An interesting look at how your Royal Navy Official Number came to be

In general, prior to the year 1853 and when the country was not at war, all ratings of the Royal Navy were casually employed, that is, "signed on" for one commission at a time. However, back in 1832 an exception to the rule occurred when seamen gunners only were offered renewable 5 or 7 year engagements.  They served in their ships on ships-book-numbers [something we are all familiar with] but had no pan-Navy numbering system.

During 1853 Continuous Service Engagements were introduced which allowed the men to complete time for a pension, just as we do now.  This date is very important because until 1853, Britain had no "standing navy" to call upon, and all but a few were really part timers.  Despite all the learned writings about King Alfred and  King Henry VIII starting the navy, the navy we think of today is only just over 150 years old, and I joined in 1953 in the navy's centenary year.

After the 13th June 1853, most of the ratings already serving and those about to join, had the option to "sign on" and all who did were given a number known  as  a C.S.No - continuous service number.

Not all were allowed to "sign on".  By circular number 121 of the 14th June 1853 which was to remain extant for twenty years until 1873, men with the following [daymen] rating were ineligible: seamen's schoolmaster, ship's cook, sick-berth attendant, all servants {officers and warrant officers had servants}, musicians, bandsmen, butchers, barbers, tailors, ship's steward's assistant, cook's mate and ship's steward's boy. However, inside the twenty year period mentioned above expiring in 1873, several of the rates mentioned here were recategorised to 'domestic rates' and were allowed to "sign on" after the change.

Like the majority of 'administrative procedures' brought into the navy, all but a few of them had to be re-thought through to put right the many errors and flaws which could have been avoided by better research.  The Continuous Service numbering system was no exception, and some fifteen years on in 1867 the numbers looked like this:-

from the start in 1853, numbers ran from 1 to 40,000, and it took six years to get those men -
from 1859, the number chain changed to 1A to 40,000A, which lasted for the next eight years -
and from 1867, the number chain changed to 1B to 21800B, which lasted until the end of the twenty years period, i.e., in 1873.

One can assume that during this twenty year period, over 100,000 men "signed on".

On the 1st January 1873, all men in the navy, CS men and CS debarred men, were given an OFFICIAL NUMBER. The 'standing navy' now had a great number of men on its books, and greater care in a new series of numbering was needed especially if confusion with the old pre 1873 numbering system was to be avoided. To achieve this, O.N's., had to be, as a minimum, 40,001 transcending all previously used numbers.  These two pictures come from my web page covering over 132 years of naval service in my family [click HERE to view it]. They are both taken from Robert Turrell's  SC's, the first one showing his new Official Number as being 41243 gt10 and the date he took on for CS which was 1 July 1870 and the second shows his original CS Number as being 11469A Click to enlarge.

On the 1st January 1894, the official numbering  system for all ratings entering the Service became sub-specialised and six blocks of numbers were assigned to six different BRANCHES of ratings.



Seamen and Communicators

178001 to 240500

Engine room Artificers

268001 to 273000


276001 to 313000

Artisans and Miscellaneous

340001 to 348000

Sick Bay staff and Ships Police [RPO'S]

350001 to 352000

Officers Stewards, Cooks and Boy Servants

353001 to 366450

However, by 1907 there was a danger of the blocks of numbers over spilling into other blocks, so from the 1st January 1908 [which lasted until 1925] the Admiralty decided to add a PREFIX to a new series of numbers. They used the letters J, K, L and M, where 'J' became executive [seamen and communicators], 'K' for Stokers, 'L' for Cooks and Stewards and 'M' for the other three Branches listed.

In 1925, Admiralty introduced a major change in pay scales, so that those joining from this year would enter on a lower pay scale than those who were already serving whose pay would remain the same.   To be able to readily recognise the men on the Lower pay scale from those on the Upper scale, they changed the Official Number system. At the time of the change, the official numbers of the four lettered prefix systems had reach J115433; K66973; L15101 and M39555, so to differentiate, they started yet another series of numbers and added the letter 'X'.


UPPER PAY SCALE PRE 25th October 1925
[Those already serving]

LOWER PAY SCALE POST 25th October 1925
[Those joining on or after this date]

Seamen and Communicators

J...... to J115433

JX commencing with 125001

Stokers K66973

KX commencing with 75001

Officers Cooks and Stewards L15101

LX commencing with 20001

All others M39555

MX commencing with 45001

The 1931 pay review which led to the Invergordon lower deck junior rates mutiny, issued under AFO 2239/31, added the dreaded 'X' to all official numbers, taking the 1919 pay rates of the single letter prefix official numbers down to the 1925 lower level ; those already with the 'X' didn't suffer - their pay stayed the same. So, taking the seamen and communications branch for example, all ratings had a JX prefix to their official numbers.

The next change to official numbers came in 1934 and involved the addition of a third letter in front of the number. Although other letters were used [L = Lee-on-Solent, for Fleet Air Arm - E for Maltese LEP'S {locally entered personnel} and others], the main letters were C, D and P representing Chatham, Devonport and Portsmouth respectively.  After this change, an observer could ascertain from a mans official number his Port Division [Welfare Authority] and in the case of the J and K, his Branch, but the L and M had to be guessed at especially the M which covered many Branches and sub-Branches. The actual number remained a problem because it was possible to have two men in the service with exactly the same number but different prefixes.  Another change was required.

