Amazon accounts for roughly 50–60% of all book sales in the US. KDP is free to set up, has no revision fees, and delivers your book to the largest single book marketplace instantly. For authors starting out, the complexity and cost of IngramSpark is rarely justified until you have a book you're confident in and an audience interested in buying physical copies outside Amazon.
IngramSpark's key advantage is access to the Ingram content network — the wholesale distributor used by bookstores and libraries worldwide. If you want your book orderable at Barnes & Noble, bookshop.org, or local independent bookstores, you need IngramSpark. KDP's 40% discount is too thin for bookstores to stock; IngramSpark's 55% wholesale discount meets their threshold. Libraries can also discover and order your title through Baker & Taylor and Ingram's library distribution channels.
Many authors use KDP for Amazon distribution (because Amazon de-prioritises IngramSpark-sourced titles on its own platform) and IngramSpark for everything else. This requires setting your KDP paperback price to be competitive on Amazon, and your IngramSpark price to allow the 55% wholesale discount while still netting a royalty. The practical approach: upload to KDP first, prove the book, then add IngramSpark once you know the book is worth the setup and revision costs.
Should I use KDP or IngramSpark for paperbacks?
Start with KDP. It's free, integrated with Amazon, and has no revision fees. Add IngramSpark once your book is final and you want expanded retail distribution. Never set IngramSpark to distribute to Amazon — KDP will always serve Amazon faster and at better margin.
Can I use KDP and IngramSpark for the same book?
Yes — but carefully. If you use both, block IngramSpark's Amazon distribution channel to avoid competing versions on Amazon. Use KDP for Amazon only and IngramSpark for all other retailers. Your ISBN must be the same on both (use a paid ISBN, not a free KDP one) for retail compatibility.
Does IngramSpark affect my Amazon rankings?
If IngramSpark distributes to Amazon alongside KDP, you may get two listings or a suppressed KDP listing. This is why the standard advice is to use KDP for Amazon distribution and explicitly disable IngramSpark's Amazon channel. Amazon will typically source from KDP for Prime eligibility anyway, so the IngramSpark Amazon channel adds no value and potential confusion.
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