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Part 21. Customer Account Services

Chapter 5. Account Resolution

Section 4. General Math Error Procedures

21.5.4  General Math Error Procedures

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21.5.4.1  (12-01-2007)
General Math Error Procedures Overview

  1. This section provides guidelines for adjusting math error cases and for initially identifying math errors. It includes the steps for processing math error cases and describes the taxpayer's rights when the Service processes returns pursuant to math error authority.

  2. See IRM 21.6.3, Credits, or IRM 21.6.1, Filing Status and Exemption Adjustments, for responses to math error notices concerning incorrect or invalid TINs listed by the taxpayer for:

    • Personal exemptions for the primary or secondary taxpayer

    • Dependents

    • Child and Dependent Care Credit

    • Earned Income Tax Credit (EIC)

    • Child Tax Credit

    • Lifetime Learning Credit, Form 8863

    • HOPE Credit, Form 8863

    Note:

    Use credit reference number (CRN) 764/765 when an EIC adjustment is required.

  3. In math or clerical error cases, the Service may assess and send a notice of assessment of additional tax without using deficiency procedures.

  4. IRC Section 6213(b)(2)(A) allows the taxpayer 60 days from the date of the math error notice (the 23C date) to request abatement of the additional tax specified in the notice. If the request is submitted via U.S. mail, use the postmark date to determine if the response was timely.

  5. If the taxpayer makes a timely request for an abatement, treat the response as a protest. See IRM 21.5.4.4.4., Math Error Substantiated Protest Processing, or See IRM 21.5.4.4.5., Math Error Unsubstantiated Protest Processing, as appropriate.

  6. Where the math error adjustment creates an outstanding liability subjecting that debt to a collection process, the taxpayer may contest that liability under the collection due process procedures.

  7. If, during a taxpayer contact it appears a hardship situation may exist, complete Form 911, Request for Taxpayer Advocate Service Assistance, and refer the taxpayer to the Taxpayer Advocate Service (TAS). See IRM 13.1.7.2, Taxpayer Advocate Case Criteria, or IRM 21.1.3.18, Taxpayer Advocate Service (TAS) Guidelines, for more information.

    Note:

    Prior to release of any tax information to a taxpayer or his/her representative, appropriate Disclosure authentication must be made. Please see IRM 21.1.3.2.3, Required Taxpayer Authentication, and IRM 11.3.2.6.1, Leaving Information on Answering Machines/Voice Mail.

21.5.4.2  (10-01-2007)
What Is a Math Error

  1. Mathematical or clerical errors involve the following:

    1. An addition, subtraction, multiplication, or division error shown on any return.

    2. An incorrect use or selection of information for a filed return from tax tables, schedules, etc., provided by the IRS, if such incorrect use is apparent from the existence of other information on the return.

      Example:

      A married taxpayer files a separate Form 1040 from his/her spouse under filing status married filing separately, however when figuring the amount of tax on taxable income enters the amount for taxpayers filing married filing jointly.

    3. An entry on a return inconsistent with an entry on a schedule, form, statement, or list filed with the return.

    4. An omission of information required on the return to substantiate an entry.

    5. An entry on a return of a deduction or credit in an amount which exceeds a statutory limit, if such a limit is a monetary figure, a percentage, a ratio, or a fraction, and if the items entered into the application of this limit appear on the return.

      Example:

      A taxpayer claims an IRA deduction even though her modified adjusted gross income exceeds the statutory limit allowable for claiming an IRA deduction.

    6. Missing or incorrect TINs for personal exemptions for the primary and secondary taxpayers, dependents, Child and Dependent Care Credit, EIC, Child Tax Credit, Lifetime Learning Credit, or HOPE Scholarship Credit.

      Note:

      Effective 1/1/05, and effective for all tax periods, the taxpayer will be considered to have used an incorrect TIN if information provided by the Social Security Administration (SSA) indicates the person to whom the TIN was issued was deceased prior to the beginning of the tax period for which it is being used to claim a Section 151 (personal exemption), Section 21 (Child Care Credit), Section 24 (Child Tax Credit), Section 25A (Education credit), or Section 32 (EIC) credit.

