How are employer identification numbers (Form SS-4) obtained?

You must have an employer identification number (EIN), which can be obtained by filing Form SS-4, Application for Employer Identification Number, or by applying online. This nine-digit number, which takes the form 00-0000000, is used to identify corporations, partnerships, nonprofit associations, trusts, and similar non-individual entities. For a sample Form SS-4, see ¶36,605 .

Do not confuse your EIN with your social security number, which takes the form 000-00-0000. Social security numbers are used to identify individuals, employees, and estates of decedents.

The EIN must be used on all correspondence, documents, returns, statements, and deposit forms. You should only have one EIN. If you have more than one and have not been advised which to use, contact the IRS office where your returns (Form 941) are filed.

When should you apply for an EIN? You must apply far enough in advance of the first required use of such number to permit issuance of the number in time for compliance with the requirement. The Form SS-4 instructions state that you should expect it to take four to five weeks when applying by mail.

Only one application is required and only one EIN will be issued regardless of how many establishments a particular employer may have. This is true even though business may be conducted under more than one business or trade name. But be careful; each corporation of an affiliated group must be treated separately and each, therefore, must have its own EIN.

Tele-TIN. The IRS will assign an EIN over the telephone. To receive a number over the telephone, complete the SS-4 and then call the applicable number listed in the Form SS-4 instructions. The person making the call must be authorized to sign the form. Once the number is received, write the number in the upper right hand corner of the SS-4 and mail or FAX it immediately.

Requesting an EIN online. You can also request an EIN through a Web-based system that instantly processes requests and generates identification numbers.

A taxpayer accesses the Internet EIN system through IRS.gov and enters the required information. If the information passes the automatic validity checks, the IRS issues a permanent EIN to the taxpayer. If the information does not pass the validity checks, it is rejected. The taxpayer then has an opportunity to correct the information and resubmit the application. The Internet EIN application is interactive and asks questions tailored to the type of entity the taxpayer is establishing.

When the EIN application process is complete, the applicant has the option to view, print and save his or her confirmation notice, as opposed to waiting for the IRS to mail it. An EIN assigned through Internet submission is instantly recognized by IRS systems and can be used immediately for most business purposes.

New business. If you became the new owner of an existing business, do not use the EIN of the former owner. If you already have an EIN, use that number. If you become the owner of a corporation by acquiring its stock, use the corporation's EIN.

Changes in organization or ownership. If you already have an EIN, you may need to get a new one if either the organization or ownership of your business changes. If you incorporate a sole proprietorship or form a partnership, you must get a new EIN. Do not apply for a new EIN if you change only the name of the business.