Booking. The private-suite studios run on reservation systems — book ahead, especially evenings and weekends. Jeju is the walk-in exception: 24/7, no reservation, just show up.
What to bring.Swimwear is required for the jjimjilbang's shared pools (non-negotiable); private suites are more relaxed but swimwear is still the norm. Studios typically supply towels.
First plunge. Ease in rather than jumping straight to your limit — most people start with 30–60 seconds. Breathe slowly and steadily, and get out if you feel dizzy or numb beyond comfort. If you're pregnant, have a heart condition, or react badly to cold, check with a clinician first.
Pricing. Atlanta is unusually transparent for plunge pricing — several SweatHouz locations and Jeju publish theirs. Where you see none quoted, assume you'll need to ask the venue directly.