A tax ID is not the same as a Social Security number, although there are some similarities in the way they are used. If you have both, make sure you use each appropriately to avoid committing a crime.
Social Security Number
A Social Security number, issued by the Social Security Administration, is a nine-digit series of numbers arranged in the following format: xxx-xx-xxxx. A Social Security number is necessary to get a job. It also serves as a form of identification and is often needed to open a bank account or get a loan. You can use your SSN to track your Social Security benefits and receive other government benefits. The SSA also provides numbers for non-citizens temporarily living in the United States.
A tax ID is also called an Employer Identification Number (EIN) or Federal Employer Identification Number. Like the SSN, it is a nine-digit series of numbers, but they appear in the following format: xx-xxxxxxx. The EIN is not issued by the SSA but by the Internal Revenue Service. It is for business entities for tax reporting purposes. Not every business must have one. However, you need one if you have employees; operate as a corporation or partnership; withhold taxes on income; have a Keogh plan; file tax returns on employment, excise, alcohol, tobacco or firearms; or are involved with organizations like trusts, estates, real estate mortgage investments, non-profits, farmers' cooperatives and plan administrators.
If you have an EIN, there are some situations in which you can use it instead of your SSN. For instance, if you are a sole proprietor opening a bank account for your business, you may use your EIN on your application. When a client asks for your taxpayer identification number on a W9, you may provide the EIN instead of your SSN. You can use the number for business-related situations but not for personal credit.
Penalties for Misusing an EIN
It is illegal to present your EIN as your Social Security number. For instance, some credit repair companies advise customers to apply for an EIN and use it in place of an SSN when applying for credit. This is a Federal crime and you could end up having to pay fines or serving jail time.