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Form 945X: Adjusted Annual Return of Withheld Federal Income Tax or Claim for Refund
IRS Form 945-X is the Adjusted Annual Return of Withheld Federal Income Tax or Claim for Refund, used to correct administrative errors on a previously filed Form 945. If underreporting tax, it must be filed by January 31 of the following year.
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IRS Form 945X - Adjusted Annual Return of Withheld Federal Income Tax or Claim for Refund
IRS Form 945-X is the Adjusted Annual Return of Withheld Federal Income Tax or Claim for Refund, used to correct administrative errors on a previously filed Form 945. If underreporting tax, it must be filed by January 31 of the following year.
Risk Radar
Scan points- 1Failure to attach an amended Form 945-A when filing late for underreported tax may result in an 'averaged' FTD penalty.
- 2Filing without entering the correct calendar year being corrected (YYYY).
- 3Not providing a detailed explanation of the grounds and facts supporting the correction in Part 3, line 7.
- 4Failing to pay the amount shown on line 5 by the time Form 945-X is filed when underreporting tax.
- 5Omitting the date the errors were discovered from the required entry field on page 1.
Plain English
This form allows you to fix mistakes made when you originally reported how much federal income tax was withheld from payees using Form 945. You use it either to adjust the amount you reported or to formally claim a refund for overpayments. If you are correcting an underreported amount, filing by the deadline is crucial to avoid penalties.
Submission Date
- Filing date: 2025-02-28 22:10:36
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
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Glossary Terms
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What this form is for
- Use this form when correcting administrative errors on a previously filed Form 945, meaning the reported federal income tax (including backup withholding) is not the amount actually withheld from payees.
- Do not use Form 945-X if you need to file for one or more years for which you should have filed Form 945; in that case, file Form 945 instead.
- Check Form CT-1 X, Form 941-X, Form 943-X, or Form 944-X instead when correcting those specific forms.
Form selector
Use this form or another form?
Underreported tax and making a payment
The correction is an underreport, and the filer must pay additional tax by filing.
✓ Verify that the amount on line 5 is positive.
Overreported tax and requesting refund/abatement
The filer overreported tax and wishes to claim a credit or reduction in liability.
✓ Confirm the appropriate box selection matches the goal.
Deadline or filing window
For correcting underreported tax, the due date is January 31 of the following year (the return period in which the error was discovered). If filed after this date, it must be properly postmarked or sent by the deadline to be treated as timely. No specific extension mechanism is detailed for Form 945-X itself; timeliness relies on meeting the filing window.
Checklist
What you need before filling it out
Underreported tax amount
The actual difference between reported and withheld amounts · Line 1/Form 945-X
Overreported tax amount
The actual difference between reported and withheld amounts · Line 2/Form 945-X
Explanation of grounds (Line 7)
Detailed explanation supporting the correction · Line 7/Form 945-X
Payment Amount Owed
The positive number shown on line 5 · Line 5/Form 945-X
Discovery Date
The date the filer discovered the error · Field noted (Implied)
Before you submit
- 1Ensure a detailed explanation is provided on line 7 for each correction shown.
- 2Confirm whether you are using the adjustment process (underreported/paying) or the claim process (overreported/requesting).
- 3Verify that if the amount owed on line 5 is positive, payment will be made by the time Form 945-X is filed.
- 4If filing a claim for refund/abatement and your credit is less than $1, ensure you ask IRS in writing to receive the refund or apply it.
- 5For payments, confirm the method chosen (EFTPS, Direct Pay, Card, Check/MO).
- 6If paying by check or money order, write the EIN, "Form 945-X," and the year corrected on the payment.
- 7Ensure a separate Form 945-X is filed for each distinct Form 945 being corrected.
How to file this form
- 1Complete all necessary fields on Form 945-X, ensuring Line 7 provides a detailed explanation of the correction grounds.
- 2Determine if you are using the adjustment process (underreported) or the claim process (overreported) and check the corresponding box.
- 3If underreporting tax, ensure the amount owed on line 5 is paid by the time Form 945-X is filed, using a valid payment method.
- 4File Form 945-X separately from the original Form 945 that is being corrected.
- 5Keep a copy of the completed and signed Form 945-X for your records.
- 6If paying by check or money order, ensure it is made payable to "United States Treasury" and clearly marked with your EIN, "Form 945-X," and the year corrected.
Known limitations
- 1The purpose of Form 945-X is to correct administrative errors only on a previously filed Form 945.
- 2If an underreported amount relates to an issue raised in an examination of a prior period, the correction may not be eligible for interest-free treatment.
- 3A correction will not be eligible for interest-free treatment if the filer knowingly underreported their tax liability or received a notice and demand for payment.
- 4If filing to correct overreported amounts within the last 90 days of a period of limitations, the claim process must be used instead of the adjustment process.
Field map
Compact field-by-field guide
Employer Info
1 items
Full legal name and Employer Identification Number.
Quarter
1 items
Select the calendar quarter this return covers.
Wages
1 items
Sum of all wages, tips, and other compensation paid to employees during the quarter.
Withholding
1 items
Total federal income tax withheld from employee paychecks.