    7. A return claiming EIC, if EIC claimed in a previous year was disallowed through deficiency procedures and Form 8862, Earned Income Credit Eligibility, was not filed with the return.

      Exception:

      Form 8862 is not required if the EIC is claimed without a qualifying child, and the only reason the EIC was disallowed in the earlier year was that a child claimed as a qualifying child was determined not to be a taxpayer's qualifying child.

      Mathematical or clerical error procedures cannot be used where the disallowance of the EIC is due to either the 10-year ban for fraud under IRC Section 32(K)(1)(B)(i) or the 2-year ban for reckless disregard of the rules and regulations under IRC Section 32(K)(1)(B)(ii).

    8. An entry claiming EIC, based on self-employment income on which self-employment tax has not been paid. See IRM 21.6.3.4.2.7.7, EIC and SE Tax.

    9. A return claiming EIC and the primary and secondary taxpayers do not meet the age requirements when there is no qualifying child.

    10. The inclusion of a required TIN if it is of an individual whose age affects the credit amount and when a different age affects the computation of the credit.

      Example:

      A taxpayer claims the child tax credit for a dependent who was over age 16 at the end of the tax year.


      Note:

      With regard to EIC and the Child Tax Credit, taxpayer shall be treated as having omitted a TIN if information provided by taxpayer on the return reflects an individual's age different than the individual's age based on information provided by the TIN issuer (Social Security Administration or, in some cases, the IRS).

21.5.4.2.1  (12-01-2003)
What Is Not Considered A Math Error

  1. The following are not considered mathematical/clerical errors for purposes of the 60–day abatement request:

    1. A correction to withholding or estimated tax payments.

    2. Any tax decrease resulting in a larger refund than taxpayer expected.

    3. When the Health Coverage Tax Credit (HCTC) is denied as part of the claim for refund on the return.

21.5.4.3  (10-01-2002)
Math Error Procedures Research

  1. The following sections provide research and general procedures for math errors. For more specific processing procedures, See IRM 21.5.4.4., Math Error Procedures Processing.

21.5.4.3.1  (10-01-2007)
Math Error Response Review

  1. When a taxpayer requests an abatement with or without substantiation within 60 days, the Service must abate the assessment. Treat the response as a protest and refer the case to Examination. Examination will make a determination, and if the taxpayer disagrees, the taxpayer will have the opportunity to appeal the determination prior to the notice of deficiency. If a notice of deficiency is issued, the taxpayer will have the opportunity to file a petition with the United State Tax Court.

  2. Do not recompute Estimated Payment (ES) penalties since the ES penalty computation is based on the original tax shown on the present or preceding year tax return.

  3. Taxpayers may file amended returns and not address the math error issue:

    If Then
    Taxpayer files amended return and does not specifically address the math error issues Consider the amended return an agreement.
    It appears taxpayer did not receive the math error notice

    1. Do not consider the amended return a reply to the math error case.

    2. Keep the math error condition in effect for the full time period so taxpayer can exercise abatement rights.

    Example:

    The amended return would not be considered a reply to a math error notice, if the date of the notice is later than the date the taxpayer signed the amended return.

  4. Determine whether the original return is required. When requesting the original return in response to a math error protest, note on the charge-out "Request for Math Error Protest Case."

  5. Whenever a math error is identified and there are 120 or less days left to the Assessment Statute Expiration Date (ASED), contact the Statute function.

21.5.4.3.2  (10-01-2002)
Math Error Response Categories

  1. If taxpayer disagrees with the math error notice, determine under which category to process the protest under. The two types of math error categories are:

    • Substantiated Protest

    • Unsubstantiated Protest

  2. Substantiated Protest occurs when a taxpayer provides supporting documentation either orally or in writing, which proves the math error incorrect. See IRM 21.5.4.4.4., Math Error Substantiated Protest Processing.

  3. Unsubstantiated Protest occurs when a taxpayer fails to provide supporting documentation either orally or in writing to prove the math error is incorrect. See IRM 21.5.4.4.5., Math Error Unsubstantiated Protest Processing.

