Aadhaar required for National Savings Certificates accounts; enrolment proof acceptable and Aadhaar must be submitted by 31 Dec 2017. Aadhaar is the unique identifier for account holders under the National Savings Certificates (VIII Issue) Rules, 1989; if Aadhaar is not assigned, proof of enrolment may be submitted; depositors who did not provide Aadhaar at application must submit it to the Post Office Savings Bank on or before 31 December 2017.