A convenient way of getting Thai Prepaid SIM card is to order one from Amazon. In July 2019 , it was just 499 for 3 GB data and 100 mins of local calls .Plus they provide considerable talk time to India as well by just using a prefix before dialing Indian numbers. Activation is automatic as the phone works as soon as you touch the ground. Your validity starts from when you land.
Apart from normal benefits , a Thai SIM card allows one to book Grab Taxi (Uber like) which is great for tourists .
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