What is an IRS number or importer number?
The importer number (requested on Customs and Border Protection entry paperwork) is usually the IRS business tax number assigned to businesses. If you do not have an IRS business tax number, you may use your social security number in any paperwork requiring an importer number. If you do not have either an IRS business tax number or a social security number, you may request that an importer number be assigned for you by filling out a form 5106 and giving it to the CBP entry branch where you will be filing your customs entries. The regulations governing the issuance of an importer number are in 19 CFR 24.