In 1943 when the majority of the Navy were pre-occupied with fighting the war, the administrators decided to introduce the change. Commencing on the 1st April a common bank of numbers would be used for all entries in the RN commencing with the number 500000. The prefix J,K,L and M, plus the letter F for Fleet Air Arm would remain for all normal engagements, and the letters SS = seamen and communicators and some stokers, SK = other stokers, SL = officers cooks and stewards, SM = ERA's and miscellaneous branches, SF = fleet air arm, were introduced for special service engagements. Thus, a man serving a twelve-year engagement could be PJX ******, whereas a man serving seven years in the RN and a further five years on the books of the RNR {the same twelve years} could be PSSX******.

Coronation year, 1953 brought two more changes. The letter 'X' was dropped for all new entries after the 1st April, and a new number series was adopted starting with 925000 onwards.  I joined just 5 months later on the 13th October 1953 so my number was J930735: note that the P for Portsmouth in my case, was not added until we were assigned a home port towards the very end of our fifteen months training at HMS Ganges. If your calculator is working properly, that should tell you that I was number 5735 recruit on the new system, and isn't it uncanny that the last three figures match the last three figures of my official number?

1955 saw the introduction promulgated through AFO 1293/55 of a computerised pro forma which helped the administrators but didn't affect the men or their official numbers.

Home Port drafting, conducted from the three main barracks in Chatham, Devonport and Portsmouth plus Lee-on-Solent for the fleet air arm, ceased in 1957 when central drafting took over, rendering the need for the Port Division prefix letter obsolete.  Nevertheless it was kept to denote the mans "selected" depot. From then on, central drafting was carried out from the sleepy Surrey town of Haslemere {named HMS Centurion by DCI [RN] [U] 1283/64} later to be supplanted by HMS Centurion at Gosport Hampshire.

Administrators, not wanting us to think that they were under employed avoided boredom by introducing another system on the 1st April 1959. All recruits on or after this date used the number series 050001 and upwards with just a single letter prefix denoting their selected Welfare Authority now to include HMS Cochrane in Rosyth Scotland, along with the existing south of England old home ports.

Then, for those still serving with official numbers like PJ etc, a change was made, for computer reasons, whereby the welfare authority prefix letter would cease leaving just the J in front of the existing number but adding a single letter suffix [the computer verification code]: my number for example became J930735X and that is the one I left with in July 1983.

Officers {although not part of my story}, hitherto without any form of official number, were given one with a single prefix letter of 'C', meaning, I would think, 'commissioned'.

That then gentlemen, is how the officials made you official as a Royal sailor. Even today, long after leaving the navy, your number is still required by researchers into records held either in HMS Centurion or the Public Records Office [PRO] at Kew, and it was your official number which gave you your service pension number - if you receive one!   If, and I trust it will not happen, you ever fall upon hard times and wish to seek the assistance of SSAFA, the RNBT, the Royal British Legion etc, you will need to quote your official number.  So remember, after your National Insurance Number, it is still the second most important number in your life's story.

Happy days!! However see the FOOTNOTE added a few years after this page was written.

P.S. Anecdotal evidence adds spice to my stories, so if you have something of consequence [no trivia please] to add, then do not hesitate in sending it to me.  The following snippet was sent to me by a grandee of the Communications Branch, Dennis Alderson.

On the subject of Official Numbers, which I found most interesting, I wonder how many different Official Numbers have been held during one's service.
I seem to remember that I have had five!
Originally (being a Londoner) I was a Chatham rating on emerging from Ganges,  thus I was C/JX 819724 (it is still imprinted on the bottom of my kit bag). Then I changed to Pompey (can't remember why) and became P/JX 819724.  Whilst serving at Whitehall Wireless (1954-1956) they brought out the 7 and 5 short service commission and I once again changed, this time to  SSX 819724 (I don't think there was a prefix to SSX).  After I changed my mind about Short Service and having signed for 12 years it changed back to P/JX 819724. At some stage I became just J 819724 C, which remained right up to leaving Mercury as an FCRS in November 1975.  The last change made my Official Number C 025055 A!

You should immediately recognise Dennis's last sentence from my pen ultimate paragraph above, because of the prefix 'C'. Dennis became a Lieutenant R.N., in the Careers Service, and became the "press-ganger" {no, not really - only kidding Dennis} for part of the Midlands based in Derby.

FOOTNOTE dated 24th April 2013:  The Ganges website which closed down on the 23rd April 2013 making way for a new site, had a section on members showing official numbers. Not only were there several entries purposely designed to ridicule the webmaster who had worked hard to set things up, but by being flippant, childish and destructive, the use of the list of Members cannot be used for any serious or authoritative  purpose. This I see has, to some extent, been carried over the the new web site. We can never stop louts destroying things but we should be able to get boys to follow the rules to write down a few simple figures, although it is possible that these offenders were GC Class and therefore possibly dyslexic or even innumerate and illiterate?  These were boys for they had joined before the watershed on 1956 which introduced juniors to supplant the rate of boy seaman etc. The following personnel still persist in using a letter 'X' in the prefix of their official numbers even though in every case, these numbers are greater than 925000.

Colin BROWNE 926338, Rodney CARPENTER 936525, Peter CHANDLER 942151, Gerard COGHLAN 934082,  Denis GLASSETT 926045,  William HENLEY 926040, Michael HIBBEARD 926318,  Charles HORSMAN 938005,  John LADD 934234,  Ray LAMBERT 926036,  John WALTON 934384 and Andrew WRIGHT 942420.