AskKaka lists the STD code of Coimbatore that is 0422. Coimbatore is a part of Tamil Nadu and the ISO code of Tamil Nadu state is TN.
Coimbatore STD code aka subscriber trunk dialing code is 0422 which is mentioned above on this page of AskKaka. We are great resource of finding Coimbatore std code of Tamil Nadu (TN).
Useful Info :-
Please take a note that if you are in India and dialing a landline number of Coimbatore then you will have to dial STD code 0422 as a prefix followed by the phone number of a landline user and if you are calling Coimbatore's phone number from a foreign country then you need to add +91 (the country code) followed by 422, e.g. +91422 (no need to add "0" as prefix) followed by the landline phone number.
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