About ISSNs

The International Standard Serial Number (ISSN) is an internationally recognized 8-digit code that uniquely identifies a serial or other continuing resource based on title and medium. Canadian publishers are not obligated to obtain ISSNs, but Government of Canada publishers are required to use them. An ISSN is displayed on a publication and becomes a permanent attribute.

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Where to get an ISSN

ISSNs are assigned by national centres (such as ISSN Canada) in accordance with the international standard, ISO 3297, Information and documentation — International Standard Serial Number, and the ISSN Manual.

Obtain an ISSN.

ISSNs and titles

An ISSN uniquely identifies a serial or other continuing resource based on title and medium. The title must be clear and stable from issue to issue, or from part to part. Use the same ISSN on every issue of a serial or other continuing resource as long as the title remains unchanged.

Construction of ISSNs

The parts of the code have no inherent meaning. The number starts with "ISSN" to avoid confusion with other numbering systems, followed by a space.

The number consists of 8 digits, appearing as 2 groups of 4 digits separated by a hyphen. The digits are Arabic numerals 0 to 9, but the last or check digit may be an upper case letter "X" representing the number 10. The check digit guards against data transcription errors.


  • ISSN 0027-9633
  • ISSN 1927-226X

Advantages of ISSNs

Canadian publishers do not need to obtain ISSNs, but there are many advantages to using them:

  • uniquely identify a serial or other continuing resource in any language or from any country in accordance with an international standard
  • provide an easy way to communicate data among publishers, suppliers, subscription agencies, database providers, researchers, and libraries
  • provide a point of access to publishers' catalogues, trade directories, inventories, bibliographies
  • are used in libraries to identify, order, and process titles, as well as to check in and claim missing issues
  • simplify interlibrary loans and union catalogue listings
  • are used in databases for updating and linking files, and for retrieving and transmitting data
  • are an essential element of these barcodes: International Article Number (EAN) and Serials Industry Systems Advisory Committee (SISAC)

When to get a new ISSN for a title

You must request a new ISSN when:

  • the title changes
  • you publish the title in a new medium

Do not print or display an old ISSN on a new title. When a title is no longer published, do not reuse the ISSN assigned to that title. You do not need a new ISSN for changes in numbering, date, frequency, publisher, or place of publication.

Contact ISSN Canada about any planned title change.

Publications that may also have an ISBN

Some types of publications, such as annuals or biennials, may be assigned both an ISSN and an International Standard Book Number (ISBN). Books published in a monographic series may have both an ISBN for the individual book and an ISSN for the entire series.

ISSNs and copyright

An ISSN does not grant copyright protection or exclusive rights to a title. Contact the Canadian Intellectual Property Office for information about copyright.

Government of Canada publications

Departmental publishers must obtain an ISSN as required in the Procedures for Publishing.


These definitions are based on ISO 3297, Information and documentation — International Standard Serial Number.

Continuing resources
Publications in any medium that are published over time without a planned end and are available to the public. Serial publications and ongoing integrating resources are types of continuing resources.
Serial publications

Publications in any medium that are issued in successive parts and intended to be continued indefinitely. Each issue of a serial usually has a number and/or a date (such as volume and issue number, and/or month and year) that distinguishes the individual issues of the serial from each other.

Serials include periodicals, magazines, journals, newsletters, newspapers, annuals (reports, yearbooks, directories, etc.), conference proceedings, and monographic series.

Monographic series

A group of separate publications (each having a distinctive title and also having a collective title for the whole group). To be eligible for an ISSN, both the monographic series title (the collective title) and the distinctive title of the individual publication must appear together.


  • title of a monographic series: "Crime and Justice Research Paper Series"
  • title of an individual book in the monographic series: "Exploring Crime Patterns in Canada"

A monographic series excludes multi-volume sets consisting of a finite number of parts, even if all parts are not issued simultaneously.

Ongoing integrating resource
A publication in any medium that is updated at any time by adding information or by replacing obsolete information with new information. The updates are integrated into the whole resource and are made available to the public. Examples include loose-leaf publications, websites, blogs, institutional repositories, directories and databases.