According to the August 30 notification by the CBDT, the apex policymaking body for the Income Tax Department, a person not having a PAN who furnishes Aadhaar for filing an income tax return "shall be deemed" to have applied for allotment of PAN. Such persons will not be required to apply for a PAN or submit any more documents, according to the CBDT. (Also read: Aadhaar, PAN steps to expand tax base, say experts)

The rule has come into effect from September 1, according to the CBDT.

The tax department will "obtain demographic information of an individual from the Unique Identification Authority of India (UIDAI)" for allotment of Permanent Account Number (PAN), the notification added. (Also read: Taxman to "suo motu" allot PAN to those only furnishing Aadhaar)

In her Budget speech on July 5, Finance Minister Nirmala Sitharaman had announced that PAN and Aadhaar would be made "interchangeable" as the government would allow those not having a PAN to file I-T returns by simply quoting their Aadhaar number, and also use it wherever they are required to quote PAN.

Aadhaar holds details such as name, date of birth, gender, photo, address and biometrics of individuals. (Also read: "Either Aadhaar or PAN will do")

A PAN is a 10-digit alphanumeric number allotted by the Income Tax Department to entities such as persons and firms.

Over 120 crore Aadhaar numbers have been issued in the country and about 41 crore PANs generated. (Also read: Aadhaar can be used for cash transactions above Rs. 50,000, says government)

Out of these, more than 22 crore PANs are linked with Aadhaar.

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