The Unique Identification Authority of India (UIDAI) is a statutory authority established under the provisions of the Aadhaar (Targeted Delivery of Financial and Other Subsidies, Benefits and Services) Act, 2016 (“Aadhaar Act 2016”) on 12 July 2016 by the Government of India, under the Ministry of Electronics and Information Technology (MeitY). The Aadhaar Act 2016 has been amended by the Aadhaar and Other Laws (Amendment) Act, 2019 (14 of 2019) w.e.f. 25.07.2019.

UIDAI was created to issue Unique Identification numbers (UID), named as "Aadhaar", to all residents of India. The UID had to be (a) robust enough to eliminate duplicate and fake identities, and (b) verifiable and authenticable in an easy, cost-effective way. As on 31 March 21, the Authority has issued 128.99 crore Aadhaar numbers to the residents of India.

Under the Aadhaar Act 2016, UIDAI is responsible for Aadhaar enrolment and authentication, including operation and management of all stages of Aadhaar life cycle, developing the policy, procedure, and system for issuing Aadhaar numbers to individuals and perform authentication and the security of identity information and authentication records of individuals.