Self Publishing
Why ISBN is Important for Self-publishing
The ISBN number thing, in plain English
If you’re wondering ISBN what it is, here’s the simple version: ISBN stands for international standard book number. It’s a number assigned to books so the world can tell them apart. Think of it as a label that helps systems recognize your book correctly. It’s not copyright protection. It’s not a barcode (though a barcode can be made from an ISBN). And it’s definitely not a secret handshake that proves you’re a “real” author.
While the majority of readers typically look for books by title or author ISBNs matter because they’re the number used by shops, distributors and libraries to search a book. That’s the heart of how ISBNs are used, they help databases find the exact title and edition you mean.
- Retailers use ISBNs to list, order, and stock the right book.
- Libraries use ISBNs to catalog and track books in their systems.
- Distributors and databases use ISBNs to match metadata (title, author, format, price) to the correct record.
How many ISBN numbers do I need?
Here’s the key detail many self-publishing authors miss: an ISBN doesn’t just identify your “book.” It identifies a specific format and edition. Hardcover, paperback, ebook, large print, each one is treated as its own product in the supply chain, and you will need and IBSN for each format you publish.
Think of ISBNs like luggage tags, no one admires them, but they stop your suitcase from going to Timbuktu. The ISBN tells the system, “Nope, not the eBook, send the paperback.”
How ISBNs work across formats (paperback vs hardcover)
Think of an ISBN like a product ID. A paperback is a different product than a hardcover, even if the content is the same. That’s why how ISBNs work across formats matters so much when you’re planning your launch.
Here’s the rule you can rely on: each format/edition needs its own ISBN, and ISBNs cannot be reused once they’re assigned. So if you change formats (or create a new edition), you will need a new one.
If you’re publishing in print, you’ll almost always need ISBNs for each print format:
- Paperback = 1 ISBN
- Hardcover = 1 different ISBN
This is why people talk about ISBN for multiple formats, because your “one book” can quickly become two (or more) ISBNs once you add editions.
ISBNs for Paperback and eBook
Now for the part that surprises most authors: you don’t actually need an ISBN for your ebook. You can get one, but it’s optional. So when you’re deciding on ISBNs for paperback and ebook, remember that the ebook is the flexible one.
If you’re buying ISBNs (instead of using a free option), skipping the ebook ISBN can be a simple way to save money, especially if your retailer doesn’t require it.
One more note: first-time authors often grab free ISBNs to cut costs, but experts point out this is usually more convenient for the platform than a long-term win for your publishing independence. Owning your ISBNs can also help you track sales performance by edition more cleanly.
Free ISBN through IngramSpark or KDP – what you’re really getting
A free ISBN is an ISBN assigned to your book by a print-on-demand (POD) company. The most common example is the free ISBN offered by KDP. During paperback setup, KDP lets you choose a free ISBN instead of buying your own.
The trade-off isn’t about ownership, it’s about how your book is labeled in industry databases. When you use a platform-issued ISBN, the POD company becomes the publisher of record. That means the service imprint listed as publisher shows up on your book’s listing page and in metadata feeds that bookstores and libraries use. This does not mean that the print on demand company owns the rights to your book. You still own the rights.
You’re still the author, and you still control your content. But your “independent publishing credentials” may look different if a retailer, librarian, or event organizer searches your title and sees a platform name instead of your imprint.
Another important consideration is flexibility. Free ISBNs can tether your print book to the issuing service’s ecosystem. For instance, obtaining a free ISBN through Amazon limits your distribution options since it is assigned under Amazon’s KDP imprint.
This can complicate the process of presenting your book as publisher-controlled across various print vendors. If you decide to print the same book title through a different service, you might need to acquire a new ISBN, which can result in fragmented reviews, listings, or bookstore ordering records.
For many first-time authors free ISBN is a smart, simple choice, especially if you’re publishing one book, testing an idea, or treating publishing like a hobby. If you’re building a business, planning multiple releases, or want your own imprint name everywhere, a paid ISBN gives you control over who is listed as the publisher.
