When Does the Taxpayer Sign the Tax Return?

A signature on a tax return is a requirement for the document to be considered valid by the Internal Revenue Service (IRS). By signing, the taxpayer acknowledges they have reviewed the entire return and attests under penalty of perjury that the information is true, correct, and complete to the best of their knowledge and belief. This act transforms the collection of forms and figures into a legally binding submission.

Signing as the Final Review and Approval

The taxpayer’s signature should be the final action taken before the tax return is submitted to the government, and only after a comprehensive review of every entry. Affixing your signature signifies that you have examined all reported income, deductions, and credits and are formally approving the document’s contents.

The declaration printed directly above the signature line on Form 1040 explicitly states this responsibility. The phrase “Under penalties of perjury” carries significant legal weight, making a knowingly false statement a federal crime. Signing prematurely undermines this declaration and exposes the filer to potential consequences.

This principle holds regardless of whether you prepare the return yourself or use a paid professional. The responsibility for the return’s accuracy ultimately rests with the taxpayer whose name is on it. The signature is the final approval of the work before it is sent to the IRS.

Signature Procedures for E-Filing and Paper Filing

The method for signing a tax return differs based on whether it is filed electronically or on paper. For e-filed returns, taxpayers use a Personal Identification Number (PIN) as a digital signature. The Self-Select PIN method is for taxpayers who prepare their own return using tax software and requires creating a five-digit PIN and authenticating identity using the prior-year Adjusted Gross Income (AGI) or prior-year PIN.

When using a tax professional, the Practitioner PIN method is used. The taxpayer signs Form 8879, IRS e-file Signature Authorization, which grants the preparer permission to enter the taxpayer’s PIN on the electronic return. Signing Form 8879 confirms the taxpayer has reviewed the return and approves its submission.

Paper filers must provide a physical “wet signature” in ink in the designated block on Form 1040, along with the date. An unsigned paper return is considered invalid by the IRS and will be rejected, which delays processing and any potential refund.

Identifying Who Must Sign the Return

For an individual filing a single, head of household, or married filing separately return, only that individual needs to sign. When a married couple files a joint return, both spouses must sign for it to be valid. This rule reflects the concept of joint and several liability, where both individuals are equally responsible for the accuracy of the return and any tax owed.

If a taxpayer has passed away, a surviving spouse can sign a joint return and write “Filing as surviving spouse” in the signature area. If a court has appointed a personal representative, such as an executor, that representative must sign. An agent holding a valid power of attorney, documented on Form 2848, can also sign on a taxpayer’s behalf.

The Paid Preparer’s Signature Requirement

Any individual compensated for preparing a federal tax return must also sign it in the “Paid Preparer Use Only” section of Form 1040. They are required by law to include their signature and their Preparer Tax Identification Number (PTIN).

The preparer’s signature attests that the return is accurate based on the information the taxpayer provided. It does not, however, transfer the ultimate responsibility for the return’s accuracy from the taxpayer. For e-filed returns, the preparer signs the electronic record after the taxpayer has reviewed the return and signed Form 8879.