Transaction Codes (TCs) Overview

Transaction Codes (TCs) are 3-digit numeric codes that describe actions, assessments, payments, freezes, and updates applied to a tax module.

Do Not Memorize All 500+ Codes

For IMF customer support, you do not need to memorize every possible code in existence. Focus on the high-frequency TCs that tell the module's financial story.

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The Core 15 Codes to Master First

150, 290, 300, 301, 520, 521, 560, 570, 571, 806, 846, 971, 976, 977, 610

TC	General Meaning	Operational Impact / Why You Care
150	Original return posted	Establishes the original tax assessment and starts the module history.
290	Additional tax / adjustment	Used by IRS to assess additional tax or post a $0.00 system adjustment.
300	Examination deficiency assessment	Assesses additional tax resulting from an IRS audit/examination.
301	Abatement of TC 300	Reverses or lowers examination tax assessment.
520	Legal / court collection condition	Litigation, court action, or bankruptcy freeze placed.
521	Release of TC 520	Clears the legal/litigation condition.
530	Currently Not Collectible (CNC)	Suspends active collection due to hardship or unable-to-locate.
531	Release of TC 530	Closes CNC status; account returns to active inventory.
560	Statute-related transaction	Updates or maintains Master File ASED calculation.
570	Refund hold / Additional liability	Freezes refund issuance while condition is verified.
571	Release of TC 570	Clears the refund freeze; allows refund generation if no other holds.
610	Payment with return	Remittance submitted with original tax return.
806	Withholding credit	Posts Federal Income Tax Withheld (from Form W-2 / 1099).
846	Refund issued	Generates a check or direct deposit refund.
971	Action / Reference transaction	Descriptive action code indicator. Always check the Action Code (AC)!
976	Duplicate return indicator	Duplicate return received for the same tax period.
977	Amended return indicator	Form 1040-X / amended return posted to the module.

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Detailed Code Categories

Browse deeper documentation on specific code families:

• Assessment Codes (150, 290, 300, 301)
• Refund & Hold Codes (570, 571, 846, 806)
• Legal & Collection Codes (520, 530, 540, 550, 560)
• Payments & Remittances (610, 640, 650, 660, 670)
• TC 971 & Action Codes