The check-in process for What Terminal is Spirit Airlines at LAS is generally efficient. The airline provides plenty of self-service kiosks, which makes it easy for passengers who have already checked in online to quickly print their boarding passes or baggage tags. The staff at the baggage drop counters are helpful and keep the lines moving smoothly, even during busy times. However, during peak hours, the area can get crowded, so arriving a bit earlier is advisable.