Question Does a small company that operates as a sole proprietorship need an employer identification number (EIN)? Answer A sole proprietor without employees who isn’t required to file any excise tax return and hasn’t established a pension, profit-sharing, or retirement plan doesn't need an EIN (but can get one). In this instance, the sole proprietor uses his or her Social Security number (instead of an EIN) as the taxpayer identification number. However, if at any time the sole proprietor hires an employee, needs to file an employment or excise tax return, or is establishing a pension, profit-sharing, or retirement plan, then the sole proprietor will need an EIN for the business and can't use his or her social security number. If you have an existing EIN as a sole proprietor and become a sole owner of a Limited Liability Company (LLC) that has employees, needs to file an employment or excise tax return, or is establishing a pension, profit sharing, or retirement plan, you need to get a separate EIN for the LLC. Additional Information Publication 1635, Employer Identification Number - Understanding Your EIN Publication 334, Tax Guide for Small Business (For Individuals Who Use Schedule C) Form SS-4, Application for Employer Identification Number (PDF) Small business and self-employed tax center Category Small business, self-employed, other business Sub-Category Form SS-4 & employer identification number (EIN)
