This is the part of the guide where the order of operations may get a little…wacky. Some topics pair well together, but may Don’t worry, I’ll be sure to link back and forth to different sections and let you know when something important is coming down the road!
This may also be another good time to mention the Self Publishing Checklist to help you follow along! 😎
ISBNs are tied to the publisher (you), not the printer/distributor (Amazon, Ingram, B&N, or whoever). This means that, as long as your book is in the same format, size, and edition, you can use the same ISBN and Barcode across multiple print services. There is no law against it.
Where things can get hairy is if a printer/distributor requires you to have a unique ISBN or gives you a warning saying “ISBN already used.” Depending on how much time you have, and patience, you contact their support or find little workarounds on the internet.
In general, you need a unique ISBN if:
Here is a good article explaining more in depth what to look for: https://indiesunlimited.com/2017/09/24/do-i-need-different-isbns-for-createspace-and-ingram/
If you are choosing to publish anything through Ingram Spark, make sure you upload your titles here FIRST. For some reason, Ingram does not like when you try to add an ISBN that is already used on Amazon KDP. It will force you to enter a new one or transfer the title to them exclusively. (Silly, I know. YOU are the publisher, not them.)