The records in the Public Record Office are divided into classes. Each class represents a body of records related to a function of a governmental agency. Every class is given a class reference which is comprised of a lettercode of capital letters followed by a number (e.g. HO 1, RG 9, WO 97.) The classes are further subdivided into pieces.
Use the Current Guide to determine the classes of records that will be most useful to you in your research. Then turn to the Class Lists to obtain descriptions of the records and the full reference, including piece number, of the record that you wish to order from the Public Record Office. Below is a listing of Class lettercodes compiled from the 1996 version of the Current Guide.
| PRO Lettercode | Description |
| A | Alienation Office |
| AB | UK Atomic Energy Authority and its predecessors |
| ACT | Government Actuary's Department |
| ADM | Admiralty, Naval Forces, Royal Marines, Coastguard, and related bodies |
| AE | Royal Commission on Historical Manuscripts (England) |
| AF | Parliamentary Boundary Commissions for England and Wales |
| AH | Location of Offices Bureau |
| AIR | Air Ministry and successor, the Royal Air Force, and related bodies |
| AJ | Consumer Council |
| AK | Individual county courts |
| AM | Parliamentary Counsel's Office |
| AN | British Transport Commission, British Railways Board, and related bodies |
| AO | Auditors of the Imprest, Commissioners of Audit, Audit Office, Exchequer and Audit Department, National Audit Office and related bodies |
| AP | Irish Sailors and Soldiers Land Trust |
| AR | Wallace Collection |
| ASSI | Justices of assize, goal delivery, oyer and terminer, and nisi prius |
| AST | Unemployment assistance boards, Supplementary Benefits Commission, and related bodies |
| AT | Department of the Environment and related bodies |
| AVIA | Ministry of Aviation and successors, Air Registration Board, and related bodies |
| AW | British Airways and British Overseas Airways Corporation |
| AX | Local Government Boundary Commission for England |
| AY | Various research institutes |
| B | Commissioners of Bankrupts, the successor bankruptcy courts, and Court for the Relief of Insolvent Debtors |
| BA | Civil Service Department and related bodies |
| BC | Law Commission |
| BD | Welsh Office |
| BE | Iron and Steel Corporation of Great Britain, the Iron and Steel Board, and related bodies |
| BF | Pensions Appeal Tribunals |
| BH | Hudson Bay Company Archives |
| BJ | Meteorological Office |
| BK | National Dock Labour Corporation and Board |
| BL | Council on Tribunals |
| BM | Disabled Persons Employment Corporation Ltd., and Reemploy Ltd. |
| BN | Department of Health and Social Security and related bodies |
| BP | Royal Fine Art Commission |
| BR | British Transport Docks Board |
| BS | Defunct temporary bodies |
| BT | Board of Trade and successor and related bodies |
| BV | Parole Board |
| BW | British Council |
| BX | Coal Industry Social Welfare Organisation |
| BY | National Portrait Gallery |
| C | Chancery, and also Wardrobe, Household, Exchequer and various commissions |
| CAB | Cabinet Office, Committee of Imperial Defence, Central Statistical Office, and related bodies |
| CAOG | Crown Agents for Overseas Governments and Administrations |
| CB | National Playing Fields Association |
| CD | Cinematograph films |
| CE | British Museum |
| CF | National Health Service hospitals |
| CHAR | Charity Commissioners and Charity Commission |
| CHES | Palatinate of Chester, including the county of Flint |
| CJ | Northern Ireland Office |
| CK | Commission for Racial Equality, Race Relations Board, and Community Relations Commission |
| CL | Certification Office for Trade Unions and Employers' Associations |
| CM | Property Services Agency |
| CN | Photographs extracted from record classes |
| CO | Colonial Office, Commonwealth and Foreign and Commonwealth Offices, Empire Marketing Board, and related bodies |
| COAL | National Coal Board and related bodies |
| COPY | Copyright Office, Stationers' Hall |
| COU | National Parks Commission and the Countryside Commission |
| CP | Court of Common Pleas and other courts |
| CRES | Crown Estate Commissioners and their predecessors |
| CRIM | Central Criminal Court |
| CSC | Civil Service Commission |
| CSPR | Civil Service Pay Research Unit |
| CT | National Insurance Commissioners and the Social Security Commissioners |
| CUST | Boards of Customs, Excise, and Customs and Excise |
| CV | Value Added Tax Tribunals |
| CW | Advisory, Conciliation and Arbitration Service |
| CX | Price Commission |
| CY | Royal Commission on Environmental Pollution |
| D | Development Commission |
| DB | Council for National Academic Awards, and related bodies |
| DC | London Museum |
| DD | Local Government Boundary Commission for Wales |
| DEFE | Ministry of Defence, Chiefs of Staff Committee, and related bodies |
| DEL | High Court of Delegates |
| DF | British Museum (Natural History) |
| DG | International organisations |
| DH | British Library and the British Museum Library |
| DJ | Post Office Users National Council |
| DK | National Ports Council |
