---
title: CP503 Notice Explained: What to Do Next | TaxTruce
url: https://taxtruce.com/notices/cp503
updated: 2026-10-29
---

# CP503, explained

Second reminder you still owe.

Updated October 8, 2026[Fact checked](/editorial-standards)

How urgent**High**

Second reminder you still owe.

The short answer

A CP503 is the second reminder that you owe. The IRS has not seen a payment or reply to its earlier notices. Pay by the date on the notice to stop more penalties and interest, or set up a plan. A lien may come next.

## Key facts

* It is the second reminder for the same balance.
* The IRS says it may file a Notice of Federal Tax Lien if it has not already.
* A lien can make it harder to get credit.

## Where it falls

1. [**1. CP14**First bill for unpaid tax](/notices/cp14)
2. [**2. CP501**First reminder you still owe](/notices/cp501)
3. [**3. CP503**Second reminder you still owe](/notices/cp503)
4. [**4. CP504**Notice of intent to levy](/notices/cp504)
5. [**5. LT11 or Letter 1058**Final notice of intent to levy and your right to a hearing](/notices/lt11)

## What to do next

* Pay the full balance by the due date, or apply for a plan.
* Already paid or fixed it? Call anyway so your account shows it.
* You can ask for a Collection Appeals Program appeal before collection starts.

Check your balance in your own [IRS online account](https://www.irs.gov/payments/your-online-account), and use the phone number on the notice or on irs.gov.

Results depend on your situation. Not every case qualifies.

## Common questions

What is a CP503 notice?

A CP503 is the second reminder that you owe. The IRS has not seen a payment or reply to its earlier notices. Pay by the date on the notice to stop more penalties and interest, or set up a plan. A lien may come next.

How urgent is a CP503?

High. Act by the date on the notice so it does not move up the ladder. The date on your notice is the one that counts.

## Sources

1. [IRS: Understanding your CP503 notice](https://www.irs.gov/individuals/understanding-your-cp503-notice)

Run the numbers with our [free tax tools](/tools), like the penalty and payment plan math.