Frontier vs Spirit vs Southwest for US Domestic Budget Travel in 2026: What Changed and Who Wins Now

The US budget-airline map redrew itself in 2026. Spirit ceased operations on May 2. Southwest ended the 54-year "Bags Fly Free" era and launched assigned seating. Frontier stayed lean, doubled down on the GoWild Pass, and became the last national ultra-low-cost carrier still flying. This guide walks how the three names travelers still search for compare now, so you can pick the right budget airline for the trip you are actually booking in the second half of 2026.

The verdict

If you are booking a US domestic trip in the second half of 2026, only two of the three are a live choice, and the fit depends more on how you pack than on the sticker fare.

Frontier Airlines is the last national ultra-low-cost carrier in 2026, and it usually posts the lowest base fare on trunk domestic routes when you strip the extras. Frontier charges roughly $60 to $99 for a carry-on that goes overhead, per Frontier's Optional Services page, and the fee stair-steps up the closer to departure you add it. A personal item that fits under the seat in front stays free.

The GoWild Pass at $199 for the 2026 Summer version (valid for purchase through August 31, 2026, travel through January 4, 2027) unlocks unlimited seats on select routes when Frontier releases day-before inventory. Book flights via ShopBack partners on the hotel and car legs of the trip to earn cashback on the parts of the itinerary that live outside the airline. Verify the current bag fee with the Bag Price Checker at flyfrontier.com before you commit.

Spirit Airlines is no longer a choice. Spirit wound down all operations on May 2, 2026 after its second Chapter 11 restructuring failed, making it the first major US airline in roughly 25 years to shut down for financial reasons, per CNN and NPR reporting. Some former Spirit routes were absorbed by Frontier, Breeze, JetBlue, and Southwest within weeks; Hopper data cited by NPR reported an average 11 percent fare bump on those routes shortly after the shutdown. If you are holding a future Spirit ticket, work the refund through your card issuer or DOT rules first, then rebook on a live carrier. Compare hotels via ShopBack Travel Planner before booking the replacement trip so the hotel-and-car spend still earns.

Southwest Airlines is the strongest pick for families, flexible planners, and A-List Preferred elites or Rapid Rewards cardholders in 2026. Southwest ended Bags Fly Free on May 28, 2025 and raised checked-bag fees on April 9, 2026 to $45 first bag and $55 second bag on most fares, per Upgraded Points and CBS News. Two free checked bags still ride along with A-List Preferred, Choice Extra, active-duty military, and qualifying Rapid Rewards credit cards.

Assigned seating launched on January 27, 2026, ending open boarding after 54 years; Basic fares are auto-assigned at check-in, and Choice and above unlock seat selection. Southwest remains the only major US airline with no change or cancel fees on most fares, which often flips the total-cost math versus Frontier for any trip whose dates might slip. Start at shopback.com/travel to see cashback offers alongside your hotel and car booking for the Southwest trip.

Household math: for a solo traveler packing in a personal item on flexible dates, Frontier or the GoWild Pass wins on absolute cost. For a family of four on a fixed school-break week, Southwest usually wins on total trip cost once bags, change risk, and Rapid Rewards points are counted. Spirit fills neither slot in 2026.

💡 Plan your US trip on ShopBack Travel Compare hotels via ShopBack Travel Planner before booking to earn cashback on the hotel-and-car legs of the itinerary.

Route trip planning through ShopBack: ShopBack Travel · Booking.com on ShopBack · Hotels.com on ShopBack · Expedia on ShopBack

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What happened to the US budget-airline map in 2026

Three concurrent shifts reshaped US domestic budget travel over the first half of 2026.

The first was Spirit's collapse. Spirit filed its second Chapter 11 on August 29, 2025, five months after emerging from its first restructuring in March 2025. The airline filed a restructuring support agreement in March 2026 that would have shrunk the fleet to 76 to 80 aircraft by Q3 2026 with total debt and lease obligations of roughly $2 billion.

That plan did not survive the spring. AerCap terminated aircraft leases, credit card processor Elavon drained liquidity, and a sharp jet-fuel spike tied to the 2026 Iran conflict pushed unit costs above what the ULCC pricing model could bear. Bailout negotiations with the second Trump administration failed. Spirit ceased operations on May 2, 2026 in a court-supervised wind-down and asset liquidation.

