That is according to a recent tax advisory from SKP. Aadhaar is a unique identification number in India that is obtained by individuals. The government is increasingly using Aadhaar to track the economic activity of individuals and promoting its socio-economic welfare measures. The Finance Act, 2017 has made it mandatory for taxpayers to quote their Aadhaar number or the Enrolment ID of the Aadhaar application form for filing tax returns in India. Taxpayers are also required to link their Aadhaar number to their Permanent Account Number (PAN). These requirements come into effect from 1 July 2017.