CME Group’s Micro E-mini futures contracts expire on a quarterly basis, settling to the official opening level of their respective index on the third Friday of March, June, September and December.
Each calendar month expiration is identified by a single letter as follows:
Expiration (Last Trading Day): Third Friday of the contract month
January – F
February - G
March -H
April -J
May - K
June - M
July - N
August - Q
September -U
October - V
November -X
December -Z