When Should You Get Your ISBN, and What If You Waste One?

Get your ISBN before you finish the print cover and the copyright page, because both carry it. You do not need to have published the book yet. And if you end up with an ISBN you did not use, don’t plan to reuse it on another book: the ISBN rules say an assigned number is never reused. Below is what to do at each stage.

When should I get my ISBN?

Before your cover and copyright page are final. IngramSpark’s ISBN facts article says you must have your ISBN “purchased, assigned, and ready to go before you design your book cover”. It also says you can buy ISBNs before the book is finished and the book does not need to be published first.

The ISBN sits in three places: the barcode on the back cover, the copyright page inside the book, and the details you type into KDP or IngramSpark. Changing it later means redoing all three. My post on how to write a copyright page shows where it goes.

What do I do once I have the ISBN?

Match every detail to it. KDP’s ISBN help page says that if you use your own ISBN, you must enter the same book title, author name and publisher you registered it with. Then put it on the copyright page, make the barcode for the cover, and enter it for that format only.

One ISBN covers one format. IngramSpark says each format needs its own unique ISBN, and the ISBN International site says each product form, such as paperback or EPUB, is identified separately. Your paperback, hardcover and ebook are separate numbers. KDP does not require one for the ebook.

Can I change the ISBN if I got it wrong?

Yes, while the book is a draft. KDP’s help page says you can update the ISBN if the book is still in draft, and that “ISBNs cannot be changed if your book is published.” After that you unpublish and publish a new edition. I explain what that does in switching from KDP’s free ISBN.

Can I reuse an ISBN I did not use?

Not on a different book. The ISBN International users’ manual (sixth edition, 2012) says an ISBN, once assigned to a publication, can never be reused to identify another publication, even if it was assigned in error. IngramSpark says the same: ISBNs cannot be reused once assigned.

Those pages do not say what happens to a number you assigned to a title that never went on sale or that you deleted. I could not open Bowker’s help pages, so I can’t tell you its rule. Ask your ISBN agency before you count on getting that number back, and keep one note of which book each number belongs to so you never assign two.

Can I backdate an ISBN?

I found no rule that lets you, and I would not try. A number is not dated when you get it. The book’s publication date is a separate detail you enter when you list it. Put the real date you plan to publish and update it if the launch moves.

What I do about it

If you want the ISBN sorted before you design the cover, I can publish your book under my imprint, Urgesta AS. I deliver the ISBN and barcode within 2 business days of getting complete book details, so you have the number when you build the cover and copyright page. You keep all rights and royalties, and there is a 7-day money-back guarantee. The ISBN then stays with Urgesta AS. See how it works.

Still deciding? Read how much an ISBN costs and where to get an ISBN number.