The second was Southwest's business-model reset. Southwest ended Bags Fly Free on May 28, 2025 for flights booked after that date, introduced a first checked-bag fee of $35, and pushed it to $45 on April 9, 2026 alongside a $55 second-bag fee, citing the same jet-fuel spike that broke Spirit.

Assigned seating went live for flights on and after January 27, 2026, ending open seating after 54 years. A new Basic fare (formerly Wanna Get Away) removed complimentary seat selection; Choice and Choice Extra tiers reshaped the mid- and premium-fare deck. Southwest kept its structural advantages (two free bags for elites and cardholders, no change fees on most fares, dense mid-continent network), but the airline no longer sits at the ULCC price point on a bag-inclusive comparison.

The third was Frontier's consolidation as the last national ULCC. Frontier held on through a rough 2025 (nine-month loss of $190 million and a leadership change from Barry Biffle to James Dempsey), then repositioned around the GoWild Pass, add-on bundles like The Works, and route pickups from former Spirit markets. Merger talks with Spirit resurfaced in late 2025 but did not produce a deal before Spirit's wind-down.

The layered effect: US budget travelers now choose between one ULCC (Frontier) with hard-nosed bag economics, one full-service budget airline (Southwest) with more expensive bags but generous change policy, and a growing bench of secondary options (Breeze, Allegiant, JetBlue Basic Blue) that filled specific Spirit routes. The three-way "Frontier vs Spirit vs Southwest" frame most travelers still search for is a 2024 question with a 2026 answer.

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Frontier Airlines: the last national ULCC

Frontier is the default 2026 pick for solo travelers who pack light, are flexible on dates, and want the lowest possible base fare on domestic trips.

The core model. Frontier is an ultra-low-cost carrier that unbundles nearly every extra: seat selection, carry-on that goes overhead, checked bags, snacks, and priority boarding are all priced separately from the base fare. A personal item that fits under the seat stays free, which is the single most important lever for keeping Frontier's price advantage intact. Frontier's route network runs point-to-point from a Denver hub, with a wide but thinner map than Southwest's; many markets are served two to four days a week rather than daily.

The GoWild Pass in 2026. Frontier's flagship 2026 product is the GoWild All You Can Fly Pass. The Summer 2026 version launched at $199, is available for purchase through August 31, 2026, and covers travel through January 4, 2027, per Forbes Advisor. The pass unlocks unlimited domestic and select international flights on Frontier when the airline releases day-before inventory; pass holders still pay taxes, fees, and any add-on bag or seat fee on each flight, but the base fare goes to zero on eligible seats. GoWild is a strong fit for solo, flexible, personal-item-only travelers who can fly midweek and treat blackout dates around Thanksgiving, Christmas, and spring break as non-events.

Bag economics. Frontier's carry-on stored overhead runs about $60 to $99 in 2026, checked bags run a similar range depending on route and timing. A checked bag is often cheaper than a carry-on in Frontier's fee grid, which is the opposite of most carriers and a quirk worth checking before you pack. Confirm current pricing at flyfrontier.com/optional-services before you commit; Frontier updates the fee grid frequently.

Where Frontier wins. Solo travelers on flexible dates; personal-item-only packers on 1- to 3-night trips; leisure travelers with no elite status on any legacy carrier; anyone building a domestic itinerary that starts or ends in Denver, where Frontier's hub gives the deepest schedule.

Where Frontier struggles. Families of four (per-person bag fees compound fast); travelers on fixed date windows with no flex; anyone needing overhead carry-on space; markets served fewer than four days a week where the connection risk breaks the trip.

How ShopBack fits. Frontier itself is not typically a ShopBack cashback partner in the US, so the ShopBack angle sits on the hotel and car portion of the trip. Compare hotels via ShopBack Travel Planner before booking to layer cashback across supported OTA and hotel partners for the nights the traveler is on the ground. Start at shopback.com/travel to see live cashback offers alongside the flight itinerary. For pre-trip retail (luggage, packing cubes, sunscreen, chargers), activate cashback via ShopBack before checkout at supported partners.

