| Blessed Sacrament Academy | Academic & Science |
| Bachelor of Science and Arts | Academic & Science |
| Boston Society for Architecture | Academic & Science |
| Board of Scientific Affairs | Academic & Science |
| Belorussian Students Association | Academic & Science |
| Bibliographical Society of America | Academic & Science |
| Botanical Society of America | Academic & Science |
| Boston Society of Architects | Academic & Science |
| Brown Student Agencies | Academic & Science |
| Board of Student Advisers | Academic & Science |
| Fédération des Architectes Suisses | Academic & Science |
| Federazione Architetti Svizzeri | Academic & Science |
| Federation of Swiss Architects | Academic & Science |
| Bund Schweizer Architekten | Academic & Science |
| British Sociological Association | Academic & Science |
| Bulgarian Studies Association | Academic & Science |
| Black Student Association | Academic & Science |
| Borneo Students Association | Academic & Science |
| Bor Students Association | Academic & Science |
| Baylor Student Association | Academic & Science |
| Bendigo Student Association | Academic & Science |
| Bengali Students Association | Academic & Science |
| Balance Sheet Assessment | Accounts and Finance |
| Bossaso | Airport Code |
| Bilateral Swap Arrangements | Banking |
| Bank Secrecy Act | Banking |
| Business Systems Applications | Business |
| Business Systems Analyst | Business |
| Business Solution Architects | Business |
| Broadcast Services Australia Ltd | Business |
| Birmingham Small Arms Company | Business |
| Bilateral Steel Agreement | Business |
| British Small Arms | Business |
| Business Services Associates | Business |
| British Shooting Accessories | Business |
| British Scrap Aluminum | Business |
| Bis(trimethylsilyl)acetamide | Chemistry |
| Building Societies Association | Community |
| British School at Athens | Community |
| Baltimore School for the Arts | Community |
| Boy Scout Advancement | Community |
| Bearing Specialists Association | Community |
| Business Solutions Association | Community |
| Becontree School Association | Community |
| Boy Scouts of America | Community |
| Britney Spears Archive | Community |
| Belfast Safety Axis | Community |
| Baby Sitting Association | Community |
| Bold Stylish Affordable | Community |
| Be Seen Again | Community |
| Binary Source Archive | Computer Assembly Language |
| Branch and Save Address | Computer Assembly Language |
| Bethesda Software Archive | Computing |
| Basic Serving Arrangements | Computing |
| Buy Sell Ads | Computing |
| Bachelor of Science In Agriculture | Educational Degree |
| Bachelor of Science In Accountancy | Educational Degree |
| Bsarc Compressed File Archive | File Type |
| Binding Study Advice | General |
| Basic Stand Alone | General |
| Baby Sitters Anonymous | General |
| Best Sweet and Awesome | General |
| Blind Spot Assistant | General |
| Belted Starter Alternator | General |
| Blind Spot Alert | General |
| Bridgestone South Africa | General |
| Brake System Analysis | General |
| Battery System Assembly | General |
| Bus Safety Act | General |
| Board of Standards and Appeals | General |
| Brewers Supporting Agriculture | General |
| Brewer Supported Agriculture | General |
| Bull Stockwell Allen | General |
| Bethesda Softworks Archive | General |
| Bigoted Scouts of America | General |
| Baby Sitters of America | General |
| Brown Swiss Advantage | General |
| Best Speaker Award (Toastmasters) | General |
| Borovicka Saves All | General |
| Boys Suvs And Academics | General |
| Basic Street Address | General |
| Building Service Authority | Governmental |
| Brigade Support Aria | Governmental |
| Building Services Authority | Governmental |
| Broad Spectrum Antibiotic | Governmental |
| Brain Splattering Art | Governmental |
| Bristol Socialist Alliance | Governmental |
| Bad Suspect Account | Governmental |
| Bad Scope Altogether | Governmental |
| Better Send Assistance | Governmental |
| BHAINSA | Indian Railway Station |
| Business Software Alliance | Information Technology |
| Business Services Authority | Medical |
| Basic Skills Agency | Medical |
| biotin-streptavidin | Medical |
| Bismuth Sulphite Agar | Medical |
| Bowel Sounds Active | Medical |
| Brief Scale for Anxiety | Medical |
| British Society of Audiology | Medical |
| British Stammering Association | Medical |
| Burn Surface Area | Medical |
| Body Surface Area | Medical |
| Bowel Signs Active | Medical |
| Biomolecular Sequence Analysis | Medical |
| Bovine Serum Albumin | Medical |
| Base Support Area | Military and Defence |
| Bosnian Serb Army | Military and Defence |
| Birmingham Small Arms | Military and Defence |
| Brigade Support Area | Military and Defence |
| Brake Slack Adjuster | Military and Defence |
| Beach Support Area | Military and Defence |
| Bosaso, Somalia | Regional |
| The Software Alliance | Softwares |
| Bottom Side Alignment | Space Science |
| Beavercreek Soccer Association | Sports |
| Backpack Somewhere America | Sports |
| Basic Service Area | Telecommunication |