| DL | Duchy of Lancaster |
| DM | Occupational Pensions Board |
| DN | Public Health Laboratory Service Board |
| DO | Dominions Office, Commonwealth Relations and Foreign and Commonwealth Offices |
| DPP | Director of Public Prosecutions |
| DR | Civil Aviation Authority, including Air Registration Board |
| DSIR | Department of Scientific and Industrial Research and related bodies |
| DT | General Nursing Council for England and Wales |
| DURH | Palatinate of Durham |
| DV | Central Midwives Board |
| DW | Councils for the Training, and for the Education and Training, of Health Visitors |
| DX | Panel of Assessors for District Nurse Training |
| DY | Joint Board of Clinical Nursing Studies |
| E | Exchequer and Comptroller General of the Exchequer, and related bodies |
| EA | National Council, and Council, for Educational Technology |
| EB | Museums and Galleries Standing Commission, and the Museums and Galleries Commission |
| ECCL | Ecclesiastical Commission |
| ECG | Export Credit Guarantee Department |
| ED | Department of Education and Science, and related bodies |
| EF | Health and Safety Commission and Executive |
| EG | Department of Energy |
| EH | Pay Board |
| EJ | Schools Council for Curriculum and Examinations, and successor and related bodies |
| EL | Council for Encouragement of Music and the Arts, and the Arts Council of Great Britain |
| EM | Special Commissioners of Income Tax |
| EN | Imperial War Museum |
| EP | Advisory Council, and the Reviewing Committee on the Report of Works of Art |
| ER | Standing Civilian Courts |
| ES | Atomic Weapons Research Establishment |
| ET | Manpower Services Commission |
| EV | Science and Engineering Research Council |
| EW | Department of Economic Affairs |
| EXT | Extracts from documents in other classes |
| EY | Social Science Research Council and the Economic and Social Research Council |
| F | Forestry Commission and related bodies |
| FA | Office of Gas Supply |
| FB | Central Bureau for Educational Visits and Exchanges |
| FCO | Foreign and Commonwealth Office |
| FD | Medical Research Council |
| FEC | Forfeited Estates Commission |
| FG | National Economic Development Council and National Economic Development Office |
| FH | National Bus Company |
| FJ | Commission for the New Towns |
| FK | Office of the Secretary of State for Local Government and Regional Planning |
| FL | Adult Literacy Resource Agency and successors |
| FM | Historic Buildings and Monuments Commission for England (English Heritage) |
| FN | Pilotage Commission |
| FO | Foreign Office, the Foreign and Commonwealth Office, and related bodies |
| FP | Health Education Authority |
| FR | Legal Aid Board |
| FS | Registry of Friendly Societies |
| FT | Nature Conservancy Council |
| FV | Department of Trade and Industry (1970-1974) and successors |
| FW | National Curriculum Council |
| FY | Potato Marketing Board |
| GFM | Captured records of the German, Italian, and Japanese Governments |
| GIRO | National Giro |
| HA | Natural Environment Research Council |
| HB | Office of Electricity Regulation |
| HCA | High Court of Admiralty and colonial Vice-Admiralty courts |
| HD | Secret Intelligence Service |
| HE | English National Board for Nursing, Midwifery and Health Visiting |
| HF | Ministry of Technology |
| HK | Museums Association |
| HLG | Ministry of Housing and Local Government, and successor and related bodies |
| HMC | Royal Commission on Historical Manuscripts |
| HN | Central Computer and Telecommunications Agency and predecessors |
| HO | Home Office, Ministry of Home Security, and related bodies |
| HP | National Radiological Protection Board |
| HR | Marshall Aid Commemoration Commission |
| HS | Special Operations Executive |
| HT | Commission for Local Administration in England (Local Government Ombudsman) |
| HV | Crown Estate Paving Commission |
| HW | Government Communications Headquarters |
| HX | Civil Service Occupational Health Service and predecessors |
| HY | Intervention Board for Agricultural Produce |
| IND | Original indexes |
| INF | Central Office of Information |
| IR | Board of Stamps, Taxes, Excise, Stamps and Taxes, and Inland Revenue |
| J | Supreme Court of Judicature and related courts |
| JA | Department of Health (1988- ) |
| JB | Department of Social Security (1988- ) |
| JC | Office of Water Services (Ofwat) |
| JD | Monopolies and Restrictive Practices Commission, Monopolies Commission, and Monopolies and Mergers Commission |
| JE | Office of the National Lottery (Oflot) |
| JF | Department of Prices and Consumer Protection and successors |
| JH | Ministry of Land and Natural Resources and successor bodies |
| JK | Office of Her Majesty's Chief Inspector of Schools in Wales |
| JL | Curriculum Council for Wales and the Curriculum and Assessment Authority for Wales |
| JM | Further Education and Higher Education Funding Councils for Wales |
| JN | Committee on Standards in Public Life (Nolan Committee) |
| JP | Revenue Adjudicator's Office |
| JR | Office of the Rail Regulator |
| JS | Further Education Funding Council for England |
| JT | Local Government Commission for England |
