You booked the flight months ago. Then the passport was reissued — a new booklet with a new number. The trip is still on, but the document the airline has on file is no longer the document you will travel with. What actually needs to change?
The short answer is reassuring: the ticket itself usually does not. A reissue alone changes the document number, not the traveler's name, and the name is what the ticket is built around. What must be updated is the passport number attached to the reservation — the advance data the airline sends to border authorities ahead of the flight.
Korea's passport office confirms that a reissued passport always carries a newly generated number, and the old number cannot be kept. And for the United States, a new passport also means a new ESTA: federal rules require a new travel authorization whenever a traveler is issued a new passport. Update the number, renew the ESTA, and the same booking still flies.
Information checked: October 29, 2026.
What Actually Changes When Your Passport Is Reissued?
Only the document changes. A reissued Korean passport is a new booklet with a newly generated passport number — the Ministry of Foreign Affairs' passport FAQ states plainly that the previous number cannot be assigned again. Your name, date of birth, and nationality stay the same, unless the reissue itself was made because one of those details changed.
The old passport is invalidated when the new one is issued. On request, the old number can be printed in the new passport's endorsement section as a reference — but that note does not keep the old document, or its number, valid for travel. For every booking and authorization, the number that counts is the new one.
Does the Ticket Name Have to Change Too?
No — not if the name itself is unchanged. The U.S. Transportation Security Administration's Secure Flight program matches passengers by full name, date of birth, and sex against watchlists, and the name on the reservation must match the government-issued ID used for travel. The passport number is not part of Secure Flight data; it travels separately, as advance passenger information sent to Customs and Border Protection.
So a number-only change is not a name correction, and it does not require a ticket reissue or a new booking. The exception is a reissue that came with a legal name change: then the ticketed name no longer matches the ID, and the name on the ticket must be corrected with the airline. That is a different process from updating a document number.
Where Does the New Passport Number Go?
Airlines must send passport details to border authorities before departure. For flights to the United States, that advance passenger information (APIS) includes the passport number, the country that issued it, and its expiry date, and it is checked against CBP databases before the flight.
Asiana Airlines confirms how this plays out at check-in: passport information entered during online check-in is sent to U.S. Customs and Border Protection in real time, and no boarding pass is issued for a passport that has not been approved through ESTA. If the number on file is the old, invalidated one, check-in itself can stall — which is why the update belongs in the reservation, not left until the airport.
How Do You Update the Number on a Booking?
Contact the airline that issued the ticket and replace the passport details on the reservation — through its manage-booking page or app, or through its call center. Asiana Airlines' own pages confirm that passport information can be edited through the check-in menu, that passenger information can be edited even after online check-in via the change check-in menu, and that wrong passport information can also be corrected at the airport counter.
Do it as early as you can, as soon as the new passport is in hand, and re-check the reservation afterwards to confirm the new number — not the old one — is showing. Sourcing limit: only Asiana's update process was checked directly for this article; other airlines' menus, apps, and cutoffs vary, so confirm the exact steps with the airline that issued your ticket. No fee for a passport-number update was verified for this article, and none is stated here.
Do You Need a New ESTA With the New Passport?
Yes. Under the federal ESTA regulation, 8 CFR 217.5, a new travel authorization is required whenever a traveler is issued a new passport. An ESTA is valid for two years from issuance, or until the passport expires — whichever comes first — and it is tied to the specific passport it was approved under. The old ESTA does not carry over to the new document, even if it is still within its two years.
Apply for the new ESTA with the new passport's details before you travel, and confirm the approval before leaving for the airport — Asiana notes that no boarding pass is issued for a passport without ESTA approval. Sourcing limit: this article covers ESTA travelers only. Rules for a U.S. visa placed in an old passport were not verified for this article, so travelers on a visa should check with the U.S. embassy or consulate rather than assuming the same steps apply.
What If You Only Notice at the Airport?
It can still be fixed, but the margin shrinks. Asiana confirms that incorrect passport information can be corrected at the airport counter — so a wrong number on the reservation is not automatically the end of the trip. What cannot be fixed at the counter is a missing ESTA approval for the new passport, since the boarding pass cannot be issued until that approval exists.
The practical order, then, is: update the passport number on the reservation as soon as the new passport arrives, apply for a new ESTA with the new details, and verify both — the number on the booking and the ESTA approval — before check-in opens. A two-minute check at home beats a counter conversation on departure day.
Official Sources
U.S. Transportation Security Administration — Security Screening (Secure Flight)
https://www.tsa.gov/travel/security-screening
Asiana Airlines — Online Check-in (passport information and APIS)
https://m.flyasiana.com/C/US/EN/contents/online-check-in
Electronic Code of Federal Regulations — 8 CFR 217.5, Electronic System for Travel Authorization
https://ecfr.io/Title-8/Section-217.5
Republic of Korea Ministry of Foreign Affairs — Passport FAQ (reissued passport numbers)
https://www.passport.go.kr/home/kor/board.do?menuPos=69&searchValue3=29
This article reflects U.S. and Korean passport rules available on October 29, 2026. Rules and airline procedures can change — confirm the current requirements with your airline and on the official CBP and passport-office websites before you travel.