This is one of the most searched questions in self-publishing, and the answer has become clearer as both platforms have evolved. KDP and IngramSpark are not really competitors — they solve different publishing problems, and the smartest approach for most self-published authors is to use both.

Amazon KDP (Kindle Direct Publishing) is Amazon’s self-publishing platform. When you publish a print book through KDP, it is listed on Amazon and fulfilled through Amazon’s print-on-demand network. There are no setup fees, no annual charges, and no cost to upload or update files. For books sold on Amazon, KDP generally gives authors strong royalty potential because Amazon is both the retailer and the fulfillment platform.

IngramSpark is the self-publishing platform from Ingram Content Group, one of the largest book wholesalers and distributors in the world. IngramSpark gives self-published authors access to bookstore, library, online retail, and international distribution channels that Amazon KDP does not fully replace.

The main difference between KDP and IngramSpark is distribution. KDP is usually best for selling print books on Amazon. IngramSpark is usually best for making a book available to bookstores, libraries, wholesalers, and non-Amazon retailers.

For most authors, the strongest setup is:

• Use KDP for Amazon print sales
• Use IngramSpark for bookstore, library, and wholesale distribution
• Use KDP for Kindle ebook sales
• Use Draft2Digital or direct uploads for non-Amazon ebook retailers

Bookstores rarely order books through Amazon because the wholesale terms are not usually attractive to independent retailers. IngramSpark lets authors set wholesale discounts and make books returnable, which makes the title easier for bookstores and libraries to consider.

There are also cost differences. KDP is generally simpler and cheaper to start with because there are no setup fees and Amazon can provide a free ISBN for print books. IngramSpark gives broader distribution, but authors should plan for ISBN costs, file revision fees, print costs, and distribution-related fees.

The best choice is usually not KDP or IngramSpark — it is KDP and IngramSpark together. KDP helps you maximize Amazon sales, while IngramSpark helps your book appear in the broader publishing and bookselling ecosystem.

One important note: if you publish the same print format through both KDP and IngramSpark, plan your ISBN strategy carefully. Many authors use separate ISBNs for each platform to avoid distribution conflicts and keep their publishing metadata clean.

For a self-published author who only wants to sell on Amazon, KDP may be enough. For an author who wants professional distribution, bookstore availability, library discovery, and stronger publishing credibility, IngramSpark is usually worth adding.

Sources:

• Amazon KDP Help Center
• IngramSpark Publisher Resources
• Alliance of Independent Authors: KDP Print and IngramSpark guidance