NTI may refer to:

• Nti (surname)

• Network Telephone Interface, alternative term for the network interface device
• NTi Audio, company
• National Telecommuting Institute, non-profit organization dedicated to work-at-home opportunities for primarily the disabled
• New Technology Institute, training venue in the Eastside of Birmingham, England
• Nociceptive trigeminal inhibition tension suppression system, dental mouthguard
• Northwest Territorial Imperative, North American separatist movement
• Nuclear Threat Initiative, non-profit organization working to prevent catastrophic attacks and accidents with weapons of mass destruction
• Nunavut Tunngavik Incorporated, legal representative of the Inuit of Nunavut
• Vector NTI, software package
• NTI, the IATA code for Steenkool Airport, Indonesia