As of 2014, there are at least half a dozen telecoms that offer mobile connectivity for tourists. Of these, the three largest are Viettel, Mobifone, and Vinaphone. Viettel may have the widest coverage. Buying at an authorized outlet and registering the sim will save you money and allow you to change texts to English. A passport is required to purchase a SIM card.
Top Prepaid SIM options
Cost: Sims are between 50,000 – 100,000 VND ($2.50 – $5 USD), Top up 10,000 VND ($.47 USD) for 50 mb or 70,000 VND ($3.30 USD) for 600 mb, both lasting one month. Link
Cost: Sims are around 50,000 VND ($2.50 USD) though a Happy Tourist SIM for 250,000 VND ($15 USD) is available that offers 1.5 GB data lasting one month. Or, top up 10,000 VND ($.47 USD) for 50 mb or 70,000 VND ($3.30 USD) for unlimited data , both lasting one month. Happy Tourist SIM and Regular SIM
Cost: Sims are 15,000 VND ($.70 USD), Top up 10,000 VND ($.47 USD) for 50 mb or 70,000 VND ($3.30 USD) for unlimited data , both lasting one month. Link
Where to Buy: Anywhere, but from an authorized center is best.
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