Understanding your CP531 notice

Notice details

Notice code

CP531

Category

Underreporter / income matching

Severity tier

Tier 2 — Action or response expected. The IRS has taken or proposed an action and expects a response or payment.

Governing law

§6201; §6212 (Internal Revenue Code sections)

Source

IRS.gov — Understanding Your IRS Notice

What this notice is

This first notice is sent to tell the taxpayer they may be subject to backup withholding for unreported or unpaid interest or dividend income.

Source: IRS.gov. Reproduced for reference. General information — not legal or tax advice.

What the IRS says to do

File Form 1040, U.S. Individual Income Tax Return PDF , if you haven’t already filed. Review your filed Form 1040 for underreported interest or dividend income. File an amended Form 1040 for any underreported interest or dividend income. Pay any taxes owed on Form 1040 with interest or dividend income.

This is the IRS’s own guidance reproduced from the IRS notice page. It describes the IRS’s process — it is not legal or tax advice from TaxRiskOS.

Governing IRS procedure (Internal Revenue Manual)

The IRS’s own internal procedures for handling this notice type are documented in the Internal Revenue Manual:

• IRM 4.19.3 — 4.19.3 IMF Automated Underreporter Program
• IRM 4.19.2 — 4.19.2 IMF Automated Underreporter (AUR) Control

Reference to published IRS procedure. General information — not legal or tax advice.

Official IRS reference

Read the official notice page on IRS.gov: https://www.irs.gov/individuals/understanding-your-cp531-notice

Related tools

TaxRiskOS is workflow software for practitioners — it captures the notice, computes the deadline, surfaces the escalation tier, and builds a document checklist. It documents process; it does not give advice or draft responses.

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