Frequently Asked Questions

What is a joint stamp issue ?

Joint stamp issues are stamps issued by at least two countries on the basis of a common event, usually at the same date (if technically possible) and sometimes with the same design. Postal administration cooperation is required. Actually the official definition of Joint Stamp Issues reads as follow:

A Joint Stamp Issue can be declared when two or more independent postal administrations reach an agreement to create new postage stamps or items for postal use with a common interest, and issue them within a predefined and commonly agreed time frame.

What is a ‘true’ joint stamp issue ?

This is probably the most difficult question to answer, but should be in accordance with the official definition provided above. Of course, some of the stamp issues which are reported in the catalogue are at the limit of this definition for joint stamp issues. Definitely omnibus series and colonial stamp issues are not joint stamp issues if they are originating from the same printing house with a central decision process. But stamps using the same design issued at the same date are not necessarily joint stamp issues, unless this specification is well documented by the postal administrations from all involved countries, or unless a mixed document (all stamps with FDC’s cancellation on the same cover) can be provided as proof. We must admit that these proofs have not yet been found for all reported stamp issues in particular for very old stamp issues (before the 1960s) when the concept of joint stamp issue was not really established.

What is a twin stamp issue ?

Twin” stamp issues [T] are a special case of joint stamp issues were designs are identical and the release date is the same for all involved countries .

What is a se-tenant joint stamp issue ?

A “Se-tenant” joint stamp issue (formerly called siamese stamp issue) [S] is a special case of twin stamp issue in which the stamps from both countries are physically linked together i.e. se-tenant or within the same miniature or souvenir sheet. The case in which only one stamp is issued with this stamp bearing the name of both countries, is called “Unique” stamp issue [U].

Can stamps released at the same date by two different countries but with a different design be considered as joint stamp issues ?

Of course, yes. However, same date of issue is not sufficient. Some stamps are released to celebrate for exemple an anniversary (stamp issued on any birthday), which does not mean that all involved postal administrations have decided to produce them jointly. This can even happen with stamps with the same design, for which, for example, the picture may be taken from the same source (same painted portrait used at the occasion of the anniversary of this individual) without concertation between postal administrations.

How many days can separate the dates of release for an issue still to be considered as a twin stamp issue ?

Usually twin stamp issues are released on the same day. It may however differ in some cases. The policy of France for example is to release the new stamps always on a Monday, but collectors are able to buy these stamps the Saturday before and only at special places (pre-sale) with a first day cancellation dated from the Saturday. So, at least two dates can be considered as first day cancellation in France (pre-sale date and counter sale date).

It happens also that with joint stamp issues the partner country does not want to change its usual release day. So mixed cards can be obtained only on this official working day and, as a consequence, the two dates on these mixed cards can differ by a few days. 
For technical reasons it happen also that some stamps in one country are released with delay. Actually, with a difference in dates of more than one week (7 days), the stamp issue cannot be considered anymore as a twin stamp issue. This led to the creation of the sub-type “Concerted” stamp issue [C].

Is there a way to differentiate joint stamp issues released at the same date but with different designs from stamps released at different dates but with the same design ?

To answer to this question, it was proposed to give the name “Concerted joint stamp issues [C] to stamps with the same design issued at different dates (which may happen also accidentally) and the name “Parallel joint stamp issues [P] to stamps issued at the same date but with different designs. However, we have to take care about “accidental” same design, i.e. same design used because taken from a common original reference (i.e. only one portrait of Christopher Colombus is existing, so all stamps honoring this man have almost the same design and obviously are not joint stamp issues).  

Can I limit my collection to twin stamp issues ?

Of course, yes. Everybody is free to collect what he wants. There are today enough twin stamp issues that were released worldwide and they can even lead to nice collections limited to sub-topics. Most of the collectors specialized in joint stamp issues collect stamps with the same design, but almost all do not keep colonial or omnibus series, which are beyond the official definition, despite close similarities. Other collectors limit their collection to topics or countries (e.g. only European countries).

