Visa exemption
Oversea Vietnamese and foreigners whose husbands, wives and children are exempt from visa requirements to enter Vietnam and are allowed to stay for not more than 90 days.
In order to be granted visa exemption certificates at Vietnamese representative offices abroad, overseas Vietnamese need conditions:
Foreign-issued permanent residence certificate (PRC) with the validity of at least six months since the date of entrance.
Visa exemption paper (VEP) is granted by Vietnamese appropriate authorities.
Those who expect to stay more than 90 days must apply for visa according to current stipulations before their entrance.

Bilateral visa exemption agreement
Citizens of Thailand, Malaysia, Singapore, Indonesia and Laos holding valid ordinary passports are exempt from visa requirements and are allowed to stay for not more than 30 days; Philippines is allowed to stay for not more than 21 days.

By February 2011, citizens of China, Kyrgyzstan, North Korea, and Rumania holding valid ordinary passports for official mission. Citizens of following countries holding valid diplomatic or official passports are exempt from visa requirements including: Argentina, Afghanistan, Albania, Algeria, Azerbaijan, Bangladesh, Belarus, Brazil, Brunei, Bulgaria, Cambodia, Chile, China, Croatia, Cuba, Czech Republic, Dominica, Ecuador, France, Hungary, India, Indonesia, Iran, Iraq, Japan, Kazakhstan, Kyrgyzstan, Laos, Malaysia, Mexico, Moldova, Mongolia, Montenegro, Morocco, Mozambique, Myanmar, Nicaragua, North Korea, Pakistan, Panama, Paraguay, Peru, Philippines, Romania, Russia, Serbia, Singapore, Slovakia, South Africa, South Korea, Spain, Sri Lanka, Switzerland, Thailand, Tunisia, Turkey, Ukraine, Uruguay, Uzbekistan, Venezuela.

Unilateral visa exemption
Visa with 30-day validity is exempted for officials from ASEAN secretariat holding different kinds of passports.
Citizens of Sweden, Norway, Denmark, Finland, Japan and South Korea holding different kinds of passports are exempt from visa requirements and are allowed to stay for not more than 15 days.
Visa application
Citizens of other countries and those not subjected to visa exemption above are required to get an entry visa before departure or an approval letter for a visa on arrival (the visa issued on arrival at Vietnam International Airports)
To obtain your entry visa you have to apply to any Vietnam Embassies and/or Consulates worldwide.
Tourist visas are valid for a single 30-day stay and allow visitors to enter and exit Vietnam at Hanoi, HCMC and Danang airports or at any of land borders, shared with Cambodia, China and Laos.
Processing a tourist-visa application typically takes four or five working days in countries in the West.
If you plan to spend more than a month in Vietnam, or if you plan to exit Vietnam and enter again from Cambodia or Laos, you just need to arrange a multiple-entry visa.

Documentary requirements for a visa
Passport:
You must provide your actual signed passport, including one copy of the personal information page of your passport. Your passport must:
Be valid for the next six months
Have at least one blank visa page (amendments and endorsement pages cannot be used to fulfill this requirement)
Not be frayed, torn, separating, or altered in any other way
Photographs
You must provide at least 2 color-passport-type photograph. The photograph must:
Be printed on photo paper
Be two inches by two inches
Have a white background
Have been taken within the last six months
Visa Application Form
You must provide one completed visa application form. The application form must:
Include answers for all fields
Display your full name as it appears in your passport
Be signed
The visa application form may vary from Embassy to Embassy, so you need to take the form from the specific Embassy where you will obtain your visa. Submit this filled form with your original passport, 2 or 3 photos, accompanied by the visa fees. It will take between 4 to 10 days depending on your country of origin

Visa fee
Visa fee ranges from US$45 to US$85 if application is sent directly to the Embassy or US$25-55 if your visa has been pre-approved. This fee depends on The Embassy and Type of visa required.

If there is no Vietnam Embassy or Consulate in your country, or if you just want to make Vietnam part of a multi-destination trip, then Visa on Arrival is the best option.
This is most likely the easiest way to obtain your visa without having to chase down embassies, consulates and the like prior to your trip. The entry visa will be stamped on your passport at the Visa On Arrival Desk at the International Airport in Vietnam. Then you can pass through the Immigration checking point. With this type of visa, you only can enter the country by air.

Source: customvietnamtravel  

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