21.5.4.4  (10-01-2002)
Math Error Procedures Processing

  1. The following sections provide specific processing procedures for Math Error. See IRM 21.5.4.3., Math Error Procedures Research, for more general research procedures.

21.5.4.4.1  (10-01-2007)
Setting the Initial Math Error Action

  1. If while processing an amended return, a math error is detected, follow the procedures below to set the initial math error on the module:

    1. Recompute the tax and/or credits on the amended return.

    2. Adjust the tax and/or credits to the corrected amounts on the amended return.

    3. Input the adjustment using Blocking Series (BS) 77/78.

      Note:

      If the original return was filed electronically, use Blocking Series 77 with a TRPRT or IMFOLR print attached. Do not use Blocking Series 78.

    4. Use Source Code (SC) 6 and the appropriate Reason Code(s) (RC).

    5. Give taxpayer a detailed explanation of the math error. When an explanation is too lengthy or complicated to explain, include an exhibit illustrating taxpayer's error.

      Example:

      A copy of the return showing taxpayer's figures and corrected figures, worksheets, schedules, tax tables, etc.

    6. Identify the math error on the return or attach a history sheet to the source document that explains the error.

      Note:

      BS 77/78 generates the "—G" freeze deferred action for 12 cycles on Master File (MF) and the appeal rights indicator.

21.5.4.4.2  (10-01-2002)
Service Identified Math Error with Examination Criteria

  1. When you identify a math error, and examination criteria are present:

    1. Input the adjustment transaction.

    2. Use BS 77/78 to set the math error condition.

      Note:

      Use Blocking Series 77 with the TRPRT or IMFOLR print attached if the original return was filed electronically. Do not use blocking series 78.

    3. Input a second Transaction Code (TC) 290 for zero amount.

    4. Use BS 74.


  2. When taxpayer agrees with the math error, research Integrated Data Retrieval System (IDRS) and the Audit Information Management System (AIMS) files and route the agreement to the Examination Function shown on the AIMS print, for association with the case.

21.5.4.4.3  (10-01-2006)
Processing Responses to Math Error Notices

  1. Correction of a math error on an original filed return is not an amended return or claim for which the amended claim date is required. Do not use an amended claims date when correcting a math error posted with the original return.

  2. If a taxpayer is responding to a math error and also claiming an additional change to the original return, two adjustments will be necessary if working the claim 45 days or less from the received date, one without the amended claims date (for the math error issue) and one with the amended claims date (for the non-math error issue). Use hold code 4 on the first adjustment and a posting delay of 1 on the second. See IRM 21.5.3.4, General Claims Procedures, for more information.

    Note:

    Ensure the taxpayer receives the necessary information to explain both adjustments since the first adjustment will not have a related notice.

  3. When a reply is received after 60 days ( See IRM 21.5.4.1., General Math Error Procedures Overview) from the notice date and there is no –G freeze on the module:

    Note:

    For an unsubstantiated response, if the reply is received timely but the –G freeze has fallen off due to a delay in processing the response, reset the math error and process the response ( See IRM 21.5.4.4.5., Math Error Unsubstantiated Processing) using posting delay codes appropriate to the adjustment.

    If Then
    Taxpayer provides substantiation Follow substantiation procedures ( See IRM 21.5.4.4.4., Math Error Substantiated Protest Processing). If the claim or request for abatement/refund is after the normal Refund Statute Expiration Date (RSED), refer to IRM 25.6.6.4.4, Reconsideration After the RSED Where Notice of Claim Disallowance Not Sent.
    Taxpayer does not provide substantiation Follow IRM 21.5.3.4, General Claims Procedures, to reject/disallow the claim.

