Print your EIN confirmation letter for your records. Who can use this tool.The only two ways to get an EIN Verification Letter (147C) is to call the IRS at 1-800-829-4933, or to mail the IRS a written request. If you apply online, you can download the EIN Confirmation Letter at the end. This confirmation letter is known as Form CP 575 and is mailed to the address mentioned in your Form SS-4 application. The Business License Application (BLA) is a simplified application used to apply for many state and city endorsements, registrations, and permits. The simplest way to get a copy of an EIN verification letter is to call the IRS. Follow the below process to obtain a tax ID verification letter. How to Contact the IRS for EIN Verification Letter? The simplest way to get a copy of an EIN verification letter is to call the IRS.