| Inscription | Country | Years | #Issued |
| Idar State | India: Idar(sta) | 1939-44 | 6 |
| Ifni | Ifni | 1941-68 | 200 |
| Ile de la Reunion | France: Reunion(isl) | 1852 | 2 |
| Iles des Sourds | Bogus | ||
| Imperial Chinese Post | China | 1897-10 | |
| Imperiales de Coree | Korea | 1903 | 15 |
| Imperial Japanese Post | Japan | 1876-96 | 45 |
| Imperial Korean Post | Korea | 1900-01 | 20 |
| Imperio Colonial Portugues | Portuguese Africa | 1945 | 9 |
| Impto da Guerra | Spain (War Tax) | 1874-97 | 30 |
| Impuesto da Guerra | Spain (War Tax) | 1874-97 | 30 |
| Inde Francais | French India | 1929 | |
| India | India | 1854- | 1800 |
| India Port | Portuguese India | 1871-83 | 70 |
| India Portuguesa | Portuguese India | 1877-86 | 120 |
| Indochine | Indo-China | 1892-1946 | 440 |
| Indonesia | Netherlands Indies | 1948-49 | 40 |
| Indore State | India: Indore(sta) | 1904-47 | 40 |
| Inhambane | Mozambique: Inhambane(adm) | 1895-1917 | 100 |
| Instruccion (oval) | Venezuela | 1893 | 8 |
| Iran | Iran | 1949- | 1500 |
| Iraq | Iraq | 1923- | 1700 |
| Irian Barat | West Irian | 1963-70 | 60 |
| Island | Iceland | 1873- | 700 |
| Island Frimerki | Iceland | ||
| Islas Galapagos | Ecuador: Galapagos Islands(isl) | 1957-59 | 7 |
| Isle of Man | Great Britain: Isle of Man(isl) | 1973- | 320 |
| Isole Jonie | Great Britain: Ionian Islands(isl) | 1941 | 10 |
| Isole Italiane dell'Egeo | Italy: Aegean Islands(isl) | 1930-40 | 150 |
| Israel | Israel | 1948- | 1000 |
| Istria | Bogus | ||
| Ita Karjala | Karelia? | 1922-43 | 40 |
| Italia | Italy | 1945- | 600 |
If there are any missing inscription, tell me : marcosampaio@grupo.bfe.pt