What are omnibus series ?

The countries belonging to the Commonwealth used to release at the same date identical stamps for which only the name of the country and sometimes the postal values were different. Same happened with the French or Portuguese stamps produced for their colonies. These stamps produced between the year 30’s to 50’s were called ‘omnibus series‘. This denomination applied later to stamps released by other countries such as former colonial dependencies for which it was less expensive to base their stamp program on a common design (French, Dutch or Portuguese former colonies for example). All these are not true joint stamp issue but Territorial/Colonial stamp issues, still reported in the catalogue but under the categories “Dependencies” [D] or “Omnibus” [O] when the number of involved countries goes beyond five. In fact the word Omnibus was coined before the creation of true joint stamp issues and is almost exclusively used for the Commonwealth territory stamps. More recent countries issuing identical stamps without concertation between them, but simply produced at the same printing house (usually independent African countries), are definitely not joint stamp issues and even, if considered by some as Omnibus, are reported as Non-accepted series.

Why are large series with identical stamps not considered as joint?

Today, some small countries using the same stamp printing house (House of Questa, Crown Agents, Stamperija,…) can be proposed to enter in a large series (stamps with the same frame design) involving dozen of countries which are not necessarily politically linked (some times also called erroneously omnibus series). These stamps cannot be considered as omnibus series (this was the case in the previous editions of the catalogue), but as common design or “Borrowed” stamp design [B] and are “Non-approved” joint stamp issues [N]. Note also that on top of this, these stamps are produced in so many large numbers that they have to be considered as abusive stamps which are not recommended to be collected, despite their official status. These stamps are reported in the catalogue, but only in a summarized form.

On the contrary, Europa CEPT stamps with the same design and the same date of issue for the major part of the countries are considered as true twin stamp issues, because based on a common decision and produced locally. This happened only between 1956 and 1973, in 1984 and more recently in 2000 and 2016.

What are mixed covers ?

A mixed cover is a document bearing all joint stamps issued by all involved countries with stamps respectively first day cancelled. It can also be a postal card or a leaflet issued by the postal administration or any other document as long as stamps and cancellations are present. This document is actually the proof of a true joint stamp issue. A joint stamp issue collection can be limited to mixed covers. The term dual cover is also used when only two countries are involved, but means the same.

How about maxi-cards with joint stamp issues ?

Mixed joint stamp issue maxi-cards refer to documents for which all stamps and cancellations are affixed on a post card related to the topic instead of a cover. For purists, the post card has had to be created before the joint stamp issue. They are actually another form of mixed documents but quite rare, mainly for technical reason, i.e., due to the fact that on a postal card there is only little space left for two stamps with cancellations. This is also a very nice collection to start now !

How many countries are usually involved in a joint stamp issue ?

At minima two of course, sometimes three countries are involved in a true joint stamp issue. Independently of the number of countries, they are considered as a true joint stamp issue, as long as all participating countries issue their stamps according to a centralized decision. Also, in particular when the number of countries is higher than five, one has to check carefully if there is not a political link between all those countries (colonies for example, then it has to be reported as “Dependency” stamp issue [D]) or if this series was not produced at one single place (omnibus series, common stamp issue, therefore a “Non-accepted” stamp issue [N]), before defining this set of stamps as joint stamp issues.

How about territorial stamp issues?

Colonial or territorial stamp issues with the same design issued at the same date could be considered as sub groups of twin stamp issues and could be named colonial or territorial twin stamp issues. However, as usually only one country decides for issuing both stamps, they cannot be considered as true joint stamp issues. These stamp issues are reported in the catalogue, with the mention ‘Territorial’ or ‘Colonial’ and reported in the sub-class “Dependency” stamp issues [D]. This class includes of course the former colonial issues from France, Portugal or Spain, but recent countries involved in such stamp issues include for example Denmark with Groenland, Portugal with the Açores and Madeira, the Netherlands with Aruba, Suriname and the Dutch Antilles.

What is the difference between a Twin stamp issue and a Borrowed design stamp issue?

