---
title: "Adverse action notice"
description: "The notice a US creditor must give when it denies or worsens credit, stating the specific principal reasons."
canonical: https://aigovernanceengineer.com/glossary/adverse-action-notice
author: "Jorge García Aibar"
license: "CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)"
doi: https://doi.org/10.5281/zenodo.22956197
version: "0.5.0"
updated: 2026-09-25
---

# Adverse action notice

The notice a US creditor must give when it denies or worsens credit, stating the specific principal reasons [1]. The reasons must be accurate even when the decision comes from a complex model, so reason codes need a fidelity test.

- Developed in: [ch. 20, Credit and lending](https://aigovernanceengineer.com/bok/existing-law#credit-and-lending)
- Chapters: [ch. 16, Fairness & XAI](https://aigovernanceengineer.com/bok/fairness-and-explainability) · [ch. 20, Existing Law](https://aigovernanceengineer.com/bok/existing-law)
- Contrast with: [Decision notice](https://aigovernanceengineer.com/glossary/decision-notice)
- In the glossary chapter: https://aigovernanceengineer.com/bok/glossary#t-adverse-action-notice

## Sources

[1] 12 CFR 1002.9 (Regulation B, notifications) (1002.9(b)(2) statement of specific principal reasons for adverse action; Supplement I commentary; text as of 2026-09-01). eCFR. 2026-09-01. https://www.ecfr.gov/current/title-12/chapter-X/part-1002/section-1002.9 (verified: primary)