A regular tourist visa for Vietnam is available for 1 or 3 months. Once you have a visa it’s possible to extend your visa in the country and save yourself the time and money of doing a visa run. While there is no published official amount of time that you can extend your visa in-country, visitors have been known to be questioned when extending for the third or fourth time. Thus it is a good idea to leave the country and restart a new visa.
If you need to do a visa run from Ho Chi Minh City here are the best options.
Bus To Phnom Penh
By far the cheapest option is to get the bus to Phnom Penh in Cambodia. Numerous buses leave throughout the day from the Pham Ngu Lau area.
Just go to any one of the many travel agents on Pham Ngu Lau and and buy a ticket there. Tickets are $12USD and the trip takes 6-7 hours, depending on traffic and the queue at the border.
Some buses have wifi and the road between the two cities is mostly flat straight road.
If you are returning by bus then you will need to get a visa in Phnom Penh as the online visa service is not accepted at land border crossings. Go to a travel agency in Phnom Penh and they will arrange a new Vietnam Visa for you. This usually takes 2-3 working days. If you don’t want to wait around in in Phnom Penh then you could also apply in Sihanoukville which is about 4 hours away. Thus you can get in some beach while waiting for your visa.
The cheapest flights out of Ho Chi Minh City are almost always the low cost airlines, with the closest cities being Bangkok, Kuala Lumpur, and Singapore.
It is also worth checking Skyscanner to see if there are any good deals going on with the full service airlines.
When flying back you need to arrange your visa online first.
There is no railway between Vietnam and Cambodia yet. There are plans for a Ho Chi Minh City – Phnom Penh railway, but that is years away from being a reality.