Army Serial Number Info
The following came from Army Regulation 615-30, dated 12 Feb 1942.
The system enabled one who knew the numbering system to tell from a serial number the component and corps area (later Service command and army area) from which a man had entered the Federal service, whether he had enlisted, or had been drafted through the Selective Service, and whether he had been a National Guardsman in his home state. Officer serial numbers always started with the letter O.
According to Army Regulation 615-30, dated 12 Feb 1942, Corps area commanders are charged with the assignment of Army serial numbers to all enlisted men within their respective areas, including exempted stations and commands, and oversea base commands.
For the Regular Army - Enlisted men to whom an Army serial number has never been assigned: Army serial numbers from the blocks shown below will be assigned to men enlisted in the Regular Army on or after July 1, 1940. The second digit indicates the corps area of enlistment.
1st Corps Area - 11,000,000 to 11,999,999
2nd Corps Area - 12,000,000 to 12,999,999
3rd Corps Area - 13,000,000 to 13,999,999
4th Corps Area - 14,000,000 to 14,999,999
5th Corps Area - 15,000,000 to 15,999,999
6th Corps Area - 16,000,000 to 16,999,999
7th Corps Area - 17,000,000 to 17,999,999
8th Corps Area - 18,000,000 to 18,999,999
9th Corps Area - 19,000,000 to 19,999,999
Hawaiian Department - 10,100,000 to 10,199,999
Panama Canal Department - 10,200,000 to 10,299,999
Philippine Department - 10,300,000 to 10,399,999
Puerto Rican Department - 10,400,000 to 10,499,999
For the National Guard - Army serial numbers from the following blocks will be assigned to members of National Guard units upon induction into Federal service, regardless of whether or not the man formerly had an Army, Navy, or other service number. The third digit indicates corps area of induction.
1st Corps Area - 20,100,000 to 20,199,999
2nd Corps Area - 20,200,000 to 20,299,999
3rd Corps Area - 20,300,000 to 20,399,999
4th Corps Area - 20,400,000 to 20,499,999
5th Corps Area - 20,500,000 to 20,599,999
6th Corps Area - 20,600,000 to 20,699,999
7th Corps Area - 20,700,000 to 20,799,999
8th Corps Area - 20,800,000 to 20,899,999
9th Corps Area - 20,900,000 to 20,999,999
Hawaiian Department - 20,010,000 to 20,019,999
Puerto Rican Department - 20,020,000 to 20,029,999
The serial number assigned at induction into Federal service will be retained thereafter upon enlistment or reenlistment for the Regular Army or Army of the United States.
For Men inducted into the Army - Army serial numbers from the following blocks will be used for trainees inducted under the Selective Training and Service Act of 1940, regardless of whether the man formerly had an Army, Navy, or Other service number, and will be retained thereafter upon enlistment or reenlistment for the Regular Army. The second digit indicates the corps area of induction.
1st Corps Area - 31,000,000 to 31,999,999
2nd Corps Area - 32,000,000 to 32,999,999
3rd Corps Area - 33,000,000 to 33,999,999
4th Corps Area - 34,000,000 to 34,999,999
5th Corps Area - 35,000,000 to 35,999,999
6th Corps Area - 36,000,000 to 36,999,999
7th Corps Area - 37,000,000 to 37,999,999
8th Corps Area - 38,000,000 to 38,999,999
9th Corps Area - 39,000,000 to 39,999,999
Hawaiian Department - 30,100,000 to 30,199,999
Panama Canal Department - 30,200,000 to 30,299,999
Philippine Department - 30,300,000 to 30,399,999
Puerto Rican Department - 30,400,000 to 30,499,999
Consecutive numbers - Consecutive numbers will not be assigned to men of the same surname. Canceled numbers will not be held available for reassignment.
The Army serial number assigned to an enlisted man is part of his official designation and, except as indicated will ordinarily appear in every military record in which his name appears, including every letter, telegram, order, report, pay roll, etc., at least once, preferably where the name first occurs.
Special care must be taken that the correct Army serial number is used for the reason that certain records are filed and certain accounts are paid by the Army serial number and not by name.
Corps Areas
1st Corps Area – ME, VT, NH, MA, CT, RI
2nd Corps Area – NY, NJ, DE
3rd Corps Area – PA, MD, VA, DC
4th Corps Area – NC, SC, GA, FL, AL, MS, TN
5th Corps Area – OH, IN, KY, WV
6th Corps Area – IL, MI, WI
7th Corps Area – MO, KS, NB, CO, IA, MN, ND, SD, WY
8th Corps Area – AR, LA, TX, OK, NM
9th Corps Area - WA, OR, CA, ID, MT, NV, UT, AK
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TAG, IDENTIFICATION, M-1940 - Stock No. 74-T-60 official stocklist number + nomenclature, adopted 1940
NECKLACE & EXTENSION Stock No. 74-N-300, adopted 1943
Official stocklist number + nomenclature, length 40" (distance between 2 Dog Tags 1 ½"in) – in 1942, the first tag is to be suspended on a necklace 25" in length, while the second tag is to be fixed to a separate necklace extension not further than 2 ½" under the first one - first models were in cotton, plastic, nylon, rayon, the official metal necklace was only introduced in 1943 (with hooks & catches) the bead type (initially sold at PXs) quickly became popular and gradually replaced the 1943 issue, it was made out of 2 lengths of stainless steel, of approximately respectively 28" and 6" in length, easy and practical for general use 2" x 1 1/8".
DOG TAG 2' X 1-1/8" official dimensions, with notch at left (to position tag on the embossing machine) small outer rim, and hole (dia 1/8") for necklace
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SERIAL NUMBERS
Regular Army (1940) start with digit 1, followed by a second digit (indicating Corps Area/Service Cd) (there were 9 Corps Area for military administrative purposes, and 4 Army Areas for strategical military purposes) 14130598
National Guard (1940) start with digits 20, followed by a third digit (indicating Corps Area/Service Cd) 20417243
Draftees (1940) start with digit 3, followed by a second digit (indicating Corps Area/Service Cd) 31130734 (these were draftees called up by the Selective Training & Service Act)
Commissioned Officers (1921) start with prefix O, followed by hyphen + series of 2 > 6, even 7 digits (1940 starts with box of 23,000) O-57 O-3822 O-1170276
Warrant Officers (1942) start with prefix W, followed or not by hyphen + series of 7 digits, starting with 21 W-2118310
Flight Officers (1942) start with prefix T, followed by a series of digits T-6367
Army Specialist Corps (1942) start with prefix S, followed by a series of digits S-1038451
Army Nurse Corps (1921) start with prefix N, followed by a series of 6 digits (box of 700,000) N-782136
Hospital Dietitian + Physical Therapist (1942) HD start with prefix R, while PT start with prefix M, followed by a series of digits R..... M........
Contract Surgeon (1941) start with prefix CS, followed by a series of digits CS......
WAC (1943) start with prefix L (officer), L-918042, A (soldier) A-205333 and V (W.O.) V-704827, followed by a series of 6 digits, of which the first indicated the Service Cd
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Proud Daughter of Walter (Monday) Poniedzialek
540th Engineer Combat Regiment, 2833rd Bn, H&S Co, 4th Platoon
There's "No Bridge Too Far"