As you know that this TAN is important for all citizens of India. Whatever we can do related to TDS, there is a requirement of TAN. And, this number is used to communicate with all IT companies. Just in case, if somehow, you have not any type of TAN, then there will be a fine of Rs.10000/-. Not only this, but the banks also will not accept any type of TDS return or any payments from the client-side.