new delhi the cbdt has stressed that aadhaarpan linking is mandatory for those filing an income tax return itr and this procedure has to be completed by march 31 this yearconstitutional validity of aadhaar has been upheld by the supreme court of india in september 2018 consequently in terms of section 139aa of income tax act 1961 and order dated june 30 2018 of the central board of direct taxes aadhaarpan linking is mandatory now which has to be completed till march 31 2019 by pan holders requiring filing of itr the cbdt said in an advisory thursdaythe supreme court on february 6 had confirmed that linkage of pan with aadhaar is mandatory for filing of itrsthis reiteration of the september order of the apex court came on an appeal filed by the centre against a delhi high court order allowing two persons to file their itrs for 201819 without linking their aadhaar and pan numbersa bench comprising justices a k sikri and s abdul nazeer said the top court has already decided the matter and upheld the section 139aa of the income tax actthe apex court on september 26 last year had declared the centres flagship aadhaar scheme as constitutionally valid but struck down some of its provisions including its linking with bank accounts mobile phones and school admissionsformer cbdt chairman sushil chandra early this month at an event had said that just 23 crore pan card holders over half of the total pan card holders have so far linked their cards with biometric id aadhaarhe had said the it department has so far issued 42 crore permanent account numbers pan of which 23 crore have been linked with aadhaarchandra said that once aadhaar is linked with pan and pan is linked with bank account the it department can find out spending pattern and other details of the assessee also since many agencies are linked with aadhaar it would be easier to gauge whether the benefits of welfare schemes are availed by eligible persons he saidsection 139 aa 2 of the income tax act says that every person having pan as on july 1 2017 and eligible to obtain aadhaar must intimate his aadhaar number to tax authoritieswhile aadhaar is issued by the unique identification authority of india uidai to a resident of india pan is a 10digit alphanumeric number allotted by the it department to a person firm or entitythe cbdt formulates policy for the tax department