From
https://igotmyrefund.com/4464c-cp05-leaving-taxpayers-confused/
Why am I getting the 4464C letter from the IRS?
Simply put, your tax return is under review. This is not an audit notice. The review is part of a normal revenue protection program by the IRS. The IRS selects returns for review using various methods which include random sampling, computerized screening, and comparison of information received by the IRS such as Forms W-2 and 1099. The letter will indicate that they are reviewing your return for one or more of the following:
- Income you reported on your return
- Income tax withholding amounts
- Claims for tax credits
- Business Income
At the IRS, it is known as the Questionable Refund 3rd Party Notification Letter. It is sent from the Integrity & Verification Operations unit at the IRS. It signals to the taxpayer that the IRS may contact other parties such as your employer to verify information you reported on your return.
What should I do?
Nothing. It’s not time to call (unless you didn’t file a tax return.) If you receive a 4464C Letter from the IRS, you aren’t required to do anything. The letter indicates that if you haven’t received your refund or been contacted by the IRS in writing within 60 days from the date of the letter you can call for more information. The letter also tells you what to do if you received it and didn’t file a tax return.
