AskKaka lists the STD code of Nicobar Island that is 03193. Nicobar Island is a part of Andaman and Nicobar Islands and the ISO code of Andaman and Nicobar Islands state is AN.
Nicobar Island STD code aka subscriber trunk dialing code is 03193 which is mentioned above on this page of AskKaka. We are great resource of finding Nicobar Island std code of Andaman and Nicobar Islands (AN).
Useful Info :-
Please take a note that if you are in India and dialing a landline number of Nicobar Island then you will have to dial STD code 03193 as a prefix followed by the phone number of a landline user and if you are calling Nicobar Island's phone number from a foreign country then you need to add +91 (the country code) followed by 3193, e.g. +913193 (no need to add "0" as prefix) followed by the landline phone number.
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