Glossary

Form W-9

Form W-9 is the request for taxpayer identification number that businesses collect from U.S. contractors and payees before issuing 1099 forms, and that brokers and crypto exchanges collect before reporting on Form 1099-DA.

How it works

Form W-9 certifies a U.S. person’s taxpayer identification number and that they are not subject to backup withholding. Businesses collect it before issuing 1099 forms; brokers and crypto exchanges collect it before reporting on Form 1099-DA. Refusing to provide it triggers 24 percent backup withholding on reportable payments.

Why it matters

The W-9 is how an exchange links your account to your Social Security number, which is what makes 1099-DA matching possible.

Related: Form 1099-DA, KYC.

Guides that cover form W-9

Related terms

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Where this comes up in our work

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Definitions are general information, not legal advice, and may not reflect the most recent changes in law.

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