  4. Resolve math error inquiries received within the 60 day period as follows:

    If Then
    Taxpayer questions the reason for the math error Research Command Code (CC) RTVUE or BRTVU to answer taxpayer's questions.
    Research does not provide sufficient information

    1. Control the case.

    2. Request the return.
    If taxpayer does not understand the math error or requests further information

    1. Do not treat as an Unsubstantiated Protest.

    2. Provide an explanation to the taxpayer.
    Taxpayer disagrees with the assessment Treat the response as a protest. See IRM 21.5.4.4.4., Math Error Substantiated Protest Processing or See IRM 21.5.4.4.5., Math Error Unsubstantiated Math Error Processing, as appropriate.

  5. Take the following actions when the taxpayer agrees with the math error:

    If And Then
    Agreement is not on an amended return There is an zero or credit balance Follow classified waste procedures in IRM 21.5.1.4, General Adjustments Procedures.
    Agreement is not on an amended return There is a debit balance Input TC 290 for .00 with PC 6 to release the "–G" Freeze, if present.
    Agreement is on an amended return There is no debit balance. Input TC 290 for .00 to release the "A" freeze.
    Agreement is on an amended return There is a debit balance

    1. Input TC 290 for .00 with Source Document and Priority Code 6 to release the "–G" freeze.

    2. Input TC 290 for .00, NSD with a posting delay of one cycle to release the "A" freeze if no other issue involved.

21.5.4.4.4  (10-01-2007)
Math Error Substantiated Protest Processing

  1. A Substantiated Protest occurs when taxpayer provides supporting information to indicate the math error condition is not correct. For a Substantiated Protest:

    1. Oral statement adjustments are limited to the amount shown on the original return.

    2. Do not ask taxpayer to provide written documentation (except for age verification for Child Tax Credit and EIC or responses to a denial due to the date of death for exemption, dependent care benefits, Child Tax Credit, EIC and Education Credits) unless tax forms or schedules are missing.

    3. Validate the substantiation.

    4. Review any qualifications needed to allow adjustment..

    5. Check RTVUE/IMFOLI or BRTVU/BMFOL for further verification.

    6. Input the abatement transaction using CRN 764 when an EIC adjustment is required and process as a normal adjustment case. See IRM 2.4.16, Command Codes REQ54 and ADJ54, for Command Code ADJ54 instructions.

    7. See IRM 21.6.3.4.2.7, Earned Income Tax Credit (EIC), for specific EIC math error information.

    8. See Exhibit 21.5.4-1., Actions On Math Error Cases, for general procedures on math error cases

    9. Determine whether Examination criteria exists.

    10. Do not reduce tax below the amount reported on the original return or allow credit in excess of the amount claimed on the original return without a written statement from the taxpayer.

      EXCEPTION:

      If Then

      1. There is no change to the income reported on the original return, and

      2. You are adjusting the taxpayer's return due to a TIN related math error, and

      3. Other math errors were issued that affected the amount of total tax, and the correction results in a reduction of total tax originally reported.

      1. Make appropriate adjustment to tax to agree with other corrections requested by the taxpayer.

      2. Advise taxpayer of adjustment.

      1. There is no change to the income reported on the original return, and

      2. The taxpayer indicates that an incorrect amount of tax from the tax tables was claimed on their return, and

      3. The error is confirmed.

      1. Make appropriate adjustment to tax to agree with other corrections requested by the taxpayer.

      2. Advise taxpayer of adjustment.

    11. When adjusting an account changes, adds or deletes an Social Security Number (SSN), see IRM 21.6.1.6, Command Code DUPED and DDBCK, for instructions.

    12. Refer to IRM 3.13.5.29, Inputting Entity Changes via CC ENMOD/ENREQ, for correction of entity issues involving invalid TINs.

    13. Refer to IRM 3.21.263.7.1.6 , Math Errors, for procedures on math errors involving ITINs.

    Note:

    The receipt of Form 8862, Information to Claim Earned Income Credit After Disallowance, does not provide substantiation that the math error condition is not correct (See IRM 21.6.3.4.2.7.15, EIC Recertification, for more information).

