We will need to be in touch with "home" while we are in Vietnam this winter. Is the best option to take an unlocked GSM phone and buy a Vietnam SIM card when we arrive? Is there a particular provider that's best? Does anyone know what it costs to call the US from VN?

I can't help much, but I can tell you that my US (AT&T)provider worked perfectly throughout Vietnam. However, due to a health issue my dad had while I was there, I did need to connect with folks in the US outside of texting, and it was expensive!! Call your provider, they can tell you what the per minute charges are.

Jen, that's what we did when we were in Egypt two years ago, so it's good to know it's a viable alternative (also AT&T). I know the per minute price - $1.99 per minute if we sign up for World Connect - so maybe I'll just do that. I don't expect to use data roaming at all, so it would just be calls to and from the US (by the time we go my dad will be almost 92 -- I think we should be available by phone!) and texting to an from my daughter, who will be working at a ski area in California.

You are right, the best option is to take an unlocked phone and to buy a prepaid Sim card. I always buy mobi cards, but there are different providers. I think it doesn´t matter, which one you buy. The costs are very low. You can buy the the card in internet and phone shops, but the easiest way is to ask the employees of your hotel.

Ok, don't laugh at me (well, you can). What is an unlocked cell phone? Can I have my Verizon cell phone unlocked? If I buy a Sim card can I use it for calls within vietnam -- e.g. to the travel agent if there is a problem with flights, hotels?

carole.. most of our usa phones have a lock on them to the servicer you subscribe to...

i have an AT&T phone and i could never successfully get it unlocked, so i bought a new phone in asia....

a thai sim card only costs about 30 B and then you just load it with minutes at any 7/11... for vn i suspect you do the same..

Just a smile. If you don´t have a unlocked one you can buy a simple Nokia for around $25 in Vietnam.

Before I left for Vietnam, i called T-mobile and asked for instructions to unlock the phone. They email the instruction and it was very simple. I heard you can get the instruction from Google too but I have not tried it.

We have an unlocked phone (use it on all international trips) -- we got one on ebay, and then AT&T unlocked one of our old Razr's for us. So that parts not an issue. We'll take that with us and plan to buy a SIM there. We'll also be in Siem Reap and Hong Kong -- does the same apply there?

CFW, most Verizon phones cannot be used internationally because they don't use a SIM card at all -- they're on a different system (CDMA instead of GSM). You'd have to find out if your particuar phone is GSM, and then ask if they'll unlock it for you.

THis is a great guide! Thanks for posting.

I agree - the guide is excellent!

For Belgian readers:
Buy a SIMcard and call Europe at a rate of around 25 eurocents/minute !
We used Viettel but next time we'd take Mobiphone because of the nicer and more informative website.

As an aside, all the hotels we stayed in had internet connection and many had free computers either in the lobby or the room. It was easy to communicate with home daily.

Get a new cheap fone about 200-400 Vietnamese and a new sim card only 60 Vietnamese then enjoy it.

I traveled Vietnam for a year. I paid $3/month with Skype and I was able to call anyone in the USA and talk as long as I wanted via the internet. Also, I had Google Talk which gave me a Los Angeles phone#. People would call and leave a message if I wasn't on the internet. The message was then transcribed and sent to me as an email as well as being recorded as a voice message. Using ANY cell phone to call the US is expensive. I did carry a VN Cell Phone and bought vinaphone simm cards so I could TEXT messages to US cell phones and receive messages also. Some other simm cards like Mobiphone didn't work for me. Finally, if you are super cheap like me you will be happy to know that you can buy used cell phones in VN. I bought a very good working Motorola V90 for $15 that had very clear reception and nice big number pad.

Ask the receptionist at yr hotel to buy a cell phone and SIM card for you or you yrself can buy them, very easily, at any street shops.

You can check these service providers:

1. Viettel (run by the army, the signal is stable)
2. Mobifone( always have the promotion when you buy the prepaid simcard)
3. Vinaphone ( same as above, but not often)

Remember to bring a copy of your passport when you want to buy.

Have a good time !

Take your passport with you when you get a pre-paid sim card at the post offices in Vietnam. But at any stree shop you don't need to!
Mobifone is my recommendation with lots of promotion and easy to top-up!
Approximately around 50cent/minute that it costs for a call to the Us!
Enjoy your time in Vietnam!