Some stamps can be based on almost exactly the same design, but have been created without any discussion between postal administrations. In fact this design can be provided by a third party to promote either an event or an anniversary or be used to collect funds (e.g. breast cancer fund raising campaign). Date of issues can differ by up to tens of years. As there is no relationship between the different postal administrations, these stamp issues cannot be considered as “Twin” or “Concerted“, but will simply be filed as “Borrowed” design stamps [B], a sub-class of “Non-accepted” joint stamp issues [N]. They are reported in the catalogue, without extensive details, just to avoid too frequent questioning about relevance.

Can the United Nations Organization stamps from the three offices New York, Geneva and Vienna be considered as joint stamp issues ?

Definitely not, even if the design is the same. These stamps are defined by a single entity (postal administration) which can alone decide to issue identical stamps or not. These stamps are just listed for information. However, when another country is also involved on top of UN stamps, of course they have to be included as a true joint stamp issue.

Why having not included all the Europa stamp issues ?

From 1974 on, all stamps issued by the European countries were produced at different dates and only the topic was defined. In 1984, one identical design (the European bridge) was accepted, but issue dates remained spread over 10 months. The situation was similar in 2000 and 2016, when identical design stamps were produced as Europa-CEPT (PostEurop) stamps for these years. So, Europa is not anymore a joint stamp issue, with the exception of years during which the different countries agree on a common design. As a few countries issue their stamp at the same date (usually around May 9 of the year), such a series can even be considered as a twin stamp issue.

When was the first joint stamp issued ?

This question is difficult to answer because it depends on how are defined joint stamp issues (see definitions above). However, one can consider the following dates as references:

  • In terms of first mention in the catalogue, how about the New Brunswick – Nova Scotia stamps from September 1, 1851 ? or the 1860 British Columbia and Vancouver Island stamps ? But those are Territorial joint stamp issues
  • How about June 1, 1867, with the Austro Hungarian precursors. One single stamp was used in two countries, Austria and Hungary, which formed initially one empire. Even after separation of the two countries, these stamps continued to be used for years. This was possible because the stamp did not bear the name of any country and the abbreviation of the currency was the same for both countries.
  • The 1938 Entente stamps between Greece, Yugoslavia, Turkey and Romania has probably to be considered as the first joint stamp issue although not all of the stamps were produced at the same date
  • During the same year, France issued the Pierre and Marie Curie stamps involving all their colonies (France on September 1, 1938, while colonial country stamps were issued on October 24, 1938). One month later, Cuba issued also the same stamps in Spanish (November 23) and Afghanistan issued another stamp on December 23. Unfortunately, it is better to consider this stamp issue as a territorial stamp issue with associated countries using a borrowed design
  • The first true twin stamp issue was planned to be produced between Great Britain and France. It represented King George VI and the French President Albert Lebrun. This stamp issue initially planned for year 1939, delayed to 1940, was finally aborted as a consequence of the war.
  • A joint stamp issue was released by Colombia (September 3, 1946) and Venezuela (August 24, 1946) in honor of the poet Andres Bello and should be considered as the first concerted stamp issue, as the dates of issue differ by almost two weeks. It would be interesting to find a dual cover with these stamps.
  • On September 15, 1956, the first Europa series involving 6 countries can be considered as the first non-colonial twin stamp issue (same date, same design). This series was followed one month later (October 30, 1956) by the equivalent Norden stamp issue involving five countries.
  • August 27, 1958, can be considered as the birth date of the first true twin stamp issue involving two countries: Australia and New Zealand to celebrate the 30th anniversary of the flight over the Tasman sea by Sir Charles Kingsford Smith.
  • The first se-tenant joint stamps were issued by Yugoslavia and Romania on April 30, 1965
  • Only on May 24, 1986, a first twin stamp issue based on postal stationeries, not stamps was issued: USA – Italy, Francesco Vigo.
  • An aerogramme was first involved in a twin stamp issue together with the stamps released by Switzerland (joint issue with China) on November 25, 1998.