What is the difference between PAN and TAN?
​​​​​​​​​P​AN stands for Permanent Account Number and TAN stands for Tax Deduction Account Number. TAN is to be obtained by the person responsible to deduct tax, i.e., the deductor. In all the documents relating to TDS and all the correspondence with the Income-tax Department relating to TDS one has to quote his TAN. 
PAN cannot be used for TAN, hence, the deductor has to obtain TAN, even if he holds PAN.
However, in case of TDS on purchase of land and building (as per section 194-​IA) as discussed in previous FAQ, the deductor is not required to obtain TAN and can use PAN for remitting the TDS.​
Further in case of TDS on rent (as per section 194-​IB) TDS on payment of certain sums by Individuals of HUFs (as per section 194M), and TDS on payment made for transfer of virtual digital asset by specified person (as per section 194S), the deductor can use PAN instead of TAN for remitting TDS​