米国からの旅行者は、カンボジアの電子ビザをどれくらい前に申請すべきでしょうか？

The early edge: do not let your eVisa expire on the shelf

This is the trap that catches careful planners. You book your flights in January for an April trip, you are the kind of person who likes loose ends tied off early, so you apply for your eVisa the same week. The visa is issued in January. It is valid for 3 months from issue. By the time April arrives, it has expired — and you find out at the airline gate, when boarding is denied.

The rule to memorize: the Cambodia eVisa validity clock starts on the issue date, not on your arrival date. Three months from issue is the window in which you must enter Cambodia. Once you enter, you get a 30-day single-entry stay. But the entry itself has to happen inside that 3-month band, or the visa is dead and you apply again from scratch — and pay again.

So the earliest you should ever apply is exactly 3 months before your planned arrival, and even that is cutting the front edge fine because it assumes you travel on the last possible day. A more comfortable earliest is around 6 to 8 weeks out. That keeps a buffer on the front of the validity window in case your trip slips a few days, while still being far earlier than you need to be. For most people, the practical takeaway is: there is no reward for applying months ahead, and there is a real penalty.

One related point that confuses Americans: an "intended arrival date" on the application is not a lock. The form asks for it, but the visa is valid for any single entry within the 3-month window, not just the day you typed. So if your plans shift by a week after you apply, you do not need to redo anything — as long as your real arrival still falls inside the 3 months from issue.

Weekends, Cambodian holidays, and US holidays

The 3-business-day promise is measured in Cambodian business days, and that distinction matters more than most US travelers realize. Saturdays and Sundays do not count. Cambodian public holidays do not count. A US federal holiday like Thanksgiving or the Fourth of July has no effect on the processing clock at all, because the file is being reviewed against Cambodian Immigration time, not American time.

Cambodia observes a longer list of public holidays than the US, and several of them run multiple days. Khmer New Year in mid-April, Pchum Ben in late September or early October, and the November Water Festival are the big multi-day stretches. If your application lands right before one of those, your 3 business days can stretch across a full calendar week. Our guide to how Cambodian weekends and holidays affect processing for Americans maps the dates worth planning around.

There is also a time-zone wrinkle in your favor and against you. Cambodia is roughly 11 to 14 hours ahead of the continental US, depending on your time zone and daylight saving. Submit on a Tuesday evening from California and it is already Wednesday in Phnom Penh, so your clock may start a day "earlier" than the calendar on your wall suggests. The flip side: a Friday-night submission from the US East Coast is effectively a Saturday in Cambodia, so processing realistically begins Monday.

The practical move is to submit early in your week rather than late, and to add an extra buffer day or two if your application window overlaps a major Cambodian holiday. If you are traveling during one of the big festival periods, our guide to Cambodia visa processing during the holiday season for Americans is worth a read before you lock your timing in.

The late edge — and where the e-Arrival Card fits

If two to four weeks is the comfortable band, what actually happens when you cut it closer? The honest answer is that a clean application submitted a week out is usually fine. The risk is not the processing itself — it is what happens if your file gets flagged for a correction and you have no slack left. A photo re-upload that would be a shrug with two weeks in hand becomes a sprint with two days in hand.

There is no extra charge to fix a flagged file, and the 3-business-day clock keeps running once you re-upload — but the correction still needs Cambodian business hours to clear, and you cannot manufacture more of those at midnight before a 6 a.m. flight. If you genuinely have only days, do not panic, but do read our realistic last-minute Cambodia visa timeline for US citizens so you know exactly what is and is not possible on a tight clock.

Now the piece that trips up otherwise well-organized travelers: the e-Arrival Card is on a completely different clock from the visa, and it runs the opposite way. The visa you want done early-ish. The e-Arrival Card you cannot do early. It is a separate mandatory step for every air arrival — 14 fields, three sections, a $5 USD fee verified through us — and it can only be submitted within the 7 days before you arrive in Cambodia.

So the two tasks slot into different parts of your countdown. Get the visa squared away 2 to 4 weeks out. Then set a reminder for the final week to file the e-Arrival Card. Trying to do the e-Arrival at the same time as the visa simply will not work — the system rejects a submission made more than 7 days ahead. Plan for both as separate calendar entries and you avoid the most common 2026 trip-stopper at the kiosk.

Timing by scenario: when your dates are firm, soft, or imminent

The 2-to-4-week rule is the default, but real trips do not always fit a default. Here is how the timing shifts for the situations American travelers actually find themselves in.

Dates locked, flights booked, trip more than a month out: apply at the 2-to-4-week mark and do nothing before that. You gain nothing by going earlier and you start nibbling at your validity window. Put a reminder in your phone for three weeks before departure and forget about it until then.

Trip booked far ahead — say four to six months out: wait. Do not apply yet. Set a reminder for roughly 8 weeks before your arrival date, which keeps you safely inside the 3-month validity window with margin to spare. This is the single most common timing mistake we see from organized planners, and it is entirely avoidable.

Dates still soft, you know the month but not the day: you can apply once you are reasonably confident your arrival will fall inside the next 3 months. Because the "intended arrival date" is not a hard lock, a little drift in your real travel day is fine, as long as the actual entry stays inside the validity window. If your plans are genuinely up in the air beyond 3 months, wait until they firm up.

Putting your timeline together

Here is the whole countdown in one line. Around 2 to 4 weeks before you fly, apply for your eVisa — Tourist $80 USD, Business $90 USD, both approved in 3 business days and delivered as a printable PDF by email, both with free resubmission if Immigration flags a correction and US-timezone support behind them. Then, in the final 7 days, file your e-Arrival Card. That is the entire timeline. If you want the deeper version of the approval math, our guide to how long the Cambodia eVisa takes for Americans breaks down the 3-business-day clock.

A few related decisions worth settling at the same time you pick your application date. If you are still figuring out the best day and hour of the week to submit, our note on when to apply for the best Cambodia eVisa timing for US citizens covers the time-zone edge in detail. And if your departure is genuinely close, do not guess — the last-minute timeline guide for US citizens spells out what a tight clock actually allows.

Next steps and related reading for Americans: apply for your Cambodia eVisa when your arrival falls inside the next 3 months, bookmark our Cambodia visa hub for US citizens as the single canonical reference, skim the FAQ on Cambodia visa processing time for quick answers, and use our glossary of Cambodia visa terms to decode any acronym in this guide.