| B12 | B12 | SST/Serum | 24 hours |
| Beta HCG | BHCG | SST/Serum | 48 hours |
| Bicarbonate | BIC | SST/Serum | 48 hours |
| Bilirubin (total) | BILI | SST/Serum | 48 hours |
| Blood Film Examinations | FILM | EDTA | 48 hours |
| Blood Group | ABO | EDTA | 48 hours |
| BNP (NT-pro-BNP) | BNP | SST/Serum | 48 hours |
| BUN (Blood Urea Nitrogen) | UR | SST/Serum | 48 hours |