When doing a IRA to IRA rollover how do you determine 60 days from receipt? How does the IRS know the date you received the IRA?

from the date it arrives in the mail since the funds cannot be rolled over until the employee has possession of the check. The IRS doesnt know when the 60 days begins or ends because nothing is reported by the payor to the IRS as to the date the payment is mailed. Yes its an honor system (just like reporting the date/price a security was purchased for cap gains), basis in the home, etc)

Thank you for your help on this

Needless to say, it isn't very difficult for the IRS to approximate when you received the rollover. All they have to do is look at the date the funds were distributed. And that date WILL appear on your final brokerage statement.