If you have lost your EIN Verification Letter from the Department of Treasury, you can request a new one.
To do so, call the IRS Business & Specialty Tax Line toll free at 1-800-829-4933 between the hours of 7am and 7pm in your local time zone.
Request a 147c letter when you speak with an agent on the phone. Requesting a letter is free. They will either mail it to you or fax it to you.
You will be asked some security questions about your business to verify your identity. Potential questions include: your EIN number, the name and address of your business, the type of business income tax form you file and your name and position in the company.