| SIAC | Special Immigration Appeals commission | 特别移民上诉委员会 |
| SIAC | School Improvement Accountability Committee | 学校改善问责委员会 |
| SIAC | Spatial Information and Analysis Consortium | 空间信息与分析联合会 |
| SIAC | Self-Injection Anxiety Counseling | 自我注射焦虑咨询 |
| SIAC | Securities Industries Automation Corporation | 证券工业自动化公司 |
| SIAC | Specialized Information Analysis Center | 专业信息分析中心 |
| SIAC | SocietÀ Italiana Assicurazione Crediti (Italian insurance company) | SocietÀ Italiana Assicurazione Crediti (Italian insurance company) |
| SIAC | SystÈme InformatisÉ d'Aide À la Conduite (French: information system for train engineer in TGV-Trains) | SystÈme InformatisÉ d'Aide À la Conduite (French: information system for train engineer in TGV-Trains) |
| SIAC | Senate Committee on Indian Affairs | 参议院印第安事务委员会 |
| SIAC | Special Immigration Appeals Commission (UK) | 特别移民上诉委员会（英国） |
| SIAC | Sensor Integration and Control | 传感器集成和控制 |
| SIAC | Shape International Angling Club | 形状国际圣公会 |
| SIAC | Southern Intercollegiate Athletic Conference | 南方校际体育大会 |
| SIAC | Submarine Integrated Attack Center | 潜艇综合攻击中心 |
| SIAC | Strike Intelligence Analysis Center | 打击情报分析中心 |
| SIAC | Security Industry Alarm Coalition | 安全行业警报联盟 |
| SIAC | Singapore International Arbitration Centre (Singapore) | 新加坡国际仲裁中心（新加坡） |
| SIAC | SociÉtÉ Internationale des Artistes ChrÉtiens (International Secretariat of Christian Artists) | SociÉtÉ Internationale des Artistes ChrÉtiens (International Secretariat of Christian Artists) |
| SIAC | Staten Island Athletic Club (New York) | 斯塔滕岛体育俱乐部（纽约） |
| SIAC | System Integration And Control | 系统集成和控制 |
| SIAC | Site Improvement Advisory Council | 场地改善咨询委员会 |
| SIAC | School Improvement Advisory Committee | 学校改善咨询委员会 |
| SIAC | Securities Industry Automation Corporation | 证券工业自动化公司 |