The official Thai language is widely spoken throughout Thailand, many Thais also speak and understand English, though more so in Bangkok and the major tourist areas. The Thai language itself is challenging to master, but Thai people are happy to help foreigners learn a few words to help them get around.
However, English is typically the common currency for cross-cultural conversation as Thailand hosts visitors from around the world.
Most of the tourist SIM cards sold at airports in Thailand offer “unlimited” data packages. Speeds are typically restricted, either from the beginning or after you’ve used a certain amount of data. A small amount of call credit may or may not be included as well. Other options to buy SIM card are 7 Eleven and official mobile operator shop.
So be sure to buy enough data if you are a heavy user and we would suggest not using a SIM to download a movie — use your hotel or guesthouse WiFi for that.
If you’re buying your SIM through a kiosk or outlet, the staff member will ask for your ID (passport is the standard) as they’ll need this to activate your service. It is not possible to activate a SIM card without ID in Thailand. You can though buy multiple SIMs on one ID without problem.
Prices are broadly similar to the competition, so for the majority of visitors to Thailand, AIS SIM cards are the best option. 3G/HSPA+ is available on the 900 and 2100Mhz bands, while 4G/LTE is provided on 1800 and 2100Mhz (LTE bands 1 and 3.)
True and DTAC’s Happy prepaid services also provided good coverage and speeds in towns and cities. They did have noticeable service gaps in rural areas and on less-populated islands, however.
All providers offer LTE service in 80-90% of the country, including all major cities and towns.
SIM card price is around 500 baht (US$ 15)
Important note:The following assumes that your phone is unlocked. If your phone is locked to a provider in your home country, you’ll need to investigate their roaming plans as a foreign SIM card will not work in your phone.
Thailand's voltage is 220-240AC, 50 Hertz. The plugs in Thailand are not standardised -- there are at least three different types, some two pin and some three, so be sure to either bring a universal adapter or buy one once you arrive in Thailand.
Note that especially in older buildings, the earth pin may not actually be wired in correctly. Make no assumptions with regard to grounding.