Use this tool to get an EIN directly from the IRS in minutes for free. Once the IRS issues an EIN for your Arizona LLC, you will receive your official approval, known as an EIN Confirmation Letter (CP 575).To apply for an employer identification number, you should obtain Form SS-4 PDF and its instructions PDF. This step-by-step guide will walk you through completing your transaction privilege tax return online at AZTaxes.gov. Mail: Responsible parties can mail their completed Form SS-4 to the address listed on the form, and an EIN will be mailed back within 4-5 weeks. 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. 1. How and where do I submit documents for filing? It is highly recommended that you submit your filings on the A.C.C.'s website, eCorp. This confirmation letter is known as Form CP 575 and is mailed to the address mentioned in your Form SS-4 application. EIN Confirmation letter from IRS called CP 575, is issued to grant Federal Tax Id number known as Employer Identification Number (EIN).