A physical letter must be mailed indicating the ... Internal Revenue Service. "Do You Need an EIN?" Internal Revenue Service. "Form SS-4 Application for Employer Identification Number." ...

For instance, the 1040 form that most people use to file their ... incorporation and tax purposes or both, “In the EIN Letter that the IRS provides you, there will details about what tax filings ...

If you are not sure whether or not you should submit a form W-9, consult a tax professional. If you are a sole proprietor, you can enter either your SSN or EIN. If your business is a corporation ...