One of the first things you do when starting a new business is obtain the proper business registration and tax-filing status. Most organizations must obtain an EIN or Employer Identification Number. The EIN, also known as a Taxpayer Identification Number (TIN) is a nine-digit number assigned to entities by the Internal Revenue Service. An EIN is used to identify a business. EINs are used by business entities such as sole proprietorships, corporations, partnerships, not-for-profit organizations, estates, government agencies and various other organizations. Generally, an EIN must be obtained for the business to file taxes.

Employer/Taxpayer Identification Number

An EIN becomes the permanent federal taxpayer identification number for that business once it is assigned. There is no cost to apply for an EIN. An EIN cannot be reused or reassigned to another organization. Even if it is never used to file federal tax returns or other government documents, the IRS cannot cancel an EIN.

Closing Your Account

If you determine you no longer need an EIN after you've received it, you can request that the IRS close your account. This may be necessary if the business was never in operation, for example. You can still use the EIN at a later date if necessary, as it will always belong to that business. The number simply becomes “inactive.” You can write to the IRS to close your account. You must indicate the reason you are closing the account and you’ll need to include a copy of the EIN Assignment Notice you received when your EIN was issued. You should also indicate the legal name of the business, the address and Employer Identification Number.

Tax-Exempt Organizations

The rules regarding EINs and tax-exempt organizations are much the same for closing the account of an EIN that was never used. You must send a letter requesting the closing for your account. In the letter you must state the reason you want to close the account. Include a copy of the EIN Assignment Notice or list the complete legal name of the organization, the EIN and the entity’s mailing address.

Other Business IDs

The IRS only issues EIN/TIN to certain individuals, businesses and tax-exempt organizations for federal taxes. You must check with your state employer identification number and the process for canceling or inactivating a state-issued EIN.