National Taxonomy of Exempt Entities

The National Taxonomy of Exempt Entities (NTEE) is a used by the Internal Revenue Service (IRS) and NCCS to classify U.S. tax-exempt organizations. A specialist from the IRS assigns an NTEE code to each organization exempt under I.R.C. § 501(a) as part of the process of closing a case when the organization is recognized as tax-exempt.

Source: Wikipedia — National Taxonomy of Exempt Entities (CC BY-SA 4.0)