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Spirit Airlines: what to know now that Spirit is gone

Spirit is included in this comparison because travelers still search "Frontier vs Spirit vs Southwest" out of habit, but the honest 2026 answer is that Spirit is no longer an option.

The 2026 shutdown, briefly. Spirit filed a first Chapter 11 in November 2024, emerged in March 2025, filed a second Chapter 11 in August 2025, and wound down operations on May 2, 2026. The second bankruptcy failed because rising jet-fuel costs tied to the 2026 Iran conflict made the ULCC unit-cost model unsustainable at Spirit's fleet size, per Fortune reporting from April 2026, and because AerCap terminated aircraft leases while Elavon drained liquidity. Bailout negotiations with the federal government failed. Spirit was the first major US airline in roughly 25 years to shut down for financial reasons, per NPR.

If you are holding a future Spirit ticket. File the refund with your credit card issuer first (Section 605 chargeback rights) and simultaneously through DOT protections for cancelled flights. Do not wait for Spirit's court-supervised wind-down to reach ticketed passengers; the card-issuer path is faster and cleaner in most cases. Once the refund is in motion, rebook on a live carrier for the same trip.

Where former Spirit routes went. Frontier picked up a share of Spirit's Fort Lauderdale, Orlando, and Denver point-to-point routes. Breeze Airways moved into a chunk of Spirit's secondary-airport network (Charleston SC, Providence, Provo). JetBlue extended some Northeast to Florida coverage. Southwest absorbed several Vegas and Phoenix pairs. Hopper data cited in press coverage showed an average 11 percent fare increase on former Spirit routes within weeks of the shutdown, which is the honest baseline for what "the loss of Spirit" cost the median leisure traveler.

What the Spirit gap means for your 2026 booking. If your baseline was "cheapest Spirit fare, personal item only, don't care about seat," Frontier is the closest structural substitute. If your baseline was "Big 3 airport (Fort Lauderdale, Orlando, Vegas) to a Northeast city on a fixed weekend," Southwest and JetBlue are now the more reliable picks. If your baseline was a secondary airport (Provo, Akron, Charleston SC), Breeze Airways is the most direct replacement.

How ShopBack fits. Compare hotels via ShopBack Travel Planner before booking the replacement trip. Even where the flight is now 10 to 15 percent pricier post-Spirit, the hotel-and-car portion still earns cashback via ShopBack partners such as Booking.com, Hotels.com, Expedia, and Priceline. Start at shopback.com/travel to line up the replacement itinerary.

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Southwest Airlines: the full-service budget pick after Bags Fly Free

Southwest is the strongest 2026 pick for families, flexible planners, and travelers with Rapid Rewards status or a Southwest credit card.

The core model in 2026. Southwest is now a full-service budget airline rather than a bag-inclusive ULCC alternative. First checked bag runs $45, second bag $55 as of April 9, 2026, per Upgraded Points and CBS News. Two free checked bags remain the norm for A-List Preferred elites, Choice Extra fare passengers, active-duty military, and qualifying Rapid Rewards credit cardholders. Carry-on and one personal item at typical size limits are still free. Southwest operates the deepest mid-continent domestic network of any budget-tier US airline, with over 100 destinations and strong nonstop density from Denver, Nashville, Chicago Midway, Baltimore, and Dallas Love Field.

Assigned seating, since January 27, 2026. Southwest ended 54 years of open seating on January 27, 2026, per CNBC and ABC News. The Basic fare (formerly Wanna Get Away) no longer includes complimentary seat selection; passengers are assigned seats at check-in. Choice, Choice Preferred, and Choice Extra unlock seat selection at booking, extra legroom seats debuted on the same day, and boarding order is driven by seat location, elite status, and fare bundle. The refined process was tuned again in February 2026 after early-rollout backlash. Families with kids under 13 are auto-seated together where possible; when the algorithm cannot, Southwest offers rebooking to the next available flight.

The change-and-cancel advantage. Southwest remains the only major US airline with no change or cancel fees on most fares in 2026. Basic fare changes cost the fare difference but no separate change fee; Choice and above allow same-day changes at no cost. For any trip where the schedule might slip (family emergencies, work travel, weather-prone winter itineraries), this alone often flips Southwest's higher headline fare into the cheapest total-cost option versus Frontier.

