Tax Deduction Account Number or Tax Collection Account Number is a 10 -digit alpha-numeric number issued by the Income-tax Department. TAN is to be obtained by all persons who are responsible for deducting tax at source (TDS) or who are required to collect tax at source (TCS).
A person deducting tax at source has to file TDS return providing the details of vendors, the amount paid to vendors, amount of tax deducted etc. in the return. After filing of TDS return, TAN holder is required to issue TDS certificate to the person whose tax has been deducted.