The passport biodata page is the identity page of your passport: it carries your photo, your personal details, your passport number, the issue and expiration dates, the issuing authority, your signature line, and a block of machine-readable text at the bottom. Its layout follows an international standard set by the International Civil Aviation Organization (ICAO), so the same information sits in the same place whether the booklet was issued in the United States, Germany, or Japan.
What Appears on the Page
Every field on the page exists so a border officer can confirm, in seconds, that the person standing at the counter matches the document. You’ll find:
- A recent standardized photograph of the holder
- Full legal name, surname and given names, printed as they appear in official records
- Date of birth in a standardized format
- Place of birth
- Nationality
- Sex, shown as a single letter (F, M, or X in countries that recognize a non-binary marker)
- Passport number, a unique alphanumeric identifier for that specific booklet
- Date of issue and date of expiration
- Issuing authority
- Signature line
The signature is the one field the government leaves to you. After the passport arrives, you sign the signature line in blue or black ink. For a child under 16, a parent prints the child’s full name on the signature line, signs their own name beside it, and notes the relationship to the child.1Travel.State.Gov. After You Get Your New Passport
In current U.S. passports, most of that information isn’t printed in ink. The next-generation booklet issued since 2021 uses a polycarbonate data page with laser-engraved personal data, which etches your details directly into the plastic and makes them very hard to alter without visibly damaging the page.2Travel.State.Gov. Information About the Next Generation U.S. Passport
The Machine-Readable Zone at the Bottom
The block of capital letters, numbers, and angle brackets running across the bottom of the page is the Machine-Readable Zone, or MRZ. Scanners at passport control read it optically, which is why border officers rarely need to type anything from your booklet.
On a standard passport book, ICAO’s TD3 size, the MRZ is two lines of OCR-B text, each exactly 44 characters.3ICAO. Doc 9303 Machine Readable Travel Documents – Part 1 The first character is the letter P, marking the document as a passport.4ICAO. Doc 9303 Machine Readable Travel Documents – Part 4 Then comes a three-letter issuing country code (USA, GBR, DEU), followed by the holder’s surname and given names separated by double angle brackets. The second line compresses the passport number, nationality, date of birth, sex, and expiration date, along with a handful of single-digit check digits. Those angle brackets scattered through the code are filler: they stand in for spaces and pad unused positions so each line hits exactly 44 characters.
The check digits are what make the zone tamper-evident. Each one is mathematically derived from the field next to it. If a character in the passport number or the date of birth has been altered or misread, the digit won’t recalculate correctly and the scanner flags the mismatch. No database lookup is required, which is what keeps the check fast enough for high-volume border crossings.
Security Features and the Electronic Chip
Beyond laser engraving, biodata pages carry security artwork, holographic overlays, microprinting, and elements visible only under ultraviolet light. Governments deliberately keep the full list confidential so counterfeiters can’t work from a checklist.
More than 180 countries now issue e-passports, marked by a small gold chip symbol on the front cover. The chip stores the same information printed on the biodata page along with a biometric identifier; for U.S. passports, that biometric is a digital photograph of the holder.5Homeland Security. e-Passports An officer can compare the chip’s photo, the photo on the page, and the face in front of them.
The chip isn’t broadcasting your details to anyone with a scanner. A protocol called Basic Access Control requires a reader to optically scan the MRZ on the biodata page first, using it to generate the key that unlocks the chip. If the booklet stays closed, the chip stays silent.5Homeland Security. e-Passports
Damage That Makes the Page Unusable
Normal wear is fine. A slight bend from a back pocket won’t cause problems. Certain damage will, and airlines and border officers have broad discretion. The State Department says you need a replacement passport if the biodata page or booklet shows any of the following:
- Water damage, including mold or stains
- A significant tear
- Unofficial markings on the data page
- Visa pages that have been torn, ripped, or cut out
- A hole punch, other than one made by the issuing authority to cancel the document
The unofficial-markings rule catches people out. A child’s crayon line across the page, a coffee ring, or a stray pen stroke can raise a tampering question. The State Department warns holders not to write on any page besides the signature line and the emergency contact section.1Travel.State.Gov. After You Get Your New Passport A scratched or obscured MRZ is a separate problem: even if the human-readable text above still looks correct, damage to the code can block automated processing and send you to secondary inspection.
Check the Page the Day It Arrives
Read every field on your biodata page against your source documents the day the passport arrives. If you find a misspelled name, a wrong date of birth, an incorrect sex marker, missing data, crooked printing, or discoloration, you can get it corrected at no charge while the passport is still valid.7Travel.State.Gov. Change or Correct a Passport The correction is done by mail using Form DS-5504, along with the current passport, a color passport photo, and evidence of the error such as a birth certificate.
The one-year window matters. Report the error within a year of the original issue date and you get a fresh passport valid for the full 10 years (5 for a minor). Report it later and the replacement expires on the same date as the original.8U.S. Department of State. Application for a U.S. Passport – Form DS-5504 The correction itself is free; expedited processing costs extra.9Travel.State.Gov. Passport Fees
The Expiration Date Isn’t Always the Real Deadline
The date printed on your biodata page tells you when the booklet expires, but many countries require the passport to remain valid for at least six months beyond your planned stay. The United States applies this rule to most foreign visitors, though citizens of certain exempt countries only need validity through their intended departure date.10Customs and Border Protection. Six-Month Passport Validity Update
The trap is that the passport isn’t technically expired. You might have three months left and assume a one-week trip is fine, then find the airline won’t let you board. Check the entry rules for your destination before booking, and read the expiration date on your biodata page against them.