Where Southwest wins. Families of four (two elites or Rapid Rewards cardholders can keep bags free); flexible planners who need change-fee-free rebooking; travelers earning or redeeming Rapid Rewards (a 25,000 to 40,000 point one-way to Hawaii still holds); trips through the mid-continent hubs where Southwest's nonstop density beats every competitor.

Where Southwest is not the pick. Solo travelers who fit everything in a personal item and would rather pocket the $60 to $80 savings vs Frontier; travelers who insist on legacy-carrier cabin experience (Delta, United, American); anyone whose home airport is not on Southwest's network.

How ShopBack fits. Southwest itself is not typically a ShopBack cashback partner in the US, so the ShopBack layer applies to the hotel and car components of the trip. Start at shopback.com/travel to see cashback on Booking.com, Hotels.com, Expedia, and Priceline for the destination city. For Southwest credit card sign-ups, applying through a cashback route (where the issuer is a partner) can add a one-time rebate on top of the Rapid Rewards sign-up bonus; verify current offers on shopback.com before applying.

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Route your US trip through ShopBack Travel Planner: ShopBack Travel · Booking.com · Hotels.com · Priceline

The three side by side (2026)

Dimension	Frontier Airlines	Spirit Airlines	Southwest Airlines
Status (Aug 2026)	Operating, last national ULCC	Wound down May 2, 2026	Operating, full-service budget
Base-fare model	Ultra-low-cost, unbundled	Formerly ULCC	Full-service budget (post Bags Fly Free)
Carry-on overhead	About $60 to $99	Not applicable	Free at standard size
Personal item	Free	Not applicable	Free
First checked bag	Route-priced, typically $50 to $85	Not applicable	$45 (April 9, 2026)
Second checked bag	Typically $60 to $99	Not applicable	$55 (April 9, 2026)
Free bags for elites	Bundle: The Works	Not applicable	A-List Preferred + Choice Extra + Rapid Rewards cards
Seating model	Assigned, most seats add-on	Not applicable	Assigned as of Jan 27, 2026
Change fees	$99 outside 7 days, up to $99 within 7	Not applicable	None on most fares
Loyalty subscription	GoWild Pass ($199 Summer 2026)	Not applicable	Not offered
Network shape	Point-to-point from Denver hub, wide but thin	Not applicable	100+ dest, dense mid-continent
Best-fit traveler	Solo, flexible, packs light	Not applicable	Family, flexible plans, elite / cardholder
Route pickup post-Spirit	Some Fort Lauderdale, Orlando, Denver pairs	Absorbed by others	Some Vegas, Phoenix pairs
ShopBack angle	Book flights via ShopBack partners on hotel/car	Not applicable	Book flights via ShopBack partners on hotel/car

The pattern: Frontier wins base fare on flexible solo trips. Southwest wins total cost on family, change-prone, or elite-anchored trips. Spirit is not a live choice.

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Total-cost math: when does Frontier actually beat Southwest in 2026

The single mistake travelers make in 2026 is comparing headline base fares between Frontier and Southwest. What matters is the total cost after bags, seat, and change risk are added.

Solo traveler, personal item only, flexible date, midweek. Frontier wins clearly. The base fare gap of $30 to $80 versus Southwest usually holds because the traveler pays zero add-ons: no carry-on, no seat selection (auto-assigned aisle or window is acceptable), no bag. On a Denver-to-Orlando trip, Frontier at $59 base plus $14 in taxes often beats Southwest Basic at $99 for the same day. Break-even flips only if the traveler needs overhead carry-on.

Solo traveler, one carry-on overhead, flexible date. Break-even. Adding a $60 to $99 Frontier carry-on typically closes the gap or flips it to Southwest, which lets the carry-on ride free. The exact answer depends on route and add-on timing. For flexible solo travelers who cannot fit into a personal item, Southwest tends to win.

Family of four, one checked bag each, fixed vacation dates. Southwest wins clearly. Frontier's four checked-bag fees at $60 to $85 each land at $240 to $340 one-way. Southwest's four checked bags at $45 first plus (if the family stacks a Rapid Rewards credit card) two free elite bags land materially lower. Add change-fee risk on Frontier for anyone traveling with kids where a fever or a snow day happens; Southwest's no-change-fee policy removes that risk entirely.

