Alpha Codes are the 4-letter character codes used to identify a specific unit or office within NPS. For the various parks, the code is typically the first 4 letters of a unit with a single word name (e.g., YELL for Yellowstone National Park), or the first two letters of the first word followed by the first two letters of the second word for units with two or more word names (e.g., GRTE for Grand Teton National Park). There are some exceptions. For example, Carlsbad Caverns is CAVE, as opposed to CACA, and Lake Mead is LAKE as opposed to LAME. These codes were changed to prevent the parks from having codes that created names inconsistent with the nature of the parks themselves.

Some organizations and offices within NPS have 3-letter codes or have some combination of characters that differ from the norm. This list provided below has all of the current codes along with several hundred codes that are obsolete and/or are no longer used, mostly from units that no longer exist or that have been renamed or redesignated.

SOURCES: NPS, National Archives

CURRENT VERSION: 3.07 [PDF]

Changes from last version: Added 50+ codes, corrected a couple of spelling errors.

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ARCHIVED VERSIONS

3.06 [PDF]

3.05 [PDF]

3.04 [PDF]

3.03 [PDF]

3.02 [PDF]

3.01 [PDF]

3.00 [PDF]

Changes from last version: New production format; handful of new codes

2.00 [PDF]

Changes from last version: Added 200 codes, including obsolete codes; new format, new version numbering for consistency

2200-001-00A [PDF]

Changes from last version:  Added Blackwell School NHS

2200-001-000 [PDF]