Citizens from most nationalities are required to get a visa to Cambodia before entering. Only citizens coming from Laos, Malaysia, Philippines, Singapore, Vietnam, Thailand and Indonesia are exempt from this requirement.
Fortunately, the Cambodian government launched an electronic visa or e-visa in 2006, which enables tourists to apply for their visas online (excluding those coming from Afghanistan, Algeria, Arab Saudi, Bangladesh, Iran, Iraq, Pakistan, Sri Lanka, Sudan and Nigeria).
Cambodia Visa can also be obtained through of this link´s site and in the Cambodia Visa page of Ivisa.com
Passport valid for at least 6 months from the date of entry to Cambodia
One recent 2 x 2 passport type photograph in color, front view and with a plain/white background.
Proof Of Departure – Computer generated flight itinerary from the airline or a travel agency or copy of airline tickets.
E-visas for Cambodia can only be issued for tourism purposes. They last 3 months, are valid for a single entry, and allow travelers stay up to 30 days in the country.
E-visas can ONLY be used at the main entry ports of Cambodia namely: Phnom Penh and Siem Reap International airports; and Cham Yeam, Poi Pet and Bavet border check points if visitors are entering the country by land. If you arrive by ship, you need to contact the Cambodian Embassy for the correct visa.
An e-visa takes from 24 hours to 3 days to be processed. Once approved, the applicant receives an email with the e-visa attached in a PDF file.
The e-visa must then be printed and presented at the border crossing in Cambodia, where an official will place a stamp inside the traveler’s passport. Visitors will also be given an exit visa, which they must keep in order to leave Cambodia.
: The US State Department strongly encourages American citizens planning international travel to register with the US Embassy(s) in the countries they plan to visit. You can do that by visiting iVisa.com