Individuals not having a PAN will be able to quote Aadhaar instead while filing their income tax returns, as announced in the Budget. (Also read: "Either Aadhaar or PAN will do")

The government has said that Aadhaar will be accepted interchangeably with PAN under the Income Tax Act. (Also read: Taxman to "suo motu" allot PAN to those only furnishing Aadhaar)

Tax experts believe this will lead to expansion of the tax base. (Also read: Aadhaar, PAN steps to expand tax base, say experts)

This means Aadhaar - or the 12-digit Unique Identity Number or UID - can also be quoted for cash transactions of more than Rs. 50,000.

Similarly, Aadhaar can also be quoted for deposit or withdrawal of more than Rs. 50,000 worth of cash from a bank account in place of PAN.

Currently, quoting of PAN is mandatory for cash transactions - such as hotel or foreign travel bills - exceeding Rs. 50,000.

PAN is also mandatory on purchase of immovable property of over Rs. 10 lakh.

“PAN and Aadhaar both will exist because some people may prefer to use Aadhaar, some people may prefer to use PAN. But at the back end, for every PAN there will be an Aadhaar," Revenue Secretary Ajay Bhushan Pandey said last week. (Also read: Aadhaar can be used for cash transactions above Rs 50,000, says government)

In the first Budget after its return to power in May this year, the government also proposed to consider issuing Aadhar card to NRIs with Indian passports on arrival in the country without waiting for the mandatory 180 days. (Also read: Aadhaar for NRIs on arrival without waiting, says government)