| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
| A | Germany | 
      | 
      | 
      | 
      | 
    AA-AL | United States | 
|   | 
    AM-AO | Spain | 
| AP-AS | Pakistan | 
| AT-AW | India | 
| AX | Australia | 
| AY-AZ | Argentina | 
| B | Great Britain | 
      | 
      | 
      | 
      | 
    B | China | 
|   | 
      | 
    CA-CE | Chile | 
| CB | Bolivia | 
| CC | Cuba | 
|   | 
| CE | Chile | 
|   | 
    CF-CK | Canada | 
| CL-CM | Cuba | 
| CN | Morocco | 
    CN | Morocco | 
| CO-CP | Chile | 
      | 
    CO | Cuba | 
| CP-CR | Portugal | 
    CP | Bolivia | 
| CQ | Monaco | 
      | 
    CQ-CR | Portuguese colonies | 
    CQ-CU | Portugal | 
| CR-CT | Portugal | 
    CR | Portuguese colonies | 
|   | 
    CS-CU | Portugal | 
|   | 
    CU-CV | Roumania | 
| CV | Roumania | 
    CV | Roumania | 
    CV-CX | Uruguay | 
| CW | Uruguay | 
    CW-CX | Uruguay | 
|   | 
      | 
|   | 
    CY-CZ | Canada | 
| CZ | Monaco | 
| D | Germany | 
    DA-DM | Germany | 
    D | Germany | 
    DA-DM | Germany | 
    DA-DT | Germany | 
    DA-DR | West Germany | 
|   | 
    DN-DQ | Belgian Congo | 
| DR-DT | Belarus | 
| DS-DT | South Korea | 
| DU-DZ | Philippines | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
| EA-EG | Spain | 
    EA-EH | Spain | 
|   | 
      | 
      | 
| EI | Ireland | 
    EI-EJ | Ireland | 
|   | 
      | 
| EK | Japan | 
    EK | Soviet | 
    EK | Armenia | 
| EL | Liberia | 
|   | 
      | 
    EM-EO | Japan | 
    EM-EO | Soviet | 
    EM-EO | Ukraine | 
| EP-EQ | Persia > Iran | 
| EQ | Equador | 
      | 
|   | 
      | 
    ER | Japan | 
    ER | Soviet | 
    ER-ES | Soviet | 
    ER | Moldova | 
| ES | Estonia | 
    ES | Estonia | 
| ET | Ethiopia | 
|   | 
      | 
    EU-EY | Japan | 
    EU-EZ | Soviet | 
    EU-EW | Belarus | 
| EX-EZ | Soviet | 
    EX | Kyrgys | 
| EY | Tajikistan | 
| EZ | Zaar | 
    EZ | Geramny | 
    EZ | Turkmenistan | 
| F | France | 
| G | Great Britain | 
| HA-HF | Austria-Hungary and Bosnia-Herzegovina | 
    HA-HE | Austria | 
    HA | Hangary | 
| HB | Switzerland | 
| HC | Ecuador | 
    HC-HD | Ecuador | 
|   | 
      | 
| HE | Switzerland | 
|   | 
    HF | Poland | 
| HG-HH | Siam | 
    HG | Japan | 
    HG | Hungary | 
| HH | Haiti | 
|   | 
    HI | Dominica | 
| HJ | Columbia | 
    HJ-HK | Columbia | 
|   | 
|   | 
      | 
    HL-HM | Japan | 
    HL-HM | Chosen > South Korea | 
    HL | South Korea | 
| HM | North Korea | 
| HN | Iraq | 
| HO-HP | Panama | 
| HQ-HR | Honduras | 
| HR | Honduras | 
| HS | Siam > Thai | 
|   | 
      | 
      | 
    HT | Nicaragua | 
| HU | Salvador > El Salvador | 
| HV | Vatican | 
|   | 
    HW-HY | France | 
| HZ | Hedjaz > Saudi Arabia | 
| I | Italy | 
    IA-IM | Italy | 
    I | Italy | 
|   | 
| J | Japan | 
    JA-JM | Japan | 
    J | Japan | 