  2. If an open TC 420 (and no TC 576 or TC 570) is present on the module, regardless of the AIMS Status, and taxpayer submits a substantiated protest:

    If Then
    The correct abatement can be determined

    1. Input TC 29X, for appropriate amounts.

    2. Input any appropriate CRN's.

    3. Use BS 00 or 18.

    4. PC 1.
    The correct abatement cannot be determined from the information the taxpayer filed

    1. Contact the taxpayer for copy of original return.

    2. Suspense case for 40 days.

    3. If taxpayer responds follow procedures above.

  3. When an open TC 576 or TC 570 is present and taxpayer files a substantiated protest:

    1. Input TC 470 cc 94.

    2. Input TC 29X.

    3. Use CRN 764 when appropriate.

    4. Use PC 7.

    5. Use BS 70.

    6. Input a Posting Delay Code of one cycle.

    7. Send taxpayer a letter of explanation and, if there is a credit balance, explain why refund is being held.

    Note:

    Adjust penalties and interest if needed. Route the cases in (2) and (3) above to the Examination function shown on the AIMS print. Notate on the routing slip "Substantiated Protest Allowed."

21.5.4.4.5  (10-01-2006)
Math Error Unsubstantiated Protest Processing

  1. An Unsubstantiated Protest occurs when taxpayer does not provide supporting documentation to prove the math error is incorrect. If, after explanation, taxpayer does not agree with assessment, explain taxpayer's abatement rights, and the consequences of abatement (the case may be referred to Examination and the refund may be held). Ask whether taxpayer wishes to request abatement. An abatement request may be written or oral. Taxpayer is entitled to abatement even if he/she does not substantiate. After abatement, any assessment must be made pursuant to deficiency procedures.

  2. If the amount claimed ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ ≡ , (See IRM 21.5.1.4.12, Tolerances) do not follow the procedures shown below. Adjust the account.

  3. If taxpayer requests abatement, the following action is required:

    1. Input TC 470 cc 94.

    2. Input the abatement with TC 29X and any appropriate Reference Numbers.

    3. Input a Posting Delay Code of one cycle on CC ADJ54.

    4. Use BS 74.

    5. Use the correct Source Code.

    6. Use the appropriate Reason Code.

    7. Use Hold Code 3.

    8. Use Priority Code 7.

    9. Adjust penalties and interest as appropriate.

    10. Issue a letter and, if there is a credit balance, explain why refund is being held.

    Caution:

    Failure to input a TC 29X after a TC 470 cc 94 generates an AM24 transcript to adjustments.

    Note:

    An adjustment to an account with a previously posted TC 160 requires a secondary TC 16X to prevent an Unpostable 334 RC 6 situation. When using BS 74 with PC 7, and the TC 160 does not need to be adjusted, a TC 160 for $.01 can be used.

  4. When the protest is unsubstantiated and the module is open on AIMS, process as follows:

    1. Input TC 470 cc 94.

    2. Input TC 29X and TC764, where appropriate.

    3. Input a Posting Delay Code of one cycle.

    4. Use BS 74.

    5. Use HC 3.

    6. Use PC 7.

    Note:

    Route these cases to the Examination function shown on the AIMS print. Notate on the routing slip "Unsubstantiated Protest Allowed."

  5. If the abatement is on an Exempt Organization (EO) return, contact the EO Examination Classification Site. See IRM 21.7.7.4.15.3,  Routing Procedures for EO CATA Cases, for the address and phone number. Inform them that a math error abatement requiring reassessment has been made. Give them the taxpayer's Name, Form Number, Master File Tax (MFT), Tax Period, Name Control, Employer Identification Number (EIN), and the amount. Classifications sites will input TC 424 to secure these returns.

21.5.4.4.6  (10-01-2002)
Multiple Math Error Responses

  1. Multiple Math Error Responses could include agreements and protests.

    If And Then
    Response falls into one category   Process the case according to the specific category procedures.
    Response falls into more than one category   Calculate tax relevant to each math error.
    Response is disagreed All substantiated

