The hours of operation are 7 a.m. However, you will need Adobe Reader installed if you would like to receive a confirmation letter online.This confirmation letter is known as Form CP 575 and is mailed to the address mentioned in your Form SS-4 application. What you need before you start your registration. Federal Employer Identification number (FEIN). 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. New businesses must file a business license application within 75 days of the date business began. 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. Employee Name: Employee ID: Employee Contact. First, you will need to contact the Zoning Department and fill out a Use Permit Application.