Two numbers decide whether your US passport is ready for Cambodia: six months of validity from your arrival date, and one full blank page. Get either wrong and the airline stops you in the United States, before you ever reach Phnom Penh.

Your US passport must be valid for at least 6 months from your date of entry into Cambodia and must have at least one full blank page for the entry stamp. Validity is counted from the day you arrive, not the day you apply for the eVisa, and the 6-month rule is enforced by the airline at your US departure gate. The eVisa is tied to the exact passport number on your application, so if your passport is expiring soon or short on pages, renew it first and then apply on the new book. Damaged passports and recently changed names are the two edge cases that catch Americans out most often.
Cambodia keeps its passport rules for US citizens short: your passport must be valid for at least 6 months from the day you enter, and you need at least one full blank page for the entry stamp. That is the whole standard. Almost everything that goes wrong for Americans is a version of one of those two numbers — a passport that runs out 5 months after arrival instead of 6, or a book so full of stamps that there is no clean page left.
The detail most travelers miss is where the rule bites. People assume an immigration officer in Phnom Penh checks the dates. By then it is far too late to matter. The 6-month validity rule is enforced by your airline at the US departure gate, because the carrier is liable if Cambodia turns you away on arrival. A passport that is one week short gets you stopped at LAX, SFO, or JFK — bag checked, boarding pass in hand, and no flight.
This guide covers exactly how the 6-month window is counted, how many blank pages you really need, what happens if your passport is damaged or recently renamed, and how renewal timing fits around your eVisa. For the bigger picture on whether you need a visa at all, start with our overview of whether US citizens need a visa for Cambodia, then come back here for the passport specifics. The full Cambodia visa for United States citizens hub ties the cost, documents, and timing together in one place.
Your US passport needs at least 6 months of validity remaining measured from your date of entry into Cambodia — not from the day you fill in the eVisa form, and not from the day you book your flight. This is the single number that trips up the most Americans, because it is easy to glance at an expiry date that looks comfortably in the future and miss that it lands inside the window.
Work it forward from your arrival date. If you land in Cambodia on March 1, 2027, your passport must be valid through at least September 1, 2027. An expiry of October 2027 is fine. An expiry of July 2027 is not, even though the trip itself is long over by then — the airline reads the rule as six clear months past the entry date, full stop. The math is unforgiving precisely because a human is not doing it; a gate-system check is.
Why six months and not the length of your actual stay? It is a regional convention across most of Southeast Asia, built so that no traveler is sitting in-country on a near-dead passport if plans slip or an emergency extends the trip. Cambodia applies it the same way Thailand, Vietnam, and Indonesia do. For Americans, the practical upshot is simple: if your passport expires anytime in the six months after your planned arrival, treat it as expired for this trip and renew before you do anything else.
If your passport is sitting right on the edge of the window, do not gamble on a sympathetic gate agent — there is no discretion built into the system. Renew first. We break the timing down in detail in our guide to the
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柬埔寨电子入境卡是独立于电子签证之外的一步,而且费用很低——只需支付$5美元,通过我们验证,填写14个字段,并在您起飞前7天内提交即可。以下详细说明了这笔费用包含哪些内容,为什么它不包含在您的签证费用中,以及它如何确保您在登机口顺利通行。
柬埔寨电子入境卡分为三个部分,共14个字段,需在抵达前7天内填写。以下是每个字段的具体填写内容,按表格要求顺序排列,另附日期格式的填写条,用于在自助服务终端识别美国旅客。
柬埔寨电子入境卡需要您提供三个部分共14项信息:身份信息、航班和停留时间,以及一份简短的海关申报单。以下是每个栏目所需填写的具体内容,以及填写前您需要准备的四样物品。

