| A&AEE | Aeroplane and Armament Experimental Establishment |
| A/Cdre | Air Commodore |
| AA | Anti-aircraft; Automobile Association; Architectural Association; Augustinians of the Assumption |
| AA&QMG | Assistant Adjutant and Quartermaster-General |
| AAA | Amateur Athletics Association; American Accounting Association |
| AAAC | Australian Army Air Corps |
| AAAS | American Association for the Advancement of Science |
| AAC | Army Air Corps |
| AACCA | Associate, Association of Certified and Corporate Accountants |
| AADip | Architectural Association Diploma |
| AAF | Auxiliary, Air Force |
| AAG | Assistant Adjutant-General |
| AAI | Associate, Chartered Auctioneers' and Estate Agents' Institute |
| AAMC | Australian Army Medical Corps |
| AASA | Associate, Australian Society of Accountants |
| AB | Bachelor of Arts (US); able-bodied, seaman |
| ABA | Amateur Boxing Association; Antiquarian Booksellers' Association; American Bar Association |
| ABC | Australian Broadcasting Commission; American Broadcasting Companies; Amateur Boxing Club; Associate, Birmingham Conservatoire |
| ABCC | Association of British Chambers of Commerce |
| ABRC | Advisory Board for the Research Councils |
| ABSA | Association for Business Sponsorship of the Arts |
| AC | Companion, Order of Australia; Ante Christum (before Christ) |
| ACA | Associate, Institute of Chartered Accountants |
| Acad | Academy |
| ACARD | Advisory Council for Applied Research and Development |
| ACAS | Advisory, Conciliation and Arbitration Service; Assistant Chief of the Air Staff |
| ACC | Association of County Councils; Anglican Consultative Council |
| ACCA | Associate Chartered Association of Certified Accountants |
| ACDS | Assistant Chief of Defence Staff |
| ACE | Association of Consulting Engineers; Member, Association of Conference Executives, |
| ACF | Army Cadet Force |
| ACFA | Army Cadet Force Association |
| ACGI | Associate, City and Guilds of London Institute |
| ACGS | Assistant Chief of the General Staff |
| ACIArb | Associate, Chartered Institute of Arbitrators |
| ACIB | Associate, Chartered Institute of Bankers |
| ACII | Associate, Chartered Insurance Institute |
| ACIS | Associate, Institute of chartered Secretaries and Administrators (formerly Chartered Institute of Secretaries) |
| ACM | Association of Computing Machinery |
| ACMA | Associate, Chartered Institute of Management Accountants (formerly Institute of and Management Accountants) |
| ACNS | Assistant Chief of Naval Staff |
| ACOS | Assistant Chief of Staff |
| ACOST | Advisory Council on Science and Technology |
| ACP | Association of Clinical Pathologists; Associate, College of Preceptors; African/Caribbean/Pacific |
| ACPO | Association of Chief Police Officers |
| ACSM | Associate, Camborne School of Mines. |
| ACT | Australian Capital Territory; Australian College of Theology; Associate, College of Toohnology; Association of Corporate Treasurers |
| Actg | Acting |
| ACTT | Association of Cinematograph, Television and Allied Technicians |
| ACU | Association of Commonwealth Universities |
| ACWA | Associate, Institute of Cost and Works Accountants |
| AD | Dame of the Order of Australia: Anno Domini (in the year of the Lord); Air Defence |
| ADC | Aide-de-Camp |
| Addl | Additional |
| ADGB | Air Defence of Great Britain |
| Adj | Adjutant |
| ADM | Advanced Diploma in Midwifery |
| Admin | Administration |
| Adml | Admiral |
| Admlty | Admiralty |
| ADMS | Assistant Director of Medical Services |
| advsr/y | adviser/advisory |
| AE | Air Efficiency Award |
| AEA | Air Efficiency Award; Atomic Energy Authority |
| AEC | Agriculture Executive Council; Army Educational Corps; Atomic Energy Commission |
