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CP503

Second Reminder Notice

Complete guide for tax professionals on responding to IRS CP503 notices, including deadlines, required documentation, and response strategies.

Response Deadline

10 days

IRS: 1-800-829-1040View on IRS.gov

What Triggers This IRS Notice

  • 1CP501 notice was not responded to
  • 2Balance remains unpaid
  • 3No payment arrangement has been made

What the IRS Is Claiming

  • The balance is still outstanding
  • This is the second reminder
  • Further collection action will occur without response

Key Deadlines and Response Timelines

This is an urgent reminder. The next notice (CP504) will be a final notice before levy action.

What Happens If You Do Not Respond

  • CP504 Intent to Levy notice will be sent next
  • Interest and penalties continue to accrue
  • Federal tax lien may be filed

Documentation Commonly Required

Copy of the CP503 notice
Financial documentation for payment plan
Records of any partial payments

When IRS Information Is Incorrect

  • 1
    Provide proof if balance was paid
  • 2
    Submit dispute documentation if applicable

How Tax Professionals Typically Respond

  1. 1

    Immediate payment or payment arrangement is crucial

  2. 2

    Apply for installment agreement before CP504 is issued

  3. 3

    Consider currently not collectible status if financially unable to pay

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Related Notices

CP2000

Income Discrepancy Notice

CP14

Balance Due Notice

CP501

Reminder Notice

CP504

Intent to Levy Notice

LT11

Final Notice of Intent to Levy