ISBNs and Barcodes

What is an ISBN and do I need one?

An ISBN (International Standard Book Number) is a unique 13-digit identification number assigned to new publications. It should be displayed on the reverse of the title page and on the outside back cover. It is used by booksellers, publishers and libraries for ordering, listing and stock control. Although there is no legal requirement for an ISBN and it conveys no form of legal or copyright protection, it is essential if you want to sell your book through bookshops or online booksellers.

The Nielsen UK ISBN Agency allocates the numbers and there is a charge for this service. ISBNs can only be purchased in blocks of at least 10 numbers. A new number is needed for each new or revised edition and hardback and paperback books need different ISBNs as do each format of e-book. An ISBN should be applied for from the Nielsen UK ISBN Agency as soon as the book’s title is decided upon.

For more information contact:

Nielsen UK ISBN Agency
3rd Floor, Midas House, Goldsworth Road, Woking, Surrey, GU21 6LQ

Tel: +44 (0)1483 712 215
Fax: +44 (0)1483 712 214


The barcode of a book corresponds to its ISBN, and should be displayed on the outside back cover.  Like the ISBN the barcode is essential if you want booksellers to stock your book. Most printers will be able to generate a barcode from the ISBN.