IRS Form W-9 vs. Substitute Form W-9: What’s The Difference?

The main difference between an IRS Form W-9 and a substitute Form W-9 is the format and how the information is collected. The official Form W-9 is a standardized document issued by the IRS, while a substitute Form W-9 is a customized version that businesses can incorporate into their onboarding, account opening, or tax documentation processes.

Both forms serve the same purpose: collecting taxpayer identification information and required certifications from U.S. persons. To be acceptable, a substitute Form W-9 must contain substantially similar information to the official IRS form and meet the applicable certification requirements.

Key takeaway: Businesses can use substitute Forms W-9 to streamline tax documentation collection, provided they comply with IRS requirements.

When Is a Form W-9 Required?

Use the Form W-9, Request for Taxpayer Identification Number and Certification, when you need to request the Taxpayer Identification Number (TIN) of a U.S. person. If you, as a Form W-9 requester, must file an information return with the IRS, you need to acquire the correct TIN to report the amount paid to the individual or any other reportable amount, which may involve backup withholding.

Who Needs to Complete Form W-9?

The Form W-9 is used to document U.S. persons, including but not limited to:

• An individual who is a U.S. citizen or U.S. resident alien;
• A partnership, corporation, company, or association created or organized in the United States or under the laws of the United States;
• Any estate (other than a foreign estate); or
• A domestic trust (as defined in Regulations section 301.7701-7).

In the case of disregarded non-U.S. entities, it is crucial to note that a Form W-9 may be necessary if there is a U.S. owner. The Form W-9 serves to gather the TIN and certification from U.S. persons. Encompassing both individuals and entities with U.S. ownership interest in disregarded non-U.S. entities. This ensures compliance with tax reporting requirements and allows for the proper documentation of U.S. owners for tax purposes.

Information Requested on a Form W-9

Forms W-9 request basic identity information, including the name of the individual or business on Line 1, the federal tax classification of the payee identified on Line 1 (e.g., sole proprietor, partnership, LLC, corporation), exempt payee and FATCA reporting codes, if applicable, address information, and TIN.

Can Businesses Use Substitute Forms W-9 Instead of IRS Forms?

A withholding agent may develop and use their own Form W-9, or a substitute Form W-9. In order to do this, the content must be substantially similar to the official IRS Form W-9. And it must satisfy certain certification requirements. This is beneficial for some organizations who wish to incorporate a substitution Form W-9 into other business forms or information requests. However it is important that the certifications on the substitute Form W-9 clearly state that under penalties of perjury:

• The payee’s TIN is correct,
• The payee is not subject to backup withholding due to failure to report interest and dividend income,
• The payee is a U.S. person, and
• The FATCA code entered on this form (if any) indicating that the payee is exempt from FATCA reporting is correct.

When providing substitute Forms W-9, you may not:

• Use a substitute Form W-9 that requires the payee, by signing, to agree to provisions unrelated to the required certifications, or
• Imply that a payee may be subject to backup withholding unless the payee agrees to provisions on the substitute form that are unrelated to the required certifications.

What Are the Signature Requirements for a Substitute Form W-9?

A substitute Form W-9 with a separate signature line exclusively designated for certifications meets the requirement for clear certification statements. However, if a single signature line is used for both required certifications and other provisions, the certifications must be highlighted. Achieve this emphasis by employing methods like highlighting, boxing, bold-face type, or presenting the language in a way that distinguishes it from all other information on the substitute form. Furthermore, the following statement must be prominently displayed, adhering to the same emphasis criteria mentioned above. It must appear immediately above the single signature line:

“The Internal Revenue Service does not require your consent to any provision of this document other than the certifications required to avoid backup withholding.”

Can Substitute Forms W-9 Be Collected Electronically?

With the allowance of substitute Forms W-9, we must talk to the electronic submissions of Forms W-9.

Requesters of Forms W-9 may establish a system for payees and payees’ agents to submit Forms W-9 electronically. This can include things like fax, or cloud-based applications like Comply Exchange’s eForms application. With electronic submissions, the system must:

• Ensure the information received is the information sent, and document all occasions of user access that result in the submission;
• Make reasonably certain that the person accessing the system and submitting the form is the person identified on Form W-9;
• Provide the same information as the paper Form W-9;
• Be able to supply a hard copy of the electronic Form W-9 if the Internal Revenue Service requests it; and
• Require as the final entry in the submission an electronic signature by the payee whose name is on Form W-9 that authenticates and verifies the submission. The electronic signature must be under penalties of perjury and the perjury statement must contain the language of the paper Form W-9.

Comply Exchange’s electronic substitute Form W-9 submission process is an automated and valid means for electronically collecting Forms. With integrations, guidance and validations in place, eForms can take the burden out of manually solicitating for and validating tax documentation.

In Conclusion

In conclusion, understanding the difference between the IRS Form W-9 and a substitute Form W-9 is important if you are considering including the request as part of other account opening or onboarding or AML/KYC processes. If you do not follow the rules for collecting substitute Forms W-9. Then you run the risk of having incorrect or invalid documentation on file.

If you are under an IRS audit, the tax documentation on file will serve as your first layer of defense. Especially when it comes to documenting the status of your U.S. payees. Along with any withholding and reporting that you may be required to do.  Not collecting TINs and reporting on U.S. payees, when required, can result in information reporting and withholding penalties. For more information on penalties, refer to a recent article on how Electronic Form Collection Can Reduce Withholding & Reporting Penalties.

Be sure to follow us on LinkedIn. And subscribe to the Comply Connect our monthly news round up!

Frequently Asked Questions About Substitute Forms W-9

Article Updated: October 2026