Stamp Collecting for Beginners and Philatelists
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Easy Stamp Finder
Identifying Stamps: O
To identify your stamp, examine your stamp for an inscription. Then match the printed inscription on the stamp to a term in the inscription lists.
If you can't find your stamp's inscription in the list, choose another, and if you need more help in identifying your stamp, you can post your question on our stamp discussion forum.
| Stamp inscription | Country of issue |
| O. A. (overprint) | South Australia » official |
| O.$. (overprint With Airplane) | Bulgaria » airmail |
| O.B. (overprint) | Philippines » official |
| O.F. Castelloriso (overprint / France) | France » Castellorizo occupation |
| O.H.E.M.S. (overprint) | Egypt » official |
| O.H.H.S. (overprint) | Egypt » official |
| O.H.M.S. (overprint) | Canada » official |
| O.K.C.A. Pocci | Russia » Army Of The North |
| O.L. (overprint) | Monaco |
| O.M.F. Cilicie (overprint / France) | France » occupation Of Cilicia |
| O.M.F. Syrie (overprint / France) | Syria |
| O.N.F. Castellorizo (overprint / French Levant) | France » Castellorizo occupation |
| O.P.S.O. (overprint) | New Zealand » official |
| O.S. | English speaking countries » official |
| O.S. | Norway » official |
| O.S.G.S. (overprint) | Sudan » official |
| O.T. (overprint) | Czechoslovakia » newspaper stamp |
| O.U.S. (overprint /wavy lines) | Great Britain |
| O.W. Official (overprint) | Great Britain » official |
| OKCA | Russia » Army of the North |
| Oaha Mapka | Finland |
| Oaxaca | Mexico » Oaxaca |
| Obock (overprint / French colonies) | Obock |
| Obock | Obock |
| Occupation Azirbayedjan (overprint / Russia) | Azerbaijan |
| Occupation Francaise (overprint) | Hungary » French occupation |
| Occupation Francaise Cameroun (overprint / Middle Congo) | Cameroon » French occupation |
| Oceanie | French Polynesia |
| Ocupacion De Pasqua | Chile » semipostal |
| Oesterr Post Liechtenstein | Liechtenstein » Austrian Postal Administration |
| Oesterr Post With Kais Koenigl | Austria |
| Oesterr. Post | Austria |
| Oesterr | Austria |
| Oeuvres De Guerre (overprint) | Cameroon » semipostal |
| Oeuvres De Solidarite Francaise | French Colonies » semipostal |
| Oeuvres Sociales | St. Pierre & Miquelon » semipostal |
| Off.Sak. | Norway » official |
| Offentlig Sak | Norway » official |
| Official | Tanganyika » official |
| Officiel (overprint) | Iran |
| Officiel (overprint) | Luxembourg » official |
| Offisieel-Official | South Africa » official |
| Offisieel | South West Africa » official |
| Ohu Post | Estonia » airmail |
| Oil Rivers | Niger Coast Protectorate |
| Okca | Russia » Army Of The North |
| Oldenburg | German States » Oldenburg |
| Oltre Giuba | Oltre Giuba |
| Olym | Greece |
| Oman, State of | Oman |
| Oman, Sultanate of | Oman |
| On C.G.S. (overprint / India) | India » Cochin » official |
| On K.D.S. (overprint) | India » Kishangarah » official |
| On L.F.S. (overprint) | India |
| On S.S. (overprint) | India » Travanacore » official |
| On S.S.S. (overprint) | India » Sirmoor » official |
| On State Service (overprint) | Iraq » official |
| Onza | Spain » official |
| Orange River Colony (overprint / Cape Of Good Hope) | Orange River Colony |
| Orange River Colony | Orange River Colony |
| Oranje Vrij Staat | Orange River Colony |
| Oranje Vrij Staat | Orange River Colony |
| Orcha | India » Orchha |
| Orchha | India » Orchha |
| Ordinary (overprint) | Liberia |
| Ore (value) | Denmark , Sweden, Norway |
| Organisation Mondiale De La Sante (overprint) | Switzerland » World Health Organization » official |
| Oro Pastas | Lithuania » airmail |
| Orphelins De La Guerre | France » semipostal |
| Orts Post | Switzerland |
| Orts-Post | Switzerland |
| Osten (overprint / Germany) | Poland » German occupation |
| Osterr-Post | Austria |
| Osterreich, Republik | Austria |
| Osterreich | Austria |
| Osterreich | Austria |
| Osterreichische Post | Austria |
| Osterreichische Post | Austria |
| Ostland (overprint / Germany) | Russia » German occupation |
| Ottomanes Postes | Turkey |
| Otvorenie Slovenskeno (overprint / Czechoslovakia) | Slovakia |
| Oubangui-Chari-Tchad (overprint / Middle Congo) | Ubangi |
| Oubangui-Chari | Ubangi-Shari |
