IRS NOTICE REFERENCE
Understanding Your CP128 Notice
You have a remaining balance due on a tax period after an overpayment (offset-in) was applied to your account.
General information only. Not legal or tax advice.
Notice details
- Notice code
- CP128
- Category
- Balance due and collection
- Severity tier
- Tier 2 — Action or response expected. The IRS has taken or proposed an action and expects a response or payment.
- Governing law
- §6303; §6321 (Internal Revenue Code sections)
- Source
- IRS.gov — Understanding Your IRS Notice
What this notice is
You have a remaining balance due on a tax period after an overpayment (offset-in) was applied to your account.
Source: IRS.gov. Reproduced for reference. General information — not legal or tax advice.
What the IRS says to do
Read and review your notice carefully. It provides the date and amount of the payment(s) that we applied to your account. It may also suggest additional steps for you to take, depending on your situation. If you owe, pay the amount due now. If you're enrolled in the Electronic Federal Tax Payment System (EFTPS), you can use that method of payment instead of paying by check or money order. If you are not enrolled in EFTPS, make your check or money order payable to the United States Treasury. Write your employer identification number (EIN), tax form number, and tax period on your payment. Use the envelope enclosed with your notice.
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 5.19.1 — 5.19.1 Balance Due
- IRM 5.19.4 — 5.19.4 Enforcement Action
- IRM 5.1.1 — 5.1.1 Miscellaneous Collection Procedures
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-cp128-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.
Check this notice’s deadline (free tool)