MSN is a web portal provided by Microsoft.

MSN may also refer to:

• MSN Dial-up, the Internet service provider (originally The Microsoft Network)
• Windows Live Messenger, once synonymous with 'MSN' in Internet slang
• List of services by MSN, a list that includes several services Microsoft has rebranded

• Dane County Regional Airport (IATA airport code MSN) in Madison, Wisconsin
• Manufacturer's serial number, a unique identifier assigned by some manufacturers. The abbreviation is typically used by aircraft companies.
• Master of Science in Nursing
• Maquila Solidarity Network
• Medium spiny neuron
• Meeker Southern Railroad, which uses the reporting mark 'MSN'
• Meter serial number
• Mountaineer Sports Network, a former business identity of the West Virginia Radio Corporation
• Lionel Messi, Luis Suárez and Neymar, dubbed "MSN", the main attacking trident of Spanish football club FC Barcelona from 2014 to 2017
• MSN, the human gene which produces the moesin protein
• The National Sports Council of Malaysia, Majlis Sukan Negara Malaysia

• MSM (disambiguation)