If you plan to publish:
*more than one book,
*on more than one platform (POD or offset-printing) and/or,
*in more than one format,
then you should
1. purchase your own ISBN, and
2. buy in bulk.
ISBN stands for International Standard Book Number. Think of it like your book’s social security number. You will need one ISBN for each edition and format of your book. “The ISBN identifies the publisher as well as the specific book title, edition and format (hardback, paperback, ePub, PDF, Mobi, Audio…).”*
Print-on-demand (POD) services like KDP and Ingramsparks offer free ISBNs, which can be tempting to use given the already enormous cost of self-publishing. However, beware! As stated on the Ingramspark’s website, “By using their free ISBN, your publisher imprint will not be associated with your book- it will hold IngramSpark’s imprint. This may limit where you can print and distribute your own [book].” (See: Ingramsparks.com/free-isbns)
Similarly, KDP states on their website, “The free ISBN from KDP can only be used on KDP for distribution to Amazon and its distributors.”
So, a KDP ISBN can only be used to publish your book through Amazon, nowhere else.
You can purchase just one ISBN or in bulk.
1 ISBN= $125
10 ISBNs= $295
100 ISBNs= $575
As a self-publisher, using your own ISBN gives you more freedom to print and distribute your book wherever and through whomever you’d like, and buying in bulk could save you money down the line. It’s a win, win.