AskKaka lists the STD code of Noida that is 0120. Noida is a part of Uttar Pradesh and the ISO code of Uttar Pradesh state is UP.
Noida STD code aka subscriber trunk dialing code is 0120 which is mentioned above on this page of AskKaka. We are great resource of finding Noida std code of Uttar Pradesh (UP).
Useful Info :-
Please take a note that if you are in India and dialing a landline number of Noida then you will have to dial STD code 0120 as a prefix followed by the phone number of a landline user and if you are calling Noida's phone number from a foreign country then you need to add +91 (the country code) followed by 120, e.g. +91120 (no need to add "0" as prefix) followed by the landline phone number.
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