NPD
- NPD (petrol)
- NPD Group
- Narcissistic personality disorder
- National Democratic Party of Germany
- National Democratic Party of Germany (2023)
- National Party of Germany
- Nawapara Road railway station
- New Democratic Party of Canada
- New Palangdharma Party
- New Party Daichi
- New Pudsey railway station
- New product development
- Newark Police Department (New Jersey)
- Nitrogen–phosphorus detector
- Non-parental ditype
- Nuclear Power Demonstration
- Nuclear Protein Database