| Order / Lane | Bib | ATHLETE | COUNTRY | PB | SB 2015 | 
|---|---|---|---|---|---|
| 2 | 513 | Novlene Williams-Mills |  JAM | 49.63 | 50.47 | 
| 3 | 881 | Phyllis FRANCIS |  USA | 50.46i | 50.50 | 
| 4 | 512 | Shericka JACKSON |  JAM | 50.03 | 50.03 | 
| 5 | 142 | Shaunae MILLER-UIBO |  BAH | 49.92 | 49.92 | 
| 6 | 879 | Allyson FELIX |  USA | 49.59 | 49.89 | 
| 7 | 390 | Christine Ohuruogu |  GBR | 49.41 | 50.16 | 
| 8 | 509 | Christine Day |  JAM | 50.16 | 50.16 | 
| 9 | 515 | Stephenie Ann MCPHERSON |  JAM | 49.92 | 50.32 |