| Date | Day | Commons day type | Commons praying | Lords day type | Lords praying |
|---|---|---|---|---|---|
| Monday | 21st | Prorogation | False | Prorogation | False |
21st September 1857 forms part of the prorogation between the 1st and 2nd sessions of the 17th Parliament, being the 1st prorogation of that Parliament.
Papers laid during this prorogation are reported by both Houses in the 2nd session of the 17th Parliament.