Cambodia requires at least one full blank page in your passport for the entry stamp. Not a half page, not the corner of a page already carrying a Thai or Vietnamese stamp — one clean page the officer can ink without crowding another country. For most Americans with a standard 28-page passport book and a few trips behind them, this is a non-issue. For frequent travelers, it is worth ten seconds of checking before you apply.
Open your passport to the visa pages — the ones after the photo page, headed for stamps and visas — and flip through. You are looking for at least one page with no stamps, no stickers, and no visas on either side that would crowd the new stamp. Cambodian Immigration stamps on a clean spread, so a page that is half-used on the back counts as used. If you are down to scattered gaps and edge slivers, you are effectively out of pages.
A quick reality check on the standard US passport: the regular book has 28 pages, of which around 17 are usable visa pages once you set aside the cover, signature, and endorsement pages. The 52-page book — what the State Department now issues by default in many cases, and which you can request at no extra cost — gives you far more runway. If you travel often and you are renewing anyway, opt for the larger book and you will not think about pages again for years. To see how the blank-page rule sits alongside everything else you need, the Cambodia visa requirements for US citizens checklist walks through exactly what counts as a clean page.

Two passport conditions cause more last-minute scrambles for Americans than expiry or pages combined: physical damage, and a name that no longer matches across documents. Both are fixable, but only if you catch them before you apply, because your eVisa locks to the passport you submit.
A passport with water damage, a torn or detached cover, a bent or delaminated photo page, or pages coming loose can be refused by either your airline or Cambodian Immigration — even if the dates and pages are fine. Normal wear is accepted; a soft cover and a few dog-eared corners will not stop you. Significant damage will. If the machine-readable zone at the bottom of your photo page is scuffed, smeared, or peeling, that is the part scanners read, and damage there is the most likely to cause a problem. When in doubt, renew — a damaged passport is treated as invalid, not as a lesser version of valid.
The name on your eVisa application must match your current passport exactly — character for character, including middle names and any hyphenation. If you married and changed your name but your passport still shows your maiden name, apply in the name on the passport. If you have already updated your passport, apply in the new name and travel on the new book. Do not mix the two, and do not apply in a name that matches your driver license but not your passport. The eVisa is checked against the passport, not against any other ID.
The unifying rule behind both edge cases: your eVisa is tied to the exact passport number you enter on the application. If you renew after applying — even for the same person, same name — the old eVisa is attached to a passport you are no longer carrying, and that mismatch can stop you at the gate. So renew first, then apply on the new passport number. The same principle drives every item on our Cambodia eVisa documents checklist for Americans, where the passport scan has to match the data you type.

If your passport fails any of the checks above, renew it before you apply for your eVisa — not after, and not in parallel. The order matters because the eVisa attaches to the passport number you submit, and a brand-new passport carries a brand-new number. Renew, receive the new book, then apply on the new details.
In 2026, standard US passport renewal runs about 4 to 6 weeks once the application is received, with expedited service at roughly 2 to 3 weeks for an added fee. Online renewal is available for many eligible adults, which can shave processing time, but the realistic planning number is still weeks, not days. If you have a trip within a couple of months and a passport that needs work, treat the renewal as the long pole and book travel around it.
Once your passport clears all five checks — six months of validity, a clean page, sound condition, the right name, and a number you will keep — the eVisa itself is the easy part. It is approved in 3 business days and delivered as a printable PDF by email, with US-timezone support if anything needs a second look. You can start your Cambodia eVisa application as soon as your passport is squared away, and there is free resubmission if Immigration flags a correction.

Run the full check in half a minute. Open your passport to the photo page and read the expiry date — is it at least six months past your planned arrival in Cambodia? Flip to the visa pages — is there at least one fully clean page? Look at the book itself — any water damage, a loose cover, or a scuffed strip across the bottom of the photo page? Check the name — does it match exactly what you will type on the eVisa? If all four are yes, you are ready to apply on this passport.
If any answer is no, the fix is the same: renew first, then apply on the new book. It is the single piece of advice that prevents the most stressful version of this — a paid eVisa attached to a passport you can no longer use, discovered at the airport. For everything else around eligibility and entry, the eligibility overview and the full visa hub linked above are the next two stops.
Next steps and related reading for Americans: apply for your Cambodia eVisa once your passport clears the check, read the US passport 6-month rule guide for the validity detail, and confirm your full document set with the US citizen visa requirements checklist before you start.