Spirit’s fare calendar highlights the lowest base fares, which is extremely helpful for spotting cheap travel dates quickly. However, those prices only reflect the cost of the seat itself. Once you start adding extras, the “best deal” can change.
Why the Lowest Fare Isn’t Always the Cheapest Trip
Spirit operates on an ultra-low-cost model. That means:

• Carry-on and checked bags cost extra
• Seat selection is optional but paid
• Changes or cancellations usually involve fees

If you’re traveling with luggage, want a specific seat, or need flexibility, the final price may rise enough that another airline looks more competitive.
When the Lowest Calendar Fare Is a Great Deal
The cheapest dates on Spirit’s calendar work best if:

• You’re packing light (personal item only)
• Your travel plans are firm
• You’re flying short-haul
• You don’t need premium seating or add-ons

In these cases, the calendar fare can be genuinely hard to beat.
How to Decide if It’s Worth It
Before booking, compare:

• Total cost after bags and seats
• Change and cancellation rules
• Flight times and connections

The calendar is an excellent starting point, but the smartest deal comes from evaluating the full price—not just the headline fare.
Bottom line: Spirit’s lowest calendar fares are powerful for saving money, but the “best deal” depends on how you travel, not just how much the ticket costs upfront.