Picture this: you’re at a local bookstore event, someone pulls out their phone, and looks up your book. Do you want the publisher line to show your name/your imprint, or the POD platform? That one moment often clarifies whether “free” is truly the best fit for your goals.
Benefits of getting your own ISBN
The number one benefit of getting your own ISBN is simple: you decide who shows up as the publisher. When you use a free ISBN from a platform, that platform is often listed as the publisher in the book’s metadata. When you buy your own, you can list:
- Your personal name (clean and straightforward)
- Your imprint name (more “publisher” vibes)
This is the heart of publisher of record status, your book is officially tied to you (or your imprint), which supports your brand and your independence. It’s a big reason why indie authors should own ISBNs when they’re building a long-term career.
Create your own publishing imprint (and look instantly more pro)
Having your own set of ISBNs simplifies the establishment of your publishing imprint, ensuring consistency throughout your catalog. For instance, an author may choose to publish under the name Stone Ridge Books, having formed business with that title, developed a dedicated website, and even launched non-fiction works under the same brand.
This consistency not only enhances the author’s branding but also cultivates a more professional presence on retailer platforms and within industry databases. If you intend to publish multiple titles, owning your ISBNs enables you to maintain a single publisher identity across your entire collection. The visual effect of the same imprint on every book may seem subtle, yet it conveys a serious commitment to your craft and helps streamline your back-end metadata.
For those treating publishing as a hobby with plans to release only one book, free ISBNs might suffice. However, if your aim is to build a publishing business, investing in your own ISBNs represents a significant professional advantage.
Here’s the messy part. If you start with free ISBNs and later decide you want one imprint across all your books, you may end up republishing older titles with new ISBNs you own. That can effectively create a new edition and can be tricky to connect on retail sites. I republished my first books with a new ISBN that I owned, and it basically meant that I published a second edition of all those older books that I had.
Why is my book listed twice?
For a long time, one big question in ISBN for self-publishing authors was: “Do you want to publish with IngramSpark, amazon KDP, Lulu, Books.by?” It used to matter because IngramSpark only accepted ISBNs you bought and owned. That’s changed. You can now use a free ISBN through IngramSpark, so IngramSpark alone isn’t the deciding factor anymore.
The real catch with free ISBNs is that they’re often “locked” to the platform that issued them. In plain terms: a free ISBN from one print-on-demand (POD) company usually can’t be reused somewhere else.
- IngramSpark will accept its own free ISBNs.
- KDP won’t let you use an IngramSpark free ISBN.
- Barnes & Noble Press also won’t take that same free ISBN.
When you self‑publish the same book through several platforms such as KDP and IngramSpark and accept a free ISBN from each, you are effectively giving that one book multiple identities. Each platform‑issued ISBN is treated by the book trade as a completely separate edition, even if the content, title, and cover are identical. Because book databases, retailers, and libraries rely on ISBNs to identify and catalogue books, the same title can appear more than once in listings, search results, and catalogues, with each entry tied to a different ISBN.
This can confuse retailers and readers, split sales data and reviews across multiple records, and make the book look like duplicates rather than a single, consistent product. Using your own single ISBN for the same format across all platforms avoids this problem by ensuring that everyone in the supply chain recognises the book as one edition, no matter where it is distributed.
How to Fix the Issue
The first option is to buy one ISBN and use it everywhere. This keeps your metadata consistent across all platforms and makes future changes much easier. When the same ISBN is used on both KDP and IngramSpark, the systems can match the records, so your book appears only once on Amazon instead of as duplicate listings. In this setup, Amazon orders are usually fulfilled by KDP, while IngramSpark handles orders from the wider distribution network.
The second option is to use only one platform. If you want to avoid paying for an ISBN, you can publish solely through IngramSpark and still have your book available on Amazon as well as through their expanded distribution channels. The downside is that you will usually earn less per Amazon sale than you would if you published directly through KDP.
One additional thing to keep in mind is that IngramSpark offers good print quality and wide reach, but it is not very beginner‑friendly. It is worth doing thorough research before uploading your files or setting discounts, ideally following step‑by‑step guidance rather than trial and error.
