Yes, Miette, Radium and Banff Upper Hot Springs accommodate large groups. Reservations and pre-bookings are not available. If the facility is at capacity upon arrival, large groups will need to wait in line whether they have a pre-paid voucher or not.
Larger groups may need to stagger their entry to minimize wait times.
A group discount is available when 10 or more people pay in a single transaction. Private pool rentals are not available.