Service number (United States Coast Guard)

United States Coast Guard service numbers were first created in the later half of 1921. In 2004 the Coast Guard began using Employee Identification Numbers, or EMPLIDs, to replace the Social Security Number on official forms.

Coast Guard officer service numbers were unique amongst the military branches in that the entire range of officer numbers was declared upon the initial creation of the service numbers. The officer range extended from #1 to 100,000 and these numbers had yet to be exhausted by the discontinuation of Coast Guard service numbers in 1974.

Like the Navy and Marine Corps, the Coast Guard set aside the early service numbers for retroactive presentations; however, for various reasons, the Coast Guard never enacted this project and never issued retroactive officer service numbers. Thus, officer numbers 1 through 999 remained un-issued with the first Coast Guard officer service number being #1000 which was issued to Joseph F. Farley. The next range of Coast Guard officer numbers, 1001 through 20,000 were reserved for issuance to officers of the Regular Coast Guard. These numbers were typically issued to graduates of the United States Coast Guard Academy and other Regular Guard appointees. The Regular Coast Guard officer service number range had yet to be reached in 1974 when service numbers were discontinued.

Coast Guard officer numbers above 20,001 were reserved for members of the United States Coast Guard Reserve as well as Coast Guard warrant officers and other "non-regular" Coast Guardsmen. Officer numbers from 20,001 to 60,000 were used into the 1950s and, by February 1957, non-regular officer service numbers had reached #60,393. The 1960s and early 1970s saw the issuance of service numbers into the 70,000 and 80,000 range while 80 and 90 thousand service numbers had been used since 1948 for special uses such as cadets at the Coast Guard Academy.

The first Coast Guard enlisted service numbers began at #100,000 with a range to 200,000. The purpose of beginning Coast Guard enlisted numbers in this range was to ensure that no enlisted Coast Guardsman would have a number previously assigned to an officer.

The first enlisted service number was assigned to Mason B. Herring. Service numbers were issued to enlisted personnel, based on date of entry, through the 1920s and early 1930s. In the mid 30's, the Coast Guard also began a project to retroactively assign service numbers to former members of the Revenue Cutter Service and Lifesaving Service. These numbers would eventually range from 149,237 through 200,000. It was also at this point that the Coast Guard began to write enlisted service numbers using the format "123-456" with an alternate method of replacing the dash with a significant space.

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