What Documentation Proves Tax Work Was Completed

Why documentation matters

If you paid someone to handle your taxes—prepare a return, file paperwork with the IRS, resolve a compliance issue, or represent you in an audit—you need documentation proving that work was actually completed. Without documentation, you have no proof that the professional did what they said they would do, and the IRS will not recognize your claim of reliance on professional advice.

Documentation serves two purposes: First, it gives you proof of the work completed so you can verify what was done. Second, if the IRS later questions whether a return was filed or work was completed, you have evidence to support your position. Without documentation, you are relying entirely on the word of the professional—which may not be reliable if they've disappeared or refuse to respond.

What does NOT prove a return was filed

Many documents seem like proof but actually aren't:

Email saying "I'll file your return" — Promises are not proof of filing. The email must confirm actual filing, not just intent.
A prepared tax return PDF — A return sitting on a computer drive is not filed. Filing means it was electronically submitted to or physically mailed to the IRS.
An invoice or receipt for tax preparation services — Invoices prove you paid for a service, not that the service was completed or the return was actually filed.
A signed engagement letter — An engagement letter establishes the relationship and scope of work, but it doesn't prove the work was completed.
Your own copy of the filed return — Having a copy doesn't prove it was filed with the IRS. Many people have unsigned copies of returns that were never filed.
A verbal agreement or phone conversation — Without documentation, the IRS will not recognize an oral agreement. You need written proof.
A bank statement showing payment to the tax professional — Payment proves you hired someone, but it doesn't prove they filed anything.

The IRS's standard is clear: If you cannot produce a document showing the IRS accepted the filing, the IRS will not consider the return filed, even if a professional says they filed it.

What DOES prove a return was filed

Valid proof that a return was filed includes:

IRS Filing Acceptance Notice (Form 1040/1120 acceptance receipt) — This is the primary proof of electronic filing. The IRS generates this automatically when a return is accepted electronically.
IRS Tax Transcript showing the return on file — An account or tax return transcript shows what the IRS has on record for your account, including returns filed.
Form 2848 (Power of Attorney) filed with the IRS — If a tax professional filed a Form 2848 with the IRS to represent you, the IRS has a record of their representation.
Confirmation email from e-filing provider — If your return was e-filed through an IRS-approved software provider, the provider should send a confirmation of acceptance.
IRS Correspondence referencing the return — Any IRS notice (audit notice, CP-2000, etc.) that references a specific return on file proves that return was accepted by the IRS.
Postmarked certified mail receipt (for paper returns) — If a return was mailed to the IRS, a certified mail receipt with the IRS receipt date stamp provides proof of filing.
IRS stamped received copy (for paper returns) — If you hand-delivered or mailed a return and received a stamped copy back showing it was received by the IRS, that's proof of filing.

IRS Filing Acceptance Notice (Form 1040/1120 filing confirmation)

When a return is filed electronically, the IRS generates a Filing Acceptance Notice. This document confirms:

The return was received and accepted by the IRS
The date it was accepted
The IRS Submission ID (a unique identifier for that filing)
The tax year and type of return
The taxpayer identification number and name

This is the gold standard of proof. If the professional who filed your return did not provide you with this document, they should. If they refuse to provide it, that's a red flag—it suggests the return may not have been filed.

Tax transcripts as proof of filing

An IRS Tax Transcript or Account Transcript shows what the IRS has on file for you. If a return was filed and accepted by the IRS, it will show on your transcript. You can request a transcript by calling the IRS at 1-800-908-9946 or by going online to IRS.gov.

If a professional claims they filed a return but the return doesn't appear on your transcript, the return was not filed. This is definitive evidence that the work was not completed. Conversely, if the transcript shows the return on file, the IRS has record of it being filed.

Acceptance receipts and confirmation emails

If your return was e-filed, the tax preparation software (provided by the professional or a third-party service) should have sent a confirmation email when the return was accepted by the IRS. This email typically includes:

Confirmation that the return was successfully transmitted to the IRS
The submission ID
The date the IRS accepted it
The tax year and return type

If the professional never sent you a confirmation email and cannot produce one, this is another red flag. Legitimate e-filing services provide automatic confirmation to both the preparer and the taxpayer.

Power of Attorney (Form 2848) and engagement letters

A Form 2848 (Power of Attorney and Declaration of Representative) filed with the IRS proves that a professional has been authorized to represent you before the IRS. This is filed separately from your return and shows the IRS that a specific person or firm is acting on your behalf.

An engagement letter from the professional outlines the scope of work they agreed to perform. While not proof that the work was completed, it establishes what they were supposed to do. Combined with other documentation (like filing acceptance notices or transcripts), an engagement letter helps demonstrate the professional's obligation to complete the work.

What to do if you can't find proof

If you hired someone to file a return and you can't find documentation proving it was filed:

Contact the professional who prepared it: Request a copy of the filing acceptance notice, submission ID, or any documentation proving the return was filed. If they say they don't have it, ask them to provide the IRS with a copy.
Request your tax transcript: Order a tax transcript from the IRS to see what they have on file. If the return appears on your transcript, it was filed. If it doesn't appear, the work was not completed.
Contact the IRS directly: Call the IRS at 1-800-908-9946 and ask if a return for the specific year in question is on file. The IRS can tell you if they received and processed the return.
File the return yourself (if not filed): If the professional didn't file it, you still can. The IRS prefers late filing to no filing. Filing late incurs penalties and interest, but it's better than allowing the account to remain unfiled.
Consider pursuing the professional: If a professional took your money and didn't file the return, you may have grounds for a complaint to their licensing board, small claims court action, or referral to law enforcement.