    JA-JS | Japan | 
|   | 
| JT-JV | Mongol | 
| JW-JX | Norway | 
|   | 
    JY | Jordan | 
| JZ | Dutch New Guinea > Indonesia | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
| KA-KC | Germany | 
    K | United States | 
| KD-KZ | United States | 
| LA-LH | Norway | 
    LA-LM | Norway | 
    LA-LN | Norway | 
| LI-LR | Argentine | 
|   | 
| LO-LV | Argentine | 
    LO-LW | Argentine | 
| LP-LQ | Argentine | 
| LR | Liberia | 
|   | 
      | 
| LV | Guatemara | 
| LW-LX | Bulgaria | 
      | 
| LX-LZ | Bulgaria | 
    LX | Luxembourg | 
| LY | Hedjaz | 
    LY | Lithuania | 
| LZ | Czechslovakia | 
    LZ | Bulgaria | 
| M | Great Britain | 
| N | United States | 
|   | 
    OA-OE | Belgium | 
    OA-OB | Peru | 
    OA-OC | Peru | 
|   | 
|   | 
    OD | Syrian-Lebanon > Lebanon | 
| OE | Austria | 
|   | 
    OF-OH | Finland | 
    OF-OJ | Finland | 
| OG-OM | Austria-Hungary and Bosnia-Herzegovina | 
| OH | Finland | 
|   | 
      | 
| OK | Czechslovakia | 
    OK-OM | Czechslovakia | 
    OK-OL | Czech | 
|   | 
      | 
| OM | Slovak | 
| ON-OT | Belgium | 
    ON-OR | Denmark | 
    ON-OT | Belgium | 
|   | 
| OU-OZ | Denmark | 
    OU | Peru | 
    OU-OZ | Denmark | 
|   | 
| PA-PI | Netherlands | 
    PA-PG | Brazil | 
    PA-PI | Netherlands | 
|   | 
| PJA-PJM | Curacao (Dutch) | 
    PJ | Curacao > Dutch Antilles | 
| PJN-PJZ | Surinam (Dutch) | 
| PK-PM | Dutch East Indies | 
    PK-PO | Dutch Indies > Indonesia | 
|   | 
| PP | Poland | 
    PP-PY | Brazil | 
|   | 
| PT-PZ | Netherlands | 
| PZ | Surinam | 
| Q | Reserved for code abbreviations | 
| R | Russia | 
    RA-RG | Russia | 
    RA-RQ | Soviet | 
    R | Soviet > Russia | 
|   | 
|   | 
| RV | Persia | 
|   | 
| RX | Panama | 
| RY | Lithuania | 
|   | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
| SA-SM | Sweden | 
| SN-ST | Brazil | 
    SN | Greece | 
      | 
      | 
    SN-SR | Poland | 
|   | 
    SO-SR | Poland | 
| SP | Panama | 
    SP-SR | Poland | 
|   | 
|   | 
      | 
    SS-SU | Egypt | 
    SSA-SSM | Egypt | 
| SSN-ST | Sudan | 
| ST-SU | Egypt | 
| SU | Egypt | 
    SU | Egypt | 
    SU | Egypt | 
| SV-SZ | Greece | 
    SV-SZ | Greece | 
| TA-TM | Turkey | 
    TA-TB | Turkey | 
    TA-TC | Turkey | 
|   | 
|   | 
      | 
    TD | Guatemala | 
| TE | Costa Rica | 
| TF | Iceland | 
| TG | Guatemala | 
|   | 
      | 
    TH | France | 
| TI | Costa Rica | 
|   | 
      | 
    TJ-TZ | France | 
    TJ-TR | France | 
    TJ | Cameroon | 
| TK-TZ | French colonies | 
    TK | France | 
| TL | Central Africa | 
| TM | France | 
|   | 
    TN | Congo | 
| TO-TQ | France | 
| TR | Gabon | 
| TS | Saar | 
    TSA-TSM | Tunisia | 
    TS | Tunisia | 
| TSN-TZ | France | 
|   | 
    TT | Chad | 
| TU | Cote d'Ivoire | 
| TV-TX | France | 
| TY | Benan | 
