The hours of operation are 7 a.m. This EIN confirmation letter is called CP 575, and the IRS only mails the letter to the mailing address listed on line 4 of the SS-4 application.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. Apply for an FEIN online or contact the IRS at 1-800-829-1040. Related FAQs in Entity Registration. However, you will need Adobe Reader installed if you would like to receive a confirmation letter online. Read the instructions on this website. Enter the Letter ID from the top right corner of your letter. The License and Revenue Division assists businesses in the City of Montgomery when issuing and maintaining appropriate business licenses and sales tax numbers. This confirmation letter is known as Form CP 575 and is mailed to the address mentioned in your Form SS-4 application.