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Official form guide
Form 12661: Disputed Issue Verification
Department of the Treasury - Internal Revenue Service Form 12661 is a Disputed Issue Verification form used by taxpayers to disagree with audit results; it has catalog number 29360J.
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IRS Form 12661 - Disputed Issue Verification
Department of the Treasury - Internal Revenue Service Form 12661 is a Disputed Issue Verification form used by taxpayers to disagree with audit results; it has catalog number 29360J.
Risk Radar
Scan points- 1Do not send original documents; photocopies of all supporting information must be submitted with Form 12661.
- 2Filing without completing a separate block for every disputed issue or adjustment.
- 3Sending original documents instead of required photocopies only.
- 4Forgetting to number the supporting information correctly according to its disputed issue.
- 5Not listing the 'Reason why you disagree with the audit results' for each item.
Plain English
This form allows a taxpayer to formally tell the IRS which specific parts of an audit they do not agree with. By using Form 12661, the filer documents why they disagree and provides proof for their claim. This helps resolve disagreements about how income or deductions were treated.
Submission Date
- Filing date: 2016-06-21 00:00:00
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
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What this form is for
- Use this form when disagreeing with an audit result or adjustment made by the Internal Revenue Service.
- Do not use Form 12661 when you are submitting documentation without a specific issue or adjustment to dispute, as blocks must be completed for each item.
- Check no other specific form number instead when disputing issues; this source only references itself.
Form selector
Use this form or another form?
Disputing an adjustment related to business income
The reason for disagreement must be detailed in the 'Reason why you disagree' field.
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Responding to a specific IRS Notice of Deficiency
Ensure each block corresponds directly to an issue mentioned in the notice received.
✓ Check before you continue
Disputing an adjustment on a corporate return
The 'Amount claimed on original return' must match the amount shown on your filed return.
✓ Check before you continue
Deadline or filing window
The official source does not state a specific deadline for filing IRS Form 12661. However, the form is used to address issues found during an audit review period. No extension mechanism is detailed in this excerpt.
Checklist
What you need before filling it out
Disputed issue or adjustment
The specific item being contested · Block header (e.g., Section 1)
Reason why you disagree with the audit results
A detailed explanation of the disagreement · Block field under 'Reason why you disagree'
Amount claimed on original return
The dollar amount from your initial tax filing · Block field under 'Amount claimed on original return'
Amounts allowed on Audit report
The dollar amount determined by the IRS during audit · Block field under 'Amounts allowed on Audit report'
Supporting information
Photocopies of documents supporting the claim/dispute · Attached to the form, corresponding to block number
Before you submit
- 1Complete a separate block for each issue or adjustment with which disagreement exists.
- 2Attach photocopies of supporting information for every disputed issue or adjustment listed on Form 12661.
- 3Number the attached supporting information using the same number as its corresponding disputed issue or adjustment.
- 4Ensure that if additional blocks are needed, they are photocopied and numbered accordingly.
- 5Fill in the Taxpayer name and Tax period fields at the top of Form 12661.
- 6Enter the Social Security Number on Form 12661.
- 7Do not send original documents; confirm that only photocopies are being sent.
How to file this form
- 1Complete a separate block for each disputed issue or adjustment on Form 12661 (Catalog Number 29360J).
- 2For each block, detail the 'Disputed issue or adjustment', provide the 'Reason why you disagree with the audit results', and list both the 'Amount claimed on original return' and the 'Amounts allowed on Audit report'.
- 3Attach photocopies of all supporting information for each disputed item, ensuring these documents are numbered to match their corresponding block number.
- 4Send the completed Form 12661 along with the attached photocopied evidence to the IRS.
Known limitations
- 1A separate block must be completed for every issue or adjustment with which the taxpayer disagrees.
- 2Photocopies of supporting information must be attached and numbered to match the disputed issue number.
- 3Original documents should not be sent; only photocopies are to be submitted.
Field map
Compact field-by-field guide
General Info
2 items
Full legal name and taxpayer identification number (SSN or EIN).
Current mailing address.
Details
2 items
Complete all applicable sections of this form according to the official IRS instructions.
Enter the relevant dollar amount if this form involves tax calculation.
Certification
1 items
Read and acknowledge any certifications required by this form.
