The Frontier Airlines Crew Room at MDW is located outside of security on the ticket counter level. You will need to head to the hallway located between the Allegiant and Delta ticket counters' upper level. Once there, you will need to go through the doorway located just before the men's restroom on the right side. The Frontier Airlines Crew Room will be on the right side. The current door code is 2018.
As a reminder, residing or the appearance of living in the crew room/sleep room overnight or for extended periods of time is not permitted.