S
- SAARC: South Asian Association for Regional Co-operation
- SAFTA: South Asian Free Trade Area
- SAIL: Steel Authority of India Limited
- SAPTA: SAARC Preferential Trading Agreement
- SARS: Severe Acute Respiratory Syndrome
- SATNAV: Satellite Navigation (Initiative)
- SAVE: SAARC Audio Visual Exchange
- SC: Security Council; Supreme Court; Scheduled Caste
- SCI: Shipping Corporation of India
- SCO: Shanghai Cooperation Organisation
- SCOPE: Standing Conference on Public Enterprises
- SDO: Sub-Divisional Officer
- SDR: Special Drawing Rights (created by the World Bank)
- SEBI: Securities and Exchange Board of India
- SFC: Strategic Forces Command
- SGPC: Shiromani Gurdwara Prabandhak Committee
- SIDBI: Small Industries Development Bank of India
- SIT: Special Investigation Team
- SITE: Satellite Instructional Television Experiment
- SLR: Statutory Liquidity Ratio
- SMS: Short Messaging Service; Subscriber Management System
- SOS: Save Our Souls—distress signal
- SPG: Special Protection Group
- SPIN: Software Process Improvement Networks
- SPV: Solar Photo Voltaic
- SQUID: Super-conducting Quantum Interference Device
- SRE: Space Capsule Recovery Experiment
- SRV: Submarine Rescue Vessel
- SSN: Social Security Number
- STARS: Satellite Tracking and Ranging Station
- START: Strategic Arms Reduction Talks
- STEP: Science and Technology Entrepreneurship Park
- STT: Securities Transaction Tax
- SWAN: State-wide Area Network
- SWIFT: Society for Worldwide Financial Telecommunications