Solo traveler on GoWild Pass. Frontier can win by a mile if the traveler flies at least 4 to 6 round-trips inside the pass window, packs in a personal item, and can absorb the schedule volatility. The Summer 2026 GoWild Pass at $199 through August 31, 2026 amortises at roughly $17 per one-way over 12 flights, which beats every other US budget-airline route on paper. The catch: blackout dates on major holidays and no guarantee of specific dates.

Family of four flying to Hawaii. Southwest wins clearly. Rapid Rewards points sit at 25,000 to 40,000 one-way for a Hawaii flight in most windows, and Southwest is the only budget-tier US carrier flying nonstop from mainland to Honolulu, Maui, Kona, and Lihue. Frontier does not serve Hawaii nonstop from most mainland hubs; Spirit no longer serves it at all.

How ShopBack fits. Compare hotels via ShopBack Travel Planner before booking the destination-side lodging. On a $1,200 four-night Hawaii hotel booking, even a 3 to 5 percent cashback rate at the OTA partner via ShopBack lands at $36 to $60 back, which is a meaningful offset against the family's flight bill, and it stacks on top of whichever airline the family flies.

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Route networks: where each airline is strongest in 2026

Route network matters more in 2026 than in previous years because Spirit's exit reshuffled which secondary airports have budget-tier coverage at all.

Southwest's network in 2026. Southwest serves over 100 domestic destinations plus Hawaii, Puerto Rico, the Caribbean, and Mexico. The strongest nonstop density runs through Denver, Nashville, Chicago Midway, Baltimore, Dallas Love Field, Phoenix Sky Harbor, Las Vegas, Kansas City, and Houston Hobby. This is the deepest budget-tier US network, and the mid-continent hub layout means most cross-country trips have at least one Southwest nonstop or a same-carrier one-stop.

Frontier's network in 2026. Frontier operates a point-to-point network from a Denver hub, with a wide but thinner map than Southwest. The strongest coverage is Denver to Orlando, Fort Lauderdale, Las Vegas, Phoenix, Chicago O'Hare, Atlanta, and Miami. Many secondary markets are served two to four days a week rather than daily, which means missing a Frontier flight can mean waiting 48 hours for the next one. For any flexible traveler willing to build a trip around Frontier's schedule, the network is fine; for date-locked travel, it can be brittle.

Where Spirit used to fly (now covered by others). Fort Lauderdale to San Juan is now served by Frontier and Southwest. Orlando to secondary Northeast airports is now Breeze plus Frontier. Vegas to Phoenix and other Southwest hubs is now Southwest plus Frontier. Charleston SC and Provo are Breeze. Akron, Fort Wayne, and Manchester NH are Breeze plus Allegiant. If your baseline was a Spirit route, cross-check the specific city pair on Google Flights before assuming a 1:1 replacement exists.

How ShopBack fits. Once the airline and route are set, compare hotels via ShopBack Travel Planner before booking the destination-side hotel. The hotel booking is often the largest single dollar item in the trip, and cashback layers on top of any hotel loyalty program at the same time. Start at shopback.com/travel for the destination search.

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When to skip all three and pick a legacy carrier

Not every US domestic trip should be a budget-airline booking in 2026. Skip Frontier and Southwest if any of the following applies:

• You need same-day rebook flexibility across multiple carriers. Only legacy carriers (Delta, American, United) offer reliable interline rebooking during weather or mechanical delays. Southwest can rebook you on its own next flight, but not on a competitor.
• You are flying on a fully-refundable government or corporate fare. The corporate travel policy typically restricts to Big 3 carriers with GDS-loaded fares. Frontier and Southwest often are not options.
• You need a lie-flat seat or a premium cabin experience. None of the three offer a true business-class cabin domestically. Frontier's Stretch seat and Southwest's Choice Extra are extra legroom, not a premium cabin.
• You are chasing legacy-carrier elite status milestones. Every dollar spent on Frontier or Southwest is off-map for building Delta Medallion, American AAdvantage Elite, or United MileagePlus Premier miles. If your household has active status-run, the budget-airline discount is a false economy.
• You are booking a codeshare with an international carrier. Frontier and Southwest do not codeshare with major foreign carriers. If you need one-ticket protection on a Star Alliance, oneworld, or SkyTeam through-fare, book the legacy carrier.

