Use Form SS-4 to apply for an employer identification number (EIN). An EIN is a 9-digit number (for example, 12-3456789) assigned to employers, sole proprietors, corporations, partnerships, estates, trusts, certain individuals, and other entities for tax filing and reporting purposes.
Note: Keep the Form SS-4 information current. Use Form 8822-B to report changes to your responsible party, address or location. Changes in responsible parties must be reported to the IRS within 60 days.