| JUST | Itinerant justices and other court records |
| JV | Milk Marketing Board |
| JW | Metrication Board |
| JX | Office of the Data Protection Registrar |
| JY | Civil Service College |
| KA | Office of Passenger Rail Franchising |
| KB | Court of King's Bench and other courts |
| KC | School Examinations and Assessment Council |
| KD | Coal Authority |
| KE | Royal Air Force Museum |
| LAB | Departments responsible for labour and employment matters and related bodies |
| LAR | Land Registry |
| LC | Lord Chamberlain and other officers of the Royal Household, and the Clerk of the Recognizances |
| LCO | Lord Chancellor's Office and various legal commissions and committees |
| LO | Law Officers' Department |
| LR | Auditors of Land Revenue, The Surveyors General of Woods and Forest and others |
| LRRO | Office of Land Revenue Records and Enrolments and its predecessors and associated departments |
| LS | Lord Steward, the Board of Green Cloth and other officers of the Royal Household |
| LT | Lands Tribunal |
| MAF | Agriculture, Fisheries and Food Departments and related bodies |
| MEPO | Metropolitan Police Office |
| MH | Ministry of Health and successors, Local Government Boards and related bodies |
| MINT | Royal Mint |
| MONW | Royal Commission on Ancient and Historical Monuments in Wales and Monmouthshire |
| MPS | Maps, plans, and surveys from the British Transport Historical Records Office |
| MT | Transport departments and related bodies, and the London Passenger Transport Board |
| MUN | Ministry of Munitions and successors, including papers of David Lloyd George |
| NATS | Ministry of National Service |
| NDO | National Debt Office, and Pensions Commutations Board |
| NG | National Gallery |
| NIA | National Insurance Audit Department |
| NICO | National Incomes Commission |
| NMM | National Maritime Museum |
| NSC | National Savings Committee and Department, and the Post Office Savings Department |
| OBS | Obsolete lists and indexes |
| OD | Department of Technical Cooperation, and successive Overseas Development bodies |
| OS | Ordnance Survey of Great Britain |
| PALA | Palace Court |
| PC | Privy Council and Privy Council Office |
| PCAP | Judicial Committee of the Privy Council |
| PCOM | Prison Commission and Home Office Prison Department |
| PEV | Court of the Honour of Peveril |
| PIN | Ministry of Pensions and National Insurance, and related and successor bodies |
| PL | Palatinate of Lancaster |
| PMG | Paymaster General's Office, the Treasurer of the Navy, the Paymaster General of the Forces, and related bodies |
| POST | General Post Office |
| POWE | Ministry of Power, and related bodies |
| PP | Keeper of the Privy Purse |
| PREM | Prime Minister's Office |
| PRIS | King's Bench, Fleet, and Marshalsea prisons |
| PRO | Domestic records of Public Record Office, acquisitions by gift or deposit, and other collections and copies of records |
| PROB | Prerogative Court of Canterbury |
| PSO | Keeper of the Privy Seal [Privy Seal Office] |
| PT | Public Trustee Office |
| PWLB | Public Works Loan Board |
| QAB | Office of Queen Anne's Bounty, including Office of First Fruits and Tenths |
| RAIL | Pre-nationalization railway, canal and related companies, London Passenger Transport Board, and successors |
| RECO | Ministry of Reconstruction |
| REQ | Court of Requests |
| RG | General Register Office, Government Social Survey Department, and Office of Population Censuses and Surveys |
| RGO | Royal Greenwich Observatory |
| SC | Records of various departments, formerly called Special Collections |
| SO | Signet Office, and Home Office records relating to functions inherited from the Signet Office |
| SP | State Paper Office, including Secretaries of State up to 1782 |
| STAC | Court of Star Chamber |
| STAT | Stationery Office |
| SUPP | Ministry of Supply and successors, the Ordnance Board, and related bodies |
| T | Treasury, Chancellor of the Exchequer's Office, and Rating of Government Property Department |
| TG | Tate Gallery |
| TITH | Tithe Commission and successor bodies |
| TS | Treasury Solicitor and HM Procurator General's Department |
| UGC | University Grants Committee and Universities Funding Council |
| WALE | Records relating to Wales |
| WARD | Court of Wards and Liveries |
| WO | War Office, Armed Forces, Judge Advocate General, and related bodies |
| WORK | Works departments, and the Ancient Monuments Boards and Inspectorate |
| ZBOX | Unfinished and unpublished texts, calendars and finding aids held in the Public Record Office |
| ZHC | Publications of House of Commons, including some House of Lords |
| ZHL | Publications of House of Lords |
| ZJ | London Gazettes |
| ZLIB | British Transport Historical Records Office library |
| ZMAP | Maps and plans formerly held by the Public Record Office library |
| ZOS | Publications of the Ordnance Survey of Great Britain |
| ZPER | Periodicals held by British Transport Historical Records Office library |
| ZPSC | Publications and other materials held by British Transport Historical Records Office library |
Copyright © 1998-2006 Linda Jonas. All rights reserved.