medium urgencytypical response window: 30 days
IRS Notice CP501: Reminder of Balance Due
What it means
Second notice for unpaid taxes — the collection process is underway.
What to do
Respond or pay; the next step is intent to levy.
Verify it's real. The IRS contacts you by mail first — never by phone, email, or text demanding payment. The notice includes a number in the top-right corner and instructions on irs.gov. When in doubt, log into your IRS online account rather than calling a number on the letter.
FAQ
What is IRS notice CP501?
Second notice for unpaid taxes — the collection process is underway.
How long do I have to respond to CP501?
You typically have 30 days from the notice date. The deadline is printed on the notice itself — use that, not this estimate.
Should I get professional help for CP501?
Yes — notices at this stage of the collection process are where an EA, CPA, or tax attorney can prevent enforcement and negotiate terms. Most offer a free consultation.