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1099-B RSU Adjustment Helper

Structured helper for RSU 1099-B problems. zero basis, duplicate wage reporting, and supplemental plan lot details.

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Most problems come down to one fix: the form shows $0 or missing , so your gain looks far too big. Your basis is usually the value already taxed as wages. Adjusting basis, not deleting forms, is what removes the apparent double tax.

Planning estimate

This is a workflow helper to spot why your 1099-B might look wrong, not a tax-filing engine. It does not tell you which form line to use. Confirm any adjustment with your tax software or a tax professional.

We do not pre-fill personal financial values. Estimates appear only after you enter your own numbers.

Enter your details to estimate

Add your equity, income, state, and withholding details to see an educational estimate. No personal financial values are pre-filled.

Start with the fields below.

Your details

Enter your own numbers below. This is an estimate, not a filing position.

RSU vest value is usually included in W-2 Box 1 wages.

Required to estimate

Fair market value when the shares vested, usually the correct basis.

$

Required to estimate

Often $0 for RSUs. Enter the total basis your broker reported, or leave blank for $0.

$

Gross proceeds reported on your 1099-B for this sale.

$

Required to estimate

Brokers often provide a supplemental statement with the adjusted basis.

Results will appear here once you enter the required details on the left.

Related guides

Why this happens

Brokers often do not know your wage income, so they report $0 or blank basis on sales.

Without an adjustment, software treats the whole sale as gain, double-counting income already on your .

Your correct basis is generally the at .

A supplemental stock plan statement usually lists the price you need.

What to check

  • The basis reported on each sale.
  • Your records or supplemental statement for the true basis.
  • Whether the income already appears on your .
  • Whether your software supports a basis adjustment field.
  • Short- vs long-term classification for each lot.

Common mistake

Deleting a form to remove a 'duplicate.' The right fix is a cost-basis adjustment that ties the sale back to the value, not removing income you actually have.

Example scenario (hypothetical)

Illustration only, not your tax situation.

Example: a shows a $9,000 sale with $0 basis. The shares vested at $8,800, which is already in wages. Adjusting basis to $8,800 leaves about $200 of gain instead of $9,000.

When to get help from a tax pro

  • Totals do not reconcile after adjusting basis.
  • You sold many lots with different prices.
  • You already filed before noticing the issue.
  • You received corrected forms.

Related calculators

Related pages

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.