NPO

NPO may refer to:

Medicine

 * Nil per os, Latin for "nothing by mouth", a medical instruction to withhold oral intake of food and fluids
 * neurogenic pulmonary oedema

Science

 * North Pacific Oscillation, a teleconnection pattern in atmospheric conditions over the North Pacific
 * NP optimization problem, an optimization problem that is NP-hard
 * NPO, characterizing thermal stability of a capacitor

Organisations

 * Nonprofit organization
 * National Portfolio Organisation, a UK-based culture and arts organisation receiving substantial funding from Arts Council England
 * National Ports Organisation, former part of the UK Department for Transport
 * National Preservation Office, part of the British Library
 * Scientific Production Association (Nauchno-Proizvodstvennoye Obyedineniye), a form of scientific research-to-production facility in the Soviet Union and the Russian Federation.
 * Nederlandse Publieke Omroep (organization) ("Netherlands Public Broadcasting"), governing body of the Netherlands (Dutch) Public Broadcasting System
 * Nederlands Publieke Omroepbestel ("Dutch public broadcasting system"), the public broadcasting service in the Netherlands
 * Netherlands Pathfinder Organisation (Nederlandse Padvinders Organisatie), one of the organisations that evolved into Scouting Nederland, the national Scouting organisation
 * NPO UK Ltd., a chain of stationery and book shops in Northern Ireland, now part of Eason & Son
 * National Printing Office, one of the three recognized government printers of the Philippines

Other

 * Nanga Pinoh Airport, by IATA code
 * Pochuri language, by ISO 639 code