ISBNs: what you need and what you don’t

Why do you need an ISBN? #

ISBNs are a key part of the publishing process, serving as a unique identifier for your book in the global marketplace. They are required by most major retailers, libraries, and distributors to track sales, manage inventory, and ensure accurate listings. Without an ISBN, your book may be ineligible for sale in many brick-and-mortar and online stores.

While some self-publishing platforms like Amazon KDP offer free ISBNs, these come with limitations. For instance, a free ISBN from Amazon KDP can only be used for distribution through Amazon, restricting your ability to sell through other channels. Additionally, the metadata associated with a free ISBN is often controlled by the platform, which can affect how your book is listed and discovered.

What does a free platform ISBN cost you? #

Opting for a free ISBN from a self-publishing platform like Amazon KDP or Smashwords may seem like a cost-effective choice, but it comes with hidden costs. Firstly, as mentioned, these ISBNs restrict your book’s distribution to the platform providing the ISBN. This means you cannot sell your book through other online retailers, bookstores, or libraries without obtaining additional ISBNs.

Secondly, the metadata associated with a free ISBN is controlled by the platform. This can limit your ability to manage how your book is listed and discovered, potentially affecting your book’s visibility and sales. For instance, if you want to update your book’s metadata or change your book’s categories, you may be at the mercy of the platform’s policies and procedures.

Finally, using a free ISBN can give the impression of amateurism to some industry professionals, such as literary agents and publishers. While this may not be a concern for all authors, it is something to consider if you plan to pursue traditional publishing opportunities in the future.

When should you buy your own ISBN? #

If you plan to sell your book through multiple channels, including major retailers, bookstores, and libraries, owning your own ISBN is highly recommended. This allows you to maintain control over your book’s metadata and distribution, ensuring that your book is listed accurately and consistently across all platforms.

Additionally, if you plan to publish your book in multiple formats (e.g., paperback, hardcover, e-book, audiobook), you will need a separate ISBN for each format. This is because ISBNs are format-specific, and using the same ISBN for different formats can cause confusion and errors in sales tracking and inventory management.

For authors who are unsure about their publishing plans, purchasing a block of ten ISBNs may be a cost-effective solution. This allows you to have multiple ISBNs on hand for different formats and editions, without incurring the full cost of buying them individually.

How much do ISBNs cost? #

In the US, the cost of an ISBN is set by Bowker, the official ISBN agency. As of 2026, the price for a single ISBN is $125, while a block of ten ISBNs costs $295. This means that if you plan to publish your book in multiple formats or through various channels, buying a block of ten ISBNs can be more economical, bringing the cost per ISBN down to approximately $29.50.

It’s important to note that ISBN prices can vary by country. In the UK, for example, ISBNs are provided free of charge by the Nielsen ISBN Store, but there may be limitations on the number of ISBNs you can obtain and the speed at which they are issued. Authors based outside the US should check the ISBN policies and prices in their respective countries.

What are the alternatives to buying an ISBN? #

If buying an ISBN is not feasible for you, there are a few alternatives to consider. As mentioned earlier, some self-publishing platforms offer free ISBNs, but these come with the limitations discussed above. Another option is to use a publishing service that includes an ISBN as part of their package. However, this can be more expensive than buying an ISBN directly from Bowker, and you may still face restrictions on how you can use the ISBN.

Finally, some authors choose to forgo an ISBN altogether and sell their books exclusively through their own websites or social media channels. While this approach can work for authors with a strong online presence and a dedicated fan base, it severely limits your book’s reach and potential sales.

Frequently asked questions #

Can I use the same ISBN for different formats of my book?

No, ISBNs are format-specific. You will need a separate ISBN for each format of your book, such as paperback, hardcover, e-book, and audiobook.

Do I need an ISBN for an e-book?

Yes, an ISBN is required for e-books if you plan to sell them through major retailers and distributors. Some platforms, like Amazon KDP, offer free ISBNs for e-books, but these come with limitations.

Can I transfer my ISBN to another publisher?

No, ISBNs are non-transferable. If you change publishers, you will need to obtain a new ISBN for your book.

How long does it take to get an ISBN?

The time it takes to obtain an ISBN can vary. In the US, you can purchase an ISBN online through Bowker and receive it immediately. In other countries, the process may take longer, and there may be additional requirements.