| AEEU | Amalgamated Engineering and Electrical Union |
| AEF | Amalgamated Union of Engineering and Foundry Workers; American Expeditionary Forces |
| AEI | Associated Electrical Industries |
| AEM | Air Efficiency Medal |
| AER | Army Emergency Reserve |
| AERE | Atomic Energy Research Establishment (Harwell) |
| AEU | Amalgamated Engineering Union |
| AFA | Amateur Football Alliance |
| AFBPsS | Associate Fellow, British Psychological Society |
| AFC | Air Force Cross; Association Football Club |
| AFCENT | Allied Forces in Central Europe |
| AFF | Agriculture, Fisheries and Food (see also MAFF) |
| Affrs | Affairs |
| AFHQ | Allied Force Headquarters |
| AFICD | Associate Fellow, Institute of Civil Defence |
| AFRAeS | Associate Fellow, Royal Aeronautical Society |
| AFRC | Agricultural and Food Research Council |
| AFV | Armoured Fighting Vehicles |
| AG | Attorney-General |
| AGRA | Army Group Royal Artillery; Association of Genealogists and Record Agents |
| AGSM | Associate, Guildhall School of Music and Drama; Australian Graduate School of Management |
| Agy | Agency |
| AHA | Area Health Authority; American Hospitals Association; Associate, Institute of Health Service Administrators |
| AHQ | Army Headquarters |
| AHSM | Associate, Institute of Health Services Management |
| AIAgrE | Associate, Institution of Agricultural Engineers |
| AIB | Associate, Institute of Bankers |
| AIC | Agricultural Improvement Council; Associate, Institute of Chemistry |
| AICA | Associate Member, Commonwealth Institute of Accountants; Association Intemationale des Critiques d'Art |
| AICE | Associate, Institution of Civil Engineers |
| AICS | Associate, Institute of Chartered Shipbrokers |
| AIDS | Acquired Immune Deficiency Syndrome |
| AIEE | Associate, Institution of Electrical Engineers |
| AIF | Australian Imperial Forces |
| AIG | Adjutant-Inspector-General |
| AIIA | Associate, Insurance Institute of America; Associate, Indian Institute of Architects |
| AIIMR | Associate, Institute of Investment Management and Research |
| AILA | Associate, Institute of Landscape Architects |
| AIM | Associate, Institution of Metallurgists; Australian Institute of Management |
| AIMarE | Associate, Institute of Marine Engineers |
| AIME | American Institute of Mechanical Engineers |
| AIMSW | Associate, Institute of Medical Social Work |
| AInstP | Associate, Institute of Physics |
| AK | Knight, Order of Australia; Alaska |
| AKC | Associate, King's College London, |
| ALA | Associate, Library Association; Association of London Authorities |
| ALAM | Associate, London Academy of Music and Dramatic Art |
| ALCM | Associate, London College of Music |
| ALFSEA | Allied Land Forces South-East Asia |
| ALI | Argyll Light Infantry; Associate, Landscape Institute |
| ALICE | Autistic and Language Impaired Children's Education |
| AM | Albert Medal; Member, Order of Australia; Master of Arts (US); Alpes Maritimes |
| AMA | Association of Metropolitan Authorities; Assistant Masters Association; Associate, Museums Association; Australian Medical Association |
| Amb | Ambassador |
| AMBIM | Associate Member, British Institute of Management |
| AMC | Association of Municipal Corporations |
| AMCT | Associate, Manchester College of Technology |
| AMF | Australian Military Forces |
| AMICE | Associate Member, Institution of Civil Engineers |
| AMIChemE | Associate Member, Institution of Chemical Engineers |
| AMIE(Aust) | Associate Member, Institution of Engineers, Australia |
| AMIEE | Associate Member, Institution of Electrical Engineers |
| AMIMechE | Associate Member, Institution of Mechanical Engineers |
| AMIMM | Associate Member, Institution of Mining and Metallurgy |
