Permanent Account Number (PAN) is necessary for a host of transaction, including when you deposit cash at a bank. Cheque deposits may not entail one to write the PAN number, but, for cash deposits it is a must.
If you are depositing an amount in excess of Rs 50,000 in the bank you have to mention the PAN number on the pay-in slip.
Also read How To Apply For Duplicate Pan Card
It's also important to remember that one should mention the PAN number in case of a fixed deposit as well. In case you do not, then the bank will cut tax deducted at source (TDS) at 20 per cent if the amount of interest is in excess of Rs 10,000.
It is important to note that PAN card is needed in case of a host of transactions and hence it is very necessary to obtain one. An individual needs a PAN card when he has to file an income tax return. One cannot file an income tax return without a PAN card. High value transactions like purchase of property and purchase of large sums of jewellery would also need a PAN card.