The provisions of Section 203A of the Income Tax Act, 1961 require all persons who deduct or collect tax at source to apply for the allotment of TAN. The section also makes it mandatory to quote TAN in all TDS / TCS / Annual Information Returns, payment challans and certificates to be issued. Deductor cannot file TDS / TCS statements and deposit challans for TDS / TCS payments in banks without TAN. Failure to apply for TAN or not quoting the same in the specified documents attracts a penalty of ` 10,000/-.