| Abbreviation | Definition |
|---|---|
| BNCA | Bhutan Narcotic Control Authority |
| BNCA | Bhutan Narcotics Control Authority |
| BQA | Botswana Qualifications Authority |
| BRA | Brazos River Authority |
| BRA | Brownfield Redevelopment Authority |
| BRAF | Black Sea Broadcasting Regulatory Authorities Forum |
| BRSA | Bradys Run Sanitary Authority |
| BRTA | Bartlesville Redevelopment Trust Authority |
| BRTA | Berkshire Regional Transit Authority |
| BRWA | Broad River Water Authority |
| BSA | Building Service Authority |
| BSA | Business Services Authority |
| BSIA | British Security Industry Authority |
| BTA | Barbados Tourism Authority |
| BTA | Bermuda Tourism Authority |
| BTA | British Tourist Authority |
| BTAO | Bacolod Traffic Authority Office |
| BTMA | Bern Twp Municipal Authority |
| BTPA | Barbados Tourism Product Authority |
| BTPA | British Transport Police Authority British |