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637 Registration Program

Under the Code and regulations, each person who engages in certain specified activities relating to excise tax must be registered by the IRS before engaging in that activity. In other cases, a person is required to be registered by the IRS in order to receive an excise tax benefit, such as, the right to sell or buy an article tax free or to file a claim. Taxpayers may use Form 637, Application for Registration (For Certain Excise Tax Activities), to apply for registration for activities under sections 4101, 4222 and 4682 of the Internal Revenue Code. Depending on the activity applied for, the person must meet certain registration tests in order to receive an approved registration number. The registration tests vary according to the activity; it may include an inspection of the person’s business premises. Each business unit that has, or is required to have; a separate employer identification number is treated as a separate person, and must submit their own Form 637 application.

The address to mail your Form 637 is:

Department of the Treasury
Internal Revenue Service Center
Excise Operations Unit - Form 637 Application
Cincinnati, OH 45999

Online Form 637 Registration Status Check

This Web application provides the ability for businesses to confirm whether individuals/companies have a valid IRS registration.

Form 637 Revised What’s New

The IRS revised Form 637, Application for Registration (For Certain Excise Tax Activities), to enable taxpayers to apply for registration with the IRS as a producer of second generation biofuel, and a qualified retailer.

New activity letter SB was added for producers of second generation biofuel. Current CB registrants will not need to reapply for the new SB registration.  Activity letter CB is removed because it is no longer applicable. The second generation biofuel credit is claimed on the producer’s income tax return.

Activity letter QR is added for qualified retailers of diesel fuel or kerosene sold in Alaska for nontaxable uses.  Taxpayers that have already been issued a correspondence letter of registration as a qualified retailer do not need to reapply.

Activity letter W, operator (other than state or local government) of a diesel-powered train, is removed because it is no longer applicable. Consequently, effective January1, 2007, train operators are no longer subject to liability under IRC section 4041 and are therefore no longer required to register under IRC section 4101.

The IRS will register a taxpayer only if the IRS determines that the taxpayer meets the applicable registration requirements.  A taxpayer is not registered until the IRS issues a letter of registration, which includes a registration number, to the taxpayer.


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Page Last Reviewed or Updated: 19-Sep-2014