NDA is held twice every year. NDA 1 is held during January and NDA 2 is held during September. A Candidate should be between 16.5 to 19.5 years to appear for NDA. In 2020, NDA 1 will be held in the month of April and the applications will be available from January 8th to January 28th. And the application process for September window will begin from the month of June 10th until June 20th. For more information on eligibility criteria, age limit and educational qualification, please visit our page at: https://competition.careers360.com/articles/nda-eligibility-criteria