The difference between a passport book number and a passport number is straightforward once you know what each one does: the passport number identifies you as the traveler and is the number airlines, border officers, and visa applications actually use, while the passport book number is an internal tracking code the issuing government stamps on the blank booklet before it’s ever tied to a person. Many passports don’t display a book number at all.
What Your Passport Number Is
The passport number is the primary identifier linking the document to you. Airlines, border agents, visa officers, and foreign governments all use it to verify your identity and travel authorization. It appears on the data page and is repeated throughout the booklet, usually printed or perforated at the bottom of each interior page.
You get a new passport number every time you receive a new passport. The old number cannot be reused, even if the previous passport was lost or stolen.1U.S. Department of State. Frequently Asked Questions about Passport Services Current U.S. passports (the Next Generation design issued since 2021) use a letter followed by eight digits.2U.S. Department of State. Information about the Next Generation U.S. Passport Older U.S. passports used a purely numeric format.
What the Passport Book Number Is
The passport book number is an internal identifier the issuing government assigns to the physical booklet, typically before it’s personalized with anyone’s information. It works something like a serial number on a blank check: the government prints thousands of blank booklets, and the book number lets the agency track each one from the printing facility through to the office where it gets personalized and handed to a traveler.
Not every passport has a visible book number. The U.S. State Department’s guidance is plain on this: “You may or may not have a Passport Book Number on your passport.”3U.S. Department of State. DS-160 Frequently Asked Questions Where it does exist, its placement and format vary. Some passports print it on the inside back cover, others embed it on interior pages, others place it near the data page. Several European countries, including France, Germany, and Sweden, include a book number in at least some versions of their passports.
The book number plays no role in identity verification at a border. No airline asks for it, and no immigration officer scans it when you enter a country. It exists for the agency that manufactured and distributed the booklet.
The Two Numbers Side by Side
- Passport number: Identifies the person. Changes every time you get a new passport. Used for travel, visa applications, and border crossings. Printed on the data page and throughout the booklet.
- Passport book number: Identifies the physical booklet. Assigned during manufacturing, before the book is linked to anyone. Used for inventory control by the issuing government. May not be visible or present at all, depending on your country’s passport design.
Both are unique identifiers, but they answer different questions. The passport number answers who the traveler is. The book number answers which specific blank booklet the passport started as.
The DS-160 Field That Prompts the Question
Most people search for this comparison because of the DS-160, the online application required for most U.S. nonimmigrant visas. The form includes a field labeled “Passport Book Number” with no on-screen explanation of what it wants.
The State Department defines the field as “commonly called the inventory control number” and acknowledges that your passport may or may not contain one.3U.S. Department of State. DS-160 Frequently Asked Questions If you can’t find a separate number on your passport beyond the main passport number, select “Does Not Apply.” The DS-160 allows that answer for any question that doesn’t fit your situation.
If your passport does have a book number, it will be a separate alphanumeric string from your main passport number, usually in a different location on the booklet. When in doubt, the State Department recommends contacting your passport issuing authority rather than guessing. Entering the wrong number, or putting your passport number in the book number field, creates unnecessary complications.
If Your Passport Is Lost or Stolen
Report a missing U.S. passport using Form DS-64. The form asks for the passport number and issue date if you have them, but it does not include a separate field for the book number.4U.S. Department of State. Statement Regarding A Valid Lost or Stolen US Passport or Card (DS-64) The passport number is what matters for canceling the document and flagging it in international databases, and the old passport number will never appear on your replacement.1U.S. Department of State. Frequently Asked Questions about Passport Services
Passport Cards Don’t Have Book Numbers
One boundary worth flagging: U.S. passport cards, the wallet-sized alternatives valid for land and sea travel to Canada, Mexico, the Caribbean, and Bermuda, have their own passport number but no book number, because there is no booklet involved. If you hold both a passport book and a passport card, each has its own separate passport number.4U.S. Department of State. Statement Regarding A Valid Lost or Stolen US Passport or Card (DS-64)