The provider’s social security number is needed for tax reporting purposes. Note that in the Insurance Catalog, the option should be selected to use the Federal employer tax identification number. Unless required by law or special contract, it is advisable to NOT use your social security number on any document from which it could be stolen and used for identity theft. The option of printing either the SSN or the EIN in box 25 of the CMS-1500 is selected in the Insurance catalog.