Ultra Low Cost Airlines: Are Spirit, Frontier, and Allegiant Worth It? (2026)

# Ultra Low Cost Airlines: Are Spirit, Frontier, and Allegiant Worth It? (2026)

Ultra low cost carriers (ULCCs) can offer the cheapest base fares in the US — sometimes $19–$49 each way. But fees for carry-on bags, checked bags, seat selection, and snacks mean the final price is often comparable to, or more than, a mainstream carrier. Whether they're worth it depends on how you travel.

Here's a complete comparison of Spirit, Frontier, and Allegiant — and how they stack up against Southwest and the major carriers.

What Is an Ultra Low Cost Carrier?#

ULCCs separate the base airfare from every additional service, charging fees for:

• Carry-on bags (overhead bin access)
• Checked bags
• Seat selection
• Priority boarding
• Food and drinks
• Printing your boarding pass at the airport

The strategy: advertise the lowest possible base fare, then recoup revenue through ancillary fees. Many travelers pay more in fees than they did for the ticket.

Spirit vs Frontier vs Allegiant: The Key Differences#

Bag Fees: The Number That Actually Matters#

Bag fees are where ULCCs get you. Here are current fees for the most common scenario — a carry-on bag:

Spirit Airlines Carry-On Fee (2026)#

• Personal item (fits under the seat, max 18"×14"×8"): Free
• Carry-on bag (overhead bin): $39–$79 depending on route and when you add it

- Cheapest at booking online

- Most expensive at the gate ($79+)

• If your bag doesn't fit the personal item dimensions at the gate: you pay the carry-on fee right there

Spirit's rule: Only one personal item free. Every overhead bin bag costs extra. Many travelers are caught off guard at the gate when a small backpack is deemed too large.

Frontier Airlines Bag Fees (2026)#

• Personal item (under seat, max 14"×18"×8"): Free
• Carry-on bag (overhead bin): $35–$75

- Buy at booking for lowest price; jumps to $55–$75 within 24 hours of flight

• 1st checked bag (50 lbs): $35–$79
• 2nd checked bag: $55–$99

Frontier's "WORKS" bundle: $89–$180/round-trip includes carry-on, checked bag, seat selection, and no change fee. For travelers who need these, WORKS often makes Frontier price-competitive with traditional carriers.

Allegiant Air Bag Fees (2026)#

• Personal item: Free
• Carry-on bag: $18–$50
• 1st checked bag: $18–$50
• Allegiant's fees are notably lower than Spirit and Frontier

Allegiant flies to and from smaller regional airports (Bellingham instead of Seattle; Punta Gorda instead of Fort Myers), which can save $20–$40 each way in Uber/parking costs — or cost you if those airports are inconvenient.

How Much Does It Really Cost to Fly Spirit?#

Let's price out a round-trip from Chicago to Miami for one person, carrying a standard carry-on:

Spirit Airlines (Base):

• Base fare: $59 each way = $118 round-trip
• Carry-on bag: $49 each way = $98 round-trip
• Seat selection (window): $25 each way = $50 round-trip
• Total: ~$266

Southwest Airlines (same route, with a free carry-on and checked bag):

• Base fare: $149 each way = $298 round-trip
• Bags: $0 (first 2 checked bags free)
• Seat selection: $0 (open seating, no extra charge)
• Total: ~$298

With bag fees and seat selection, Spirit's advantage shrinks to $32 for a worse experience (no assigned seats, higher cancellation rate). Travelers who check bags frequently may find Spirit more expensive than Southwest.

When Ultra Low Cost Airlines Are Actually Worth It#

ULCCs make financial sense when:

1. You're traveling with just a personal item — fits under the seat, no overhead bin needed. One backpack or small bag for a weekend trip with no checked luggage.
2. You don't care about seat assignment — willing to take whatever seat remains, or sitting separately from your travel partner.
3. Prices are dramatically lower — if Spirit is $99 and United is $350 for the same route, even with a $45 carry-on fee, Spirit wins.
4. You're flying a route ULCCs specialize in — domestic leisure routes where legacy carriers price high.
5. You're using the Frontier GoWild pass — unlimited flights for ~$300/year; extraordinary value for flexible frequent flyers.

When to Avoid Ultra Low Cost Airlines#

Skip ULCCs when:

1. You have checked bags — fees can add $80–$160 round-trip, eliminating the savings.
2. Your schedule is tight — ULCCs have higher cancellation and delay rates. A missed connection on Spirit/Frontier on a Sunday afternoon can mean a 24+ hour delay.
3. You're traveling with family — seat selection fees per person add up fast. A family of four paying $20/seat each way = $160 in seat fees alone.
4. You need to change your ticket — Basic Economy on ULCCs typically offers no changes or changes at high cost.
5. The airport is inconvenient — Allegiant flies to secondary airports; add transportation cost to your total.

Frontier GoWild Pass: The Best ULCC Value#

Frontier's GoWild All-You-Can-Fly pass at ~$299/year allows unlimited domestic flights on standby. For flexible travelers (remote workers, students, retirees) who can take early morning flights with low load factors, this is genuinely extraordinary value — potentially hundreds of flights per year for $300.

The catch: you don't know if you'll get on the flight until the day of (or same morning). Not for travelers with firm schedules.

FAQ#

Are ultra low cost airlines safe?

Yes — Spirit, Frontier, and Allegiant are all FAA-certified and maintain the same safety standards as all US airlines. Safety is not where they cut corners. The difference is customer service, reliability, and ancillary fees.

What is Spirit's cancellation policy?

Spirit charges a change/cancellation fee of $49–$99 depending on how far in advance you cancel. Within 24 hours of booking, you can cancel for free (DOT rule). Spirit's "Flight Flex" add-on allows one free modification.

Is Frontier better than Spirit?

Both are ULCCs with similar pricing. Frontier's WORKS bundle is a better deal than Spirit's equivalent if you need bags and seats. Allegiant has lower base fees but serves fewer routes. All three have higher cancellation rates than major carriers.

Does Southwest charge for bags?

Southwest has historically included two free checked bags and a carry-on — a major differentiator. As of 2024, Southwest announced changes to bag policies; check their current policy at southwest.com before booking.

How do I avoid bag fees on Spirit and Frontier?

1. Travel with only a personal item (small backpack under 18"x14"x8")
2. Buy bags at initial booking (cheapest price)
3. Use Frontier's WORKS bundle if you need bags + seat selection
4. Consider a Spirit credit card (includes free carry-on)

Bottom Line#

Ultra low cost airlines offer the lowest base fares in the US but charge for everything else. For carry-on-only travelers on non-time-sensitive routes, they can represent genuine savings. For travelers with checked bags, families who need seat assignments, or anyone with a tight schedule, the total cost after fees often equals or exceeds a mainstream carrier — with worse reliability.

Compare prices for your specific route including estimated fees before booking.

Related Comparisons#

• Spirit Airlines vs Frontier: Full Comparison
• Southwest vs Spirit Airlines: Which Is Cheaper?
• American Airlines vs Delta: Which Is Better?