Signatures
1 items
Sign and date. Unsigned forms cannot be processed.
Almost done reviewing the fields?
Fillable formOpen in Editor->The current edition of IRS Form 12661 is Revision 10-2015, dated October 2015; the source does not point to a separate page indicating newer revisions.
What changed or needs a fresh check
- Edition date — confirm it reads October 2015.
- Catalog Number — confirm it is 29360J.
- Mailing address — Not stated in the official source.
- Signature — Confirm a signature line exists (implied by instructions, though not explicitly listed on p.1).
- Form revision number — confirm it reads Rev. 10-2015.
Quick Facts
Downloads
After you file
- 1The taxpayer must keep a copy of the completed Form 12661.
- 2Supporting information attached to Form 12661 must also be kept by the taxpayer.
- 3Photocopies of supporting information must be numbered corresponding to the disputed issue number on Form 12661.
- 4The Privacy Act Notice instructions for the specific return should be reviewed.
Sources
- SRCCatalog Number 29360J is listed for Form 12661.
- SRCThe form revision date on file is October 2015 (Rev. 10-2015).
- SRCTaxpayers must complete a separate block for each issue or adjustment with which they disagree (Instructions p.1).
- SRCSupporting information photocopies must be numbered the same as its disputed issue (Instructions p.1).
- SRCThe form requires fields for 'Amount claimed on original return' and 'Amounts allowed on Audit report' for each dispute block (Form p.1).
- SRCOnly photocopies of supporting documents should be sent, not originals (Form p.1).
Common confusion points
What if I have more than three issues or adjustments to dispute?
The source only shows blocks for 1, 2, and 3.
→ Photocopy additional sheets and number them accordingly.
Do I send the original documents when filing Form 12661?
No, the instructions specify sending photocopies only.
→ Ensure every document sent is a copy, not an original.
How do the supporting documents relate to the issues on Form 12661?
The supporting information must be numbered with the same number as its disputed issue.
→ Check that Document #3 supports Issue #3.
What if I disagree with multiple adjustments within one tax period?
Complete a separate block for each specific issue or adjustment.
→ Do not try to list all disagreements on a single line item.
Where do the amounts come from when filling out Form 12661?
The form requires 'Amount claimed on original return' and 'Amounts allowed on Audit report'.
→ Verify these figures against your initial filing and the audit notice.
What is the revision date to check on my copy of Form 12661?
The edition filed is October 2015 (Rev. 10-2015).
→ Confirm this date matches the form you are using.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- The instructions mention a Privacy Act Notice, which relates to disclosures made during the audit process.
Questions about IRS Form 12661
What is IRS Form 12661 used for?
This form allows a taxpayer to formally tell the IRS which specific parts of an audit they do not agree with. By using Form 12661, the filer documents why they disagree and provides proof for their claim. This helps resolve disagreements about how income or deductions were treated.
Who must file IRS Form 12661?
A taxpayer must file IRS Form 12661 when they wish to dispute an issue or adjustment found during an audit review.
What information does IRS Form 12661 require?
The form collects details such as the Taxpayer name, the Social Security Number, and specific information for each disputed item. It requires recording the 'Disputed issue or adjustment,' the 'Reason why you disagree with the audit results,' and the amounts claimed versus allowed on the original return and audit report.
Where do I file IRS Form 12661?
The instructions state that taxpayers must send photocopies only of supporting documentation. The routing location is not specified beyond the general requirement to submit the form for review.
How do I complete IRS Form 12661?
First, complete a separate block for every issue or adjustment being disputed. For each block, detail the 'Disputed issue or adjustment,' provide the reasoning, and list the amounts claimed versus allowed. Finally, sign the form before sending it to ensure proper filing.
What happens if IRS Form 12661 is filed incorrectly?
While no specific penalty is listed, submitting Form 12661 incorrectly means the IRS will receive inaccurate information regarding the taxpayer's disagreement with the audit results.
What if I have more than three issues or adjustments to dispute?
The source only shows blocks for 1, 2, and 3. Photocopy additional sheets and number them accordingly.
Do I send the original documents when filing Form 12661?
No, the instructions specify sending photocopies only. Ensure every document sent is a copy, not an original.
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