SS & Medicare
1 items
Wages subject to Social Security tax (capped) and Medicare tax (uncapped).
Deposit
1 items
Indicate your deposit schedule: monthly, semiweekly, or next-day rule if over $100k.
Signatures
1 items
Must be signed by an authorized officer or agent of the employer.
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Fillable formOpen in Editor->The current edition is February 2025 (Rev.). Readers should check IRS.gov/Form945X for the latest information regarding developments related to Form 945-X and its instructions.
What changed or needs a fresh check
- Edition date — confirm it reads February 2025
- Form number — confirm it is Form 945-X
- Signature — must be provided (implied, as it's a return)
- Payment instructions — verify payment due by filing date (Line 5)
Quick Facts
Downloads
After you file
- 1Retain records related to Form 945-X as long as their contents may become material in the administration of any Internal Revenue law.
- 2If a credit is claimed and the period of limitations on credit or refund will expire within 90 days, check the box on line 2 of Form 945-X.
- 3The IRS usually processes claims shortly after they are filed, and the agency will notify the filer if the claim is denied, accepted as filed, or selected to be examined.
- 4If filing for a credit, the amount shown on line 5, plus any applicable interest, will generally be refunded by the IRS unless the IRS corrects Form 945-X during processing or the filer owes other taxes, penalties, or interest.
Sources
- SRCInstructions p.1 — The purpose of Form 945-X is to correct administrative errors only on a previously filed Form 945.
- SRCInstructions p.1 — File Form 945-X when an administrative error is discovered on a previously filed Form 945.
- SRCInstructions p.1 — If any due date falls on a Saturday, Sunday, or legal holiday, you may file Form 945-X on the next business day.
- SRCInstructions p.2 — If overreported tax was found on January 22, 2027, filing must occur by April 15, 2027 (end of period of limitations) using the claim process.
- SRCInstructions p.3 — Generally, a correction is eligible for interest-free treatment if filed on time, payment is made by filing date, discovery date is entered, and grounds/facts are explained.
- SRCInstructions p.4 — Line 2 must be checked if there is a credit (negative amount on line 5) and the period of limitations expires within 90 days of filing Form 945-X.
Common confusion points
When should I file this form?
File Form 945-X when an administrative error is discovered on a previously filed Form 945.
→ Confirm the error occurred after filing Form 945.
What happens if my due date falls on a weekend or holiday?
If any due date falls on a Saturday, Sunday, or legal holiday, file Form 945-X on the next business day.
→ Check the calendar for the specific filing period's deadline.
When do I use the adjustment process versus the claim process?
Use the claim process if you are correcting overreported amounts in the last 90 days of a period of limitations; otherwise, use the adjustment process (or both).
→ Review lines 2 and 5 to determine which process applies.
What makes my correction eligible for interest-free treatment?
Generally, filing on time, paying the amount shown on line 5 by the filing date, entering the discovery date, and explaining the grounds/facts support it.
→ Ensure all four conditions are met when submitting Form 945-X.
What happens if I overreported tax (a credit)?
The amount is entered as a negative number on line 5; check the box on line 2 to indicate this credit.
→ Verify that Line 5 shows a value less than zero, such as "-115.00".
What must be done if I am a paid preparer?
A paid preparer must sign Form 945-X and provide the required information in the Paid Preparer Use Only section of Part 4.
→ Check Part 4 to ensure all preparer details are complete.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- A second Form 945-X must be filed to correct overreported amounts when using the claim process.
Questions about IRS Form 945X
What is IRS Form 945X used for?
This form allows you to fix mistakes made when you originally reported how much federal income tax was withheld from payees using Form 945. You use it either to adjust the amount you reported or to formally claim a refund for overpayments. If you are correcting an underreported amount, filing by the deadline is crucial to avoid penalties.
Who must file IRS Form 945X?
The filer category that must file IRS Form 945-X is generally any entity that filed a Form 945 and discovered an administrative error in its reported federal income tax (including backup withholding).
What information does IRS Form 945X require?
The form collects information such as the Employer Identification Number (EIN), Name, and Address on page 1, and details corrections within Part 3. Specifics are provided by entering the calendar year being corrected and detailing the grounds for correction.
When is IRS Form 945X due?
If correcting underreported tax, Form 945-X must be filed by the due date of the return for the period in which the error was discovered (which is January 31 of the following year).
Where do I file IRS Form 945X?
The form can be sent to the IRS via USPS or an IRS-designated private delivery service (PDS). If it arrives after the due date, it must be properly addressed and postmarked/sent by the deadline.
How do I complete IRS Form 945X?
The filer must complete both pages of IRS Form 945-X, entering their EIN and name on all parts. Corrections are detailed in Part 3, followed by a declaration under penalty of perjury in Part 4. The entire form must be signed to finalize the submission.
What happens if IRS Form 945X is filed incorrectly?
Failure to file Form 945-X on time when underreporting tax generally means the correction may not be interest free or subject to failure-to-pay (FTP) or failure-to-deposit (FTD) penalties.
When should I file this form?
File Form 945-X when an administrative error is discovered on a previously filed Form 945. Confirm the error occurred after filing Form 945.
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