Credit Reference (CRN) and Item Reference Numbers (IRN)

CRN and IRN are sometimes used interchangeably, when discussing adjustments. IRNs (also known as Item Adjustment Codes) are used to adjust tax, wages and general ledger information recorded in IDRS. CRNs are used to adjust applicable credits.

CRNs and IRNs are input in IDRS in the CD field of CC ADJ54 the response screen from the input of CC REQ54.

A maximum of four credit reference numbers can be input at one time on MFTs 02, 05, 33, 34 and 61. All other MFT’s accept a maximum of eight credit reference numbers.

Review IRNs and CRNs carefully before transmitting REQ54 adjustments. Forgetting a trailing minus or an incorrect input of cents (as applicable) can cause adjustments to unpost.

If you have further questions on credit and item reference numbers for adjustments, see the following subsections for specific CRN and IRN numbers by Form and MFT. In addition, for more information see IRM 21.7, Business Tax Returns and Non-Master File Accounts and Section 8C of the Doc 6209.