| Bombing The Atmosphere | Academic & Science |
| Bachelor of Theatre Arts | Academic & Science |
| Boys Town Academy | Academic & Science |
| Business Travel Allowance | Accounts and Finance |
| Bill To Account | Accounts and Finance |
| Bertoua | Airport Code |
| Biota Holdings Ltd | Business |
| Business Transformation Agency | Business |
| Budde Talent Agency | Business |
| Busiiness Transformation Agency | Business |
| Business Technology Architects | Business |
| Business Transaction Activity | Business |
| Best Thieves Association | Business |
| Butylated Hydroxyanisole | Chemistry |
| Bangladesh Tanners Association | Community |
| Travel Allowance | Community |
| Boyz Town Academy | Community |
| Bruce Trail Association (1960 to 2009 -- now BTC) | Community |
| Boxford Trails Association | Community |
| Basic Travel Allowance | Community |
| Boring and Trepaning Association | Community |
| Buckeye Trail Association | Community |
| Bond Traders Association | Community |
| Building Trades Association | Community |
| Burnaby Teachers Association | Community |
| Business Travel Account | Community |
| Burbank Teachers Association | Community |
| Blood Transfusion Association | Community |
| Bear Toad Alliance | Community |
| Boring and Trepanning Association | Community |
| Bedford Teachers Association | Community |
| Basic Trading Area | Computer and Networking |
| Buildings Technology and Academics | Computing |
| Best Time Available | Computing |
| Blue Tooth Analog | Computing |
| Bisdn Terminal Adapter | Computing |
| Broadcasting Technology Association | Computing |
| Best Technology Available | Computing |
| Bitcoin Asset | Cryptocurrency |
| "been To America" | Educational Degree |
| Basic Trading Areas | General |
| Backup Target Appliance | General |
| Booster to AGS | General |
| Back Together Again | General |
| Body Temple Aesthetics | General |
| Backup Target Appliances | General |
| Behind The Axle | General |
| Black Tie Affair | General |
| Bladder Tumour Antigen | General |
| Brain Type Assessment | General |
| Boss Track Attack | General |
| Bell Trucks America | General |
| Bentley Team Absolute | General |
| Bengal Taxi Association | General |
| Blouberg Taxi Association | General |
| Bermuda Taxi Association | General |
| Be Truck Aware | General |
| Bumper Test Area | General |
| Boyce Thompson Arboretum | General |
| Bladder Tumour Associated | General |
| Batteries Tires and Accessories | General |
| Behavioral Threat Assessment | General |
| Between Tenants Agreement | General |
| Brunswick Transit Alternative | General |
| Basic Transport Allowance | General |
| Bio To Adopt | General |
| Better Than Average | General |
| Block Token Authenticator | General |
| Budget Turnaround | General |
| Blacks To Apear | General |
| Bus Ticketing Application | General |
| Bullock Tice Associates | General |
| Building The Ambition | General |
| Blue Tide Aquatics | General |
| Bubble Tip Anemone | General |
| Bus Ticketing Applicationmore | General |
| Bulgaria Travel Agent | General |
| The Booster To Ags | General |
| Beat the Average | General |
| Botulinum Toxin A A | General |
| Berkeley Training Associates | General |
| Bad Trader Alerts | General |
| Building Trades | General |
| Bow Tie Antenna | General |
| BioTerroism Act of 2002 | Governmental |
| Bicycle Transportation Account | Governmental |
| Border Trade Alliance | Governmental |
| Bermuda Tourism Authority | Governmental |
| Barbados Tourism Authority | Governmental |
| Bicycle Transportation Alliance | Governmental |
| British Tourism Agency | Governmental |
| Board of Tax Appeals | Income Tax |
| BIHTA | Indian Railway Station |
| B*tch Team Alpha | Internet |
| bladder tumour antigen (BTA) | Medical |
| Blood and Transplant Authority, formally, the NHS Blood and Transplant Authority | Medical |
| botulinum toxin A | Medical |
| British Thyroid Association | Medical |
| Brain Transplant Argument | Medical |
| Biological Terrain Assessment | Medical |
| Bladder Tumor Associated | Medical |
| Bladder Tumor Antigen | Medical |
| But Then Again | Messaging |
| Business Travel and Accident Insurance | Messaging |
| Best Technical Approach | Military and Defence |
| British Tourist Authority | Regional |
| Building Technology Associates | Technology |
| Business Technology Association | Technology |
| Business Technology Associates | Technology |