International Standard Identifier for Libraries and Related Organizations (ISO 15511)

The purpose of ISIL is to define and promote the use of a set of standard identifiers for the unique identification of libraries and related organizations with a minimum impact on already existing systems.

ISIL identifiers are assigned on request by the ISIL allocation agencies listed below. Libraries and other organisations may request ISILs also to their subordinate units such as branch libraries if and when necessary.

Both ISIL and ISNI (International Standard Name Identifier - ISO 27729) can be used to identify libraries, but they have different functions. ISNI is used in cataloguing for unique identification, whereas ISIL is used in circulation and interlibrary lending. 


Contact ISIL Registration Authority

AR Argentine Republic Argentine Standardization and Certification Institute (IRAM) n/a
AT Austria Die Österreichische Bibliothekenverbund und Service GmbH Search
AU Australia National Library of Australia Search
BE Belgium Royal Library of Belgium Search
BY Belarus National Library of Belarus n/a
BG Bulgaria National Library of Bulgaria Search
CA Canada Library and Archives Canada Search
CH Switzerland Swiss National Library Search
CY Cyprus Cyprus University of Technology – Library List
DE Germany Staatsbibliothek zu Berlin Search
DK Denmark Danish Agency for Culture and Palaces List
EG Egypt Egyptian National Scientific and Technical Information Network (ENSTINET) Search
FI Finland The National Library of Finland Search
FR France Agence Bibliographique de l'Enseignement Superieur Search
GB United Kingdom British Library List
GL Greenland Central and Public Library of Greenland List
HU Hungary National Széchényi Library List
IL Israel National Library of Israel List
IR Islamic Republic of Iran National Library and Archives of Islamic Republic of Iran of Iran Search List
IT Italy Istituto Centrale per il Catalogo Unico delle biblioteche italiane e per le informazioni bibliografiche Search
JP Japan National Diet Library List
KR Republic of Korea The National Library of Korea Search
LU Luxembourg Archives nationales de Luxembourg List
NL The Netherlands Koninklijke Bibliotheek, National Library of the Netherlands n/a
NO Norway National Library of Norway Search
NZ New Zealand National Library of New Zealand Te Puna Matauranga o Aotearoa Search
QA Qatar Qatar National Library (QNL) Search
RU Russian Federation Russian National Public Library for Science and Technology n/a
SI The Republic of Slovenia National and University Library List
SK Slovak Republic Slovak National Library List
US United States of America Library of Congress Search Search

Non-national ISIL Allocation Agencies and code prefix for the identifiers

EUR Code for common European organizations. HAEU List
O Code O (letter) for OCLC for technical encoding in e.g. RFID tags. See OCLC -
OCLC WorldCat Symbol OCLC Search
ZDB Staatsbibliothek zu Berlin - Zeitschriftendatenbank Staatsbibliothek zu Berlin Search


An ISIL country code is the equivalent of the codes specified in ISO 3166-1.

See ISO 3166-1 decoding table:

ISIL is developed within the framework of Technical Committee 46/Subcommittee 4 (TC46/SC4)

TC 46 - Information and Documentation - SC 4 - Technical Interoperability
SC4 at ISO homepage

International Organization for Standardization

If you want to buy the standard, please contact national member body of ISO: or go to ISO 15511 in ISO Catalogue 


If you have enquiries or questions regarding libraries and litterature, please contact us here.

Dialogboksen begynder her. Du kan lukke boksen ved at trykke Accepter cookies knappen eller Enter. Knappen er det sidste element i boksen.

Vi benytter cookies til at forbedre brugeroplevelsen.

På anvender vi cookies. Cookies er i mange tilfælde nødvendige for at få en hjemmeside til at fungere. Vi bruger cookies for at forbedre din oplevelse, samle statistik og huske dine indstillinger. Ved at klikke på "Accepter cookies" godkender du dette.

(dialogboks slutter)