| TZ | Mali | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
| UA-UM | France | 
      | 
      | 
    U | Soviet | 
    UA-UQ | Soviet UA-UI,UJ-UM,UN-UQ | 
    UA-UI | Russia | 
| UH | Hedjaz | 
| UI-UK | Dutch Indies | 
| UJ-UM | Uzbekistan | 
| UL | Luxembourg | 
|   | 
| UN-UZ | Austria-Hungary and Bosnia-Herzegovina | 
    UN | Serbia, Croatia, Slovenia | 
    UN-UQ | Kazakhstan | 
| UO | Austria | 
|   | 
| UR-UT | Ukraine | 
    UR-UZ | Ukraine | 
| UU-UZ | Soviet | 
| VA-VG | Canada (British) | 
    VA-VC | Finland | 
    VA-VG | Canada | 
|   | 
| VH-VK | Australian Federation (British) | 
    VH-VM | Australia | 
    VH-VN | Australia | 
| VL-VM | New Zealand (British) | 
| VN | South African Union (British) | 
      | 
      | 
| VO | Newfoundland (British) | 
    VO | Newfoundland > Canada | 
| VP-VS | British colonies not autonomous | 
    VP-VS | British colonies not autonomous > Great Britain | 
    VP-VQ | Great Britain | 
| VR | China | 
| VS | Great Britain | 
| VT-VW | British India | 
    VT-VW | British India > India | 
|   | 
      | 
    VX-VY | Canada | 
|   | 
    VZ | Australia | 
| W | United States | 
| XA-XC | Mexico | 
    XA-XE | Mexico | 
    XA-XF | Mexico | 
    XA-XI | Mexico | 
|   | 
|   | 
| XG-XU | China | 
| XH | Honduras | 
|   | 
| XJ-XO | Canada | 
| XN | China | 
|   | 
| XP | Denmark | 
| XQ-XR | Chile | 
| XS | Yugoslavia | 
    XS | China | 
|   | 
    XT-XW | France | 
    XT | France | 
    XT | Haute Volta > Burkina Faso | 
| XU | Cambodia | 
|   | 
      | 
    XV-XW | Frace | 
    XV | Viet Nam | 
| XW | Laos | 
| XX | Portuguese colonies > Portugal | 
| XY-XZ | British India > Burma > Myanmer | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve | 
|   | 
      | 
    YA | Afganistan | 
|   | 
    YB-YH | Dutch Indies > Indonesia | 
| YH | New Hebrides | 
| YI | Iraq | 
|   | 
    YJ | New Hebrides > Vanuatu | 
|   | 
    YK | Soviet | 
    YK | Syria | 
| YL | Latvia | 
    YL | Soviet | 
    YL | Latvia | 
| YM | Danzig | 
    YM | Turkey | 
| YN | Nicaragua | 
|   | 
    YO-YR | Romania | 
| YS | Salvador > El Salvador | 
|   | 
    YT-YU | Yugoslavia | 
| YV | Venezuela | 
    YV-YW | Venezuela | 
    YV-YY | Venezuela | 
|   | 
|   | 
    YY-YZ | Soviet | 
| YZ | Yugoslavia | 
    YZ | Serbia and Montenegro | 
|   | 
    Z | Great Britain | 
    ZA | Albania | 
|   | 
    ZB-ZJ | British colonies > Great Britain | 
| ZK-ZM | New Zealand | 
|   | 
      | 
    ZN-ZO | British colonies > Great Britain | 
| ZP | Paraguay | 
|   | 
      | 
    ZQ | British colonies > Great Britain | 
| ZR-ZU | South Africa | 
| ZS-ZU | South Africa | 
|   | 
      | 
    ZV-ZZ | Brazil | 
| After 1912 London | 1920 Washington (Provisional) | 1927 Washington | 1932 Madrid | 1938 Cairo | 1947 Atlantic City | 1959 Geneve | 1979 Geneve | After 1979 Geneve |