History behind Service Numbers

Ever thought why and how Service Numbers were derived and allocated. Well here is an explanation on everything you need to know on their allocation.

• Pre 1921 numbers were prefixed NZNF and were issued to NZ recruited regulars for service HMS PHILOMEL – Recruited 1914 and the highest known number was NZNF19.

• Numbers prefixed NZ were allocated to Royal Navy Reserve (NZ) men when recruitment commenced July 1904.

• Two distinct series of numbers were allocated by Australian Naval Station (RN) These were 551 – 699 and 1200 -1210.

• 38 men either NZNF or NZRNR served HMS PHILOMEL and qualified for 1914-15 star.

• A total of 100 NZ recruited men left New Zealand in October and November 1916 for service in the Royal Navy Volunteer Reserve (RNVR) (Motorboat section). On arrival in UK they were allocated MB numbers MB1820 – MB1877 and MB1906 – MB1948.

• Service Numbers commenced with the prefix NZD were issued from 1921

• No NZD519 was issued on 31 Jan 1931

• No NZD1629 was issued on 5 Sep 1939

• The first number issued without the ‘D’ was NZ3682 and this number was issued Feb 1942. The first number issued each year was as follows:

1945 – 10480
1946 – 11141
1947 – 11338
1948 – 11687
1949 – 12852
1950 – 13195
1951 – 13519
1952 – 13998
1953 – 14643
1954 – 14976
1955 – 15246
1956 – 15503
1957 – 15969
1958 – 16263
1959 – 16450
1960 – 16698
1961 – 16921
1962 – 17206
1963 – 17556
1964 – 17945
1965 – 18305
1966 – 18598
1969 – 19463

• Between 1945 and 1969 blocks of service numbers were issued as follows:

1948 11789 – 11890 Officers and Ratings
1948 11891 – 12026 Officer and loan RN/RM Ratings
1948 12118 – 12367 Issued to UK for frigates
1948/49 12552 – 12851 Issued to UK for frigates
1949 12990 – 13034 Issued to UK for RM Detachment
1950 13300 – 13349 Issued to UK
1951 13700 – 13900 Issued to UK
1952 14301 – 14500 Issued to UK
1956 15601 – 15800 Issued to UK
1957 16239 – 16255 Issued to Royal Marine Bandsman

• RN(NZ) 1 to 68 (at least) were issued to Artificers recruited for RN Service in early 1940

• NZ3682 joined Feb 1942 (This was the first number issued without the ‘D’)

• From about 1923/5 Ratings recruited into the Navy were given numbers prefixed ‘NZD’ indicating they were in the New Zealand Division of the Royal Navy. The numbers went from 100 up to about 9500 and were issued up until 1941 when we became the RNZN

• Pre WWII Service Numbers (usually below 1,000) with a single letter suffix were allocated to Serviceman of the Royal New Zealand Reserve. These numbers were prefixed with a letter denoting the Division the rating belonged to. Reserve ratings retained this number throughout even though they may have joined the regular force later on.

A/1600 – 1999 was for the Auckland Division
W/3000 – 3999 was for the Wellington Division
C/5000 – 5999 was for the Christchurch Division
O/7000 – 7999 was for the Otago Division

• In 1952 there was a Tri Service Agreement on the standardisation of Service Numbers and in 1955 the policy was implemented.  It was also agreed that personnel transferring between services were to retain their existing number.

• The allocation was as follows:

Navy (Male) 1 – 28499
Navy (Female) 28500 – 29999 (commenced 1 Jan 1967)
Army 30000 – 69999
Air Force 70000 – 99999
Navy (Non Reg) 100000 – 129999
Army (Non Reg) 130000 – 199999
Air (Non Reg) 200000 – 299999
For use on Introduction of National Service 300000 – 999999

• In 1942 ladies joining the WRNZNS were allocated sequential numbers commencing with 1. The highest known number is 1361 belonging to Penelope Fearn Smith who joined the Navy 25 Jan 1965.

• In 1971 when computers came in, the Prefix NZ was replaced with a single letter which was a “check letter” derived by the following mathematical formula.

A = divide the Service No by 23 and drop off the decimal parts (that is, keep the integer)
B = multiply A (the integer) by 23.
C = Subtract B from the Service NO
Alpha position = C+1 (this way we are guaranteed to never have position 0

So if your service number was 18812 the following calculation ensured you were allocated check letter ‘X’:

A = the integer of 18812 divided by 23 (817)
B = 817*23 (18791)
C= 18812-18791 (21)

The alphabet position = C+1 (22)

So discounting I,O,Z the alpha is X

Make sense well it did to someone.