guide to isbn numbers and self-publishing

Benjamin Burrows

Managing Director

guide to isbn numbers and self-publishing

When it comes to book printing, ISBN numbers play a critical role in connecting authors, publishers, and readers. But what exactly is an ISBN number, and why is it important when self-publishing?


When I talk to customers enquiring about book printing, the topic of ISBN numbers usually comes up.

There’s often some confusion around when an ISBN is required and how to go about securing one. This article aims to answer some of the common questions and to provide a useful reference point if you’re thinking of self-publishing.

what is an isbn number?

An International Standard Book Number (ISBN) is a unique identifier assigned to each edition and variation of a publication – so the paperback and hardback will each have a unique ISBN. A book’s ISBN number is universally and internationally recognised and, as well as facilitating easy identification and distribution, helps authors and publishers to protect their intellectual property and track sales and inventory data. It also enables libraries, retailers, and consumers to locate and purchase books efficiently.

A fan of Oxford Preservation Trust books showing back covers with ISBN numbers and barcodes

Even in today’s digital world, ISBN numbers remain a crucial ingredient in book publishing: they are required for ebooks as well as printed books. With the ever-increasing number of self-publishing authors and digital platforms, understanding and utilizing ISBN numbers is essential for publishing success.

does my book need an isbn?

An ISBN number is only required if you plan to sell your book. We work with plenty of self-publishing authors who create memoirs or picture books to share only with friends and family. In these cases, an ISBN is not necessary. However, for any commercial book printing project, an ISBN will be required.

how are isbn numbers issued?

In the UK and Ireland, ISBN numbers are managed by Nielsen BookData, part of NielsenIQ. As well as issuing the unique codes, Nielsen maintains a database of metadata for every title with an ISBN number.

When an ISBN is assigned and registered with Nielsen, certain mandatory information must be provided. This includes the book’s title, author’s details, publisher, publication date, and price. The registration process also provides options to record information about the physical characteristics of the book, such as the number of pages, size, and format.

Nielsen’s database allows bookshops and anyone else to access information about every book. It also notifies the British Library of a book’s existence.

isbn numbers and legal deposit

The British Library is the nation’s primary legal deposit library – one of six named in UK law. The UK’s system of legal deposit became law in 1662 and now requires a copy of every UK publication to be sent to the British Library.

New publications can also be requested by any of the other five legal deposit libraries (the National Library of Scotland, the National Library of Wales, Oxford University’s Bodleian Library, Cambridge University Library, and Trinity College Dublin Library). Should the Agency for the Legal Deposit Libraries make a request on behalf of any of these libraries, you will be obliged to send it five copies. For this reason, anyone publishing a book should be prepared to surrender up to six copies for legal deposit.

how to get an ISBN number for your book

Self-publishing authors can handle the purchase and registration of ISBN numbers directly with Nielsen BookData or seek the help of an experienced book publisher.

With well over 100 years of publishing experience, Holywell Press is geared to support you at every step of your book production journey. This includes handling the assignment and registration of ISBN numbers on your behalf.

If you need an ISBN number for your book, we can:

- assign a unique ISBN owned by Holywell Press to each version of your book
- help you apply for your own ISBN(s) as a publisher yourself
- register the ISBN(s) with Nielsen
- produce a barcode for the ISBN (an important and helpful addition if your book will be sold in bookshops)
- ensure all the relevant marks are correctly incorporated into your book’s artwork before printing.

Find out more about how to get a book printed and what makes Holywell a great partner for self-publishing a book. If you want to develop a better understanding of the design and printing process, check out some of our other quick guides, including: 

Of course, you don't have to be an expert to work with us. We’re always happy to explain your options, share our printing know-how, and show you in person what can be achieved. Call 01865 242098 or contact us using the button below.

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