How to Get a Library of Congress Control Number (LCCN) — and Why It Matters

If you’re publishing a paperback or hardcover in the U.S., you may be eligible for a Library of Congress Control Number (LCCN). This isn’t the same as an ISBN, and it doesn’t guarantee your book will end up in the Library of Congress. But it does make your book easier to catalog, more appealing to libraries, and more professionally presented. Here’s how it works.

What Is an LCCN?

A Library of Congress Control Number (LCCN) is a unique identifier created by the Library of Congress to help libraries and booksellers catalog books before they’re published. It’s not required for publication — but having one improves how your book is classified in databases and library systems.

It’s particularly useful if you’re hoping your book will be acquired by libraries, schools, or academic institutions. It’s also one of those small, professional touches that can quietly raise the credibility of your print edition.

Note: An LCCN does not guarantee your book will be housed by the Library of Congress. It simply creates a catalog record to help libraries classify it.

Why Should Indie Authors Get One?

• Easier access to libraries: An LCCN helps libraries catalog your book correctly.
• Academic and professional credibility: Schools and libraries are more likely to consider books with LCCNs.
• Retailer and wholesaler readiness: Some distributors and bookstores prefer books with LCCNs for cataloging purposes.

Who Can Apply?

You can apply if:

• You’re a U.S.-based self-publisher or small press
• You’re publishing a physical book (paperback or hardcover)

You cannot apply if:

• You’re publishing only in ebook format
• You live outside the U.S. without a U.S.-based publishing address

How to Apply for an LCCN

You must apply through the Preassigned Control Number (PCN) Program before your book is published.

1. Go to the PCN Program page: https://loc.gov/publish/pcn/
2. Create an account and complete the publisher application. Approval usually takes a few business days.
3. Once approved, log in and apply for a new LCCN by submitting your book’s title, author name, publisher name (your name or imprint), ISBN, and anticipated publication date.
4. Within 1–2 weeks, you’ll receive your LCCN by email.
5. Place it on your copyright page before printing your book.

After You Receive Your LCCN

• Add it to your copyright page (usually below the ISBN)
• Print and distribute your book
• If requested, send a copy of the finished book to the Library of Congress

You can find the full LCCN submission requirements here: loc.gov/publish/pcn/about

Notes for International Authors

Other countries have similar cataloging and legal deposit systems:

• United Kingdom: The British Library operates under a legal deposit system that requires publishers to submit a copy of every printed publication.
• Germany: The Deutsche Nationalbibliothek requires submission of print materials for cataloging and preservation.
• Italy: The Biblioteca Nazionale Centrale in Rome and Florence oversees a legal deposit system for national cataloging.

Final Notes

LCCNs are free and relatively quick to obtain — but only for U.S.-based publishers of print books. This is not the same as applying for CIP data (Cataloging-in-Publication), which is more complex and generally reserved for traditional publishers or academic presses.

LCCNs won’t sell books — but they can open doors in library and academic markets, and they’re a simple way to make your book more catalog-friendly. If you’re publishing a print edition in the U.S., take a few minutes and apply.