

You generally report the sale on Form 8949 / Schedule D with an adjustment that sets basis to the already taxed as wages. Keep your confirmation and as support. Tax software has fields for basis adjustments; exact labels vary by product.

What you need before using this

  • for each sale.
  • per share for the lots sold.
  • showing wages in the year.
  • Tax software account or paper Form 8949 instructions open.

Software labels change by year. Follow your product's RSU or basis adjustment workflow and keep vest proof.

Why this happens

Brokers file with incomplete basis while the IRS also receives your wages.

You are responsible for reporting the correct gain even when forms disagree.

Form 8949 adjustment codes explain why your basis differs from the broker statement.

Without adjustment, you risk overpaying tax on income already taxed at .

What to check

  • × shares sold equals proposed basis.
  • includes wages in the correct tax year.
  • Proceeds on 8949 match after fees if applicable.
  • Holding period (short vs. long term) measured from .
  • Software adjustment code matches IRS instructions for incorrect broker basis.

Adjusting to a round number without records

Use the from your confirmation, not a guess. Audits and amended returns require tie-out between grant ID, PDF, wages, and the basis you report on Form 8949.

What to check in your documents

  • imported into software (note original $0 basis).
  • Form 8949 adjustment column after you enter .
  • Box 1 supporting wage amount.
  • confirmation PDF archived by grant and date.
  • Schedule D total gain reasonable vs. price change since .

Example scenario (hypothetical)

Illustration only, not your tax situation.

Dana sold 100 shares for $15,000 proceeds. confirmation shows $110/share basis ($11,000). The shows $0 basis. Dana reports $15,000 proceeds and $11,000 basis on Form 8949 with an adjustment explaining basis from employer wage income, and keeps the PDF with the tax file.

Questions people ask

Which Form 8949 box do RSU sales use?
Many plan sales are noncovered and short-term, but check Box 3 on your for holding period and Box 5 for covered/noncovered status. Your software usually routes the sale once you import the form.
Do I enter an adjustment code?
IRS instructions for Form 8949 describe codes when basis reported to the IRS is incorrect. Tax software often prompts for this when you change basis from the imported amount.
What if I already filed with $0 basis?
You may need to amend the return for that year. Gather records before amending so the corrected gain matches basis.
Can I skip Form 8949 if gain is small after adjustment?
Reporting rules depend on totals and software eligibility for summaries. Even small gains usually still require reporting the sale with correct basis.

When to get help from a tax pro

  • Multiple vests sold on one aggregated line.
  • Employer issued a corrected after you filed.
  • You transferred shares between brokers.
  • You are amending a prior-year return.

Related calculators

Related pages

Sources and notes

Form 8949 basis adjustments; TurboTax link is filing workflow only, not tax law.

Community and tax-software links describe filing steps, not tax law. Confirm rules against official sources or your advisor.

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.