    1. Input TC 291 for the substantiated amount in the proper BS.

    2. Use appropriate Reason and Source Codes.
    Response is disagreed All unsubstantiated

    1. Input TC 470 cc 94.

    2. Use TC ADJ54.

    3. Use Posting Delay Code.

    4. Input TC 291 or TC 29X with any CRNs that apply, for the unsubstantiated amount to post one cycle later.

    5. Use PC 7.

    6. Use BS 74.

    7. Use HC 3.

    8. Use appropriate Reason and Source Codes.
    The response is partially substantiated, and partially unsubstantiated, or partially agreed, substantiated and partially unsubstantiated.   For the substantiated amount:

    1. Input TC 291 or TC 29X with any CRNs that apply.

    2. Use BS 05.

    3. Input TC 470 cc 94.

    4. Suspend case until adjustment posts.


    For the unsubstantiated amount:

    1. Input TC 291 or 29X with any CRNs that apply.

    2. Use BS 74, HC 3, PC 7, appropriate Reason and Source Codes.

  2. Take any necessary follow-up action on Individual Retirement Account File (IRAF).

21.5.4.4.7  (10-01-2006)
Math Error with Injured Spouse

  1. Refer math error inquiries where the taxpayer filed an original return with Form 8379, Injured Spouse Claim and Allocation (TC 150, Blocking Series 92), as follows:

    If Then
    The math error is substantiated and the injured spouse claim is open.

    1. Adjust the account ( See IRM 21.5.4.4.4., Math Error Substantiated Protest Processing).

    2. Use Hold Code 1 on the adjustment to prevent release of the overpayment.

    3. Input taxpayer's daytime telephone number using TELEA .
    The math error is substantiated and the injured spouse claim is closed. The response is worked in Accounts Management at the campus where the injured spouse claim was processed. Prepare Form 4442/e-4442, Inquiry Referral and:

    1. Note the issue involves both a math error and an injured spouse claim.

    2. Provide the validated information necessary for the AM caseworker to be `able to adjust.

    3. Input a history item or close your control base: 4442TOXX (XX=location where original return was filed - e.g. Andover = 08), SUBMATHERR, INJSPCLAIM.

      Note:

      E-4442 will automatically create control input.


    To resolve the Form 4442:

    1. Request the original from files and if unable to secure, request taxpayer to fax a copy of the injured spouse claim.

    2. Open a control base to rework the injured spouse claim per IRM 21.4.6, Refund Offset.
    ````The math error is agreed and the injured spouse claim is open.

    1. Input a History Item, MEAGRDMMDD (MMDD = month/day).

    2. Input taxpayer's daytime telephone number using CC TELEA.
    The math error is agreed and the injured spouse claim is closed. Input TC 290 for .00 with Priority Code 6 (to release the –G freeze) if the account is in debit status.
    The math error is unsubstantiated and the injured spouse claim is open. Contact the employee with the open control before taking any action. Input history items and close your control base as needed.
    The math error is unsubstantiated and the injured spouse claim is closed. Follow normal unsubstantiated math error procedures. Prepare Form 4442, Inquiry Referral, to Examination to alert them to an Injured Spouse and Unsubstantiated Protest.

    Note:

    If an open control is present, coordinate any action with the employee having the open control per IRM 21.5.2.3, Adjustment Guidelines - Research.

Exhibit 21.5.4-1  (10-01-2002)
ACTIONS ON MATH ERROR CASES

Issue TC SC PC Closing Code Blocking Series Hold Code Freeze Code Set Freeze Code Remove
Agreed (debit balance) TC 290 2 PC 6   BL05     –G
Agreed (amended return, no debit balance) TC 290 2     BL05     –G
Disagreed - substantiated TC 29X 2     BL00/05     –G
Disagreed - substantiated - TC 420 on module TC 29X 2 PC 1   BL 00/18      
Disagreed - substantiated - TC 576/570 TC 470 TC 29X (1 cycle posting delay) 2 PC7 cc 94 BL 70      
Disagreed - unsubstantiated TC 470 TC 29X (1 cycle posting delay) 2 PC 7 cc 94 BL 74 3 J
R 		–G
J
Math error found during adjustment processing TC 29X 6     BL 77/78   –G  
G freeze set erroneously TC 470 TC 474 TC 29X 2   cc 94
cc 94 		    J –G
J
TC 472 cc 94               J

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