NRR may refer to:
Club Newport Reading Room, a gentlemen's club in Newport, Rhode Island
Electronic mail No Reply Required in the subject field of an email
Law and regulation National Recording Registry in the United States Non-Repudiation of receipt, a legal acknowledgement of origination/authorship of a document (as per internet RFC4130) Office of Nuclear Reactor Regulation in the United States
Medicine/science Net reproduction rate in human fertility Nitrogen reduction reaction, the conversion of N2 to ammonia Noise reduction ratings in hearing protectors
Music National Rock Review, an American website for rock music reviews and interviews
Business
Customer retention#NRR: Net Revenue Retention
Sport Net run rate in cricket
Places IATA code of José Aponte de la Torre Airport in Ceiba, Puerto Rico