| AMInstCE | Associate Member, Institution of Civil Engineers |
| AMInstTA | Associate Member, Institute of Traffic Administration |
| AMINucE | Associate Member, Institution of Nuclear Engineers |
| AMIStructE | Associate Member, Institution of Structural Engineers |
| AMNZIE | Associate Member New Zealand Institute of Engineers |
| AMP | Advanced Management Program; Air Member for Personnel |
| AMRINA | Associate Member, Royal Institution of Naval Architects |
| AMS | Assistant Military Secretary; Army Medical Services |
| Anon | Anonymously |
| ANU | Australian National University |
| Anzac | Australian and New Zealand Army Corps |
| AO | Officer, Order of Australia; Air Officer |
| AOA | Air Officer in charge of Administration |
| AOC | Air Officer Commanding |
| AOD | Army Ordnance Department |
| APD | Army Pay Department |
| APEX | Association of Professional, Executive, Clerical and Computer Staff |
| APM | Assistant Provost Marshal |
| APMI | Associate, Pensions Management Institute |
| apptd | appointed |
| AQ | Administration and Quartering |
| AQG/AQMG | Assistant Quartermaster-General |
| AR | Associated Rediffusion (Television); Arkansas |
| ARA | Associate, Royal Academy |
| ARAeS | Associate, Royal Aeronautical Society |
| ARAIA | Associate, Royal Australian Institute of Architects |
| ARAM | Associate, Royal Academy of Music |
| ARBA | Associate, Royal Society of British Artists |
| ARBS | Associate, Royal Society of British Sculptors |
| ARC | Architects' Registration Council; Agricultural Research Council; Aeronautical Research Council |
| ARCA | Associate, Royal College of Art; Associate, Royal Canadian Academy |
| ARCM | Associate, Royal College of Music |
| ARCO | Associate, Royal College of Organists |
| ARCS | Associate, Royal College of Science |
| ARCUK | Architects' Registration Council of the United Kingdom |
| ARCVS | Associate, Royal College of Veterinary Surgeons |
| ARE | Associate, Royal Society of Painter-Printmakers (formerly of Painter-Etchers and Engravers); Arab Republic of Egypt; Admiralty Research Establishment |
| ARIAS | Associate, Royal Incorporation of Architects in Scotland |
| ARIBA | Associate, Royal Institute of British Architects |
| ARIC | Associate, Royal Institute of Chemistry |
| ARICS | Professional Associate, Royal Institution of Chartered Surveyors |
| ARMS | Associate, Royal Society of Miniature Painters |
| ARP | Air Raid Precautions |
| ARPS | Associate, Royal Photographic Society |
| ARRC | Associate, Royal Red Cross |
| ARSA | Associate, Royal Scottish Academy |
| ARSM | Associate, Royal School of Mines |
| ASA | Associate Member, Society of Actuaries; Associate of Society of Actuaries (US); Australian Society of Accountants; Army Sailing Association; Advertising Standards Authority |
| ASC | Administrative Staff College, Henley; Army Service Corps |
| ASE | Amalgamated Society of Engineers; Association for Science Education |
| ASEAN | Association of South East Asian Nations |
| ASH | Action on Smoking and Health |
| Assist | Assistant |
| Assoc | Association |
| Assur | Assurance |
| ASTC | Administrative Service Training Course |
| ASTMS | Association of Scientific, Technical and Managerial Staffs |
| ATA | Air Transport Auxiliary |
| ATC | Air Training Corps; Art Teacher's Certificate |
| ATCL | Associate, Trinity College of Music, London |
| ATI | Associate, Textile Institute |
| ATO | Ammunition Technical Officer |
| ATS | Auxiliary Territorial Service |
| attd | attached |
| ATV | Association TeleVision |
| AUEW | Amalgamated Union of Engineering Workers |
| AUT | Association of University Teachers |
| Aux | Auxiliary |
| Ave | Avenue |
| AVR | Army Volunteer Reserve |
| AWAS | Australian Womens' Army Service |
| AZ | Arizona |