What is the telephone area code for Orissa state in India?

There are numerous telephone area codes in the state of Orissa (Odisha). You have to specify the city or town. For example, Bhubaneswar is area code 0674, which is +91 674 in international format.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)
There are numerous telephone area codes in the state of Orissa (Odisha). You have to specify the city or town. For example, Bhubaneswar is area code 0674, which is +91 674 in international format.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)