For every one of these traveler shapes, the ShopBack angle still lives in the hotel-and-car booking. Compare hotels via ShopBack Travel Planner before booking; the flight can be legacy while the hotel earns cashback.

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Frequently asked questions

Which is cheapest for US domestic travel in 2026: Frontier, Spirit, or Southwest?

As of mid-2026, Spirit is no longer a choice; the airline ceased operations on May 2, 2026 in a court-supervised wind-down. Between the remaining two, Frontier typically posts the lowest base fare on trunk domestic routes when the traveler packs light and skips add-ons, while Southwest usually wins on total trip cost once you factor in bag fees, change flexibility, and how often Frontier's carry-on fee ($60 to $99) closes the gap. For a family of four on a school-break week, Southwest is often cheaper end-to-end than Frontier once bags are added.

Are Spirit Airlines flights still operating in 2026?

No. Spirit Airlines wound down all operations on May 2, 2026 after its second Chapter 11 restructuring failed, per CNN and NPR reporting. Spirit was the first major US airline in roughly 25 years to shut down for financial reasons. Passengers holding future Spirit tickets were directed to seek refunds through their card issuer or DOT rules; some Spirit routes were absorbed by Frontier, Southwest, Breeze, and JetBlue, though fares on former Spirit routes rose about 11 percent within weeks according to Hopper.

How much does Southwest charge for checked bags in 2026?

As of April 9, 2026, Southwest charges $45 for the first checked bag and $55 for the second on most Basic and Choice fares, up from an initial $35/$45 introduced when Bags Fly Free ended on May 28, 2025. Two free checked bags remain for A-List Preferred elites, Choice Extra fare holders, active-duty military, and qualifying Rapid Rewards credit cardholders. Carry-on plus one personal item are still free at typical size limits.

What does Frontier charge for carry-on bags in 2026?

Frontier charges roughly $60 to $99 for a carry-on bag stored in the overhead bin in 2026, with prices lowest when added at the initial booking and highest at the gate. A personal item that fits under the seat in front remains free. Frontier's fee model means the cheap base fare often lands close to Southwest's total once a carry-on is added, so the price gap depends heavily on how light you pack. Confirm the current fee with the Bag Price Checker at flyfrontier.com before you book.

When did Southwest end open seating?

Southwest ended open seating for flights departing on and after January 27, 2026, ending 54 years of the boarding-group-and-pick-a-seat model. Assigned seating went on sale for those flights starting July 29, 2025. Basic fare passengers no longer get complimentary seat selection and are assigned a seat at check-in, similar to the basic economy fares on Delta, American, and United.

Should you buy the Frontier GoWild Pass for US domestic travel in 2026?

For flexible solo travelers who can fly midweek, pack in a personal item, and tolerate schedule changes, the Frontier GoWild Pass at $199 for the 2026 Summer version (available for purchase through August 31, 2026 for travel through January 4, 2027) can pay back after two or three round-trips. The pass unlocks unlimited seats on select routes when Frontier releases inventory, typically the day before departure. It is not a fit for travelers who need fixed dates, bring a carry-on that must go overhead, or fly on peak holiday windows blacked out by the pass.

Can I earn cashback when booking US domestic flights on ShopBack?

Compare hotels via ShopBack Travel Planner before booking, then click through to a supported partner such as Booking.com, Hotels.com, or Expedia to earn cashback on eligible bookings. For US domestic flights specifically, the strongest cashback path is usually booking the flight-plus-hotel or hotel-plus-car bundle at an online travel agency partner rather than direct at Frontier or Southwest. Activate cashback via ShopBack before checkout and complete the booking in a single session so tracking holds.

Compare US airline route networks for cross-country travel in 2026?

For nonstop transcontinental coverage on a budget-tier carrier, Southwest wins clearly in 2026: over 100 domestic destinations with strong nonstop density in mid-continent cities like Denver, Nashville, Chicago Midway, and Baltimore. Frontier operates from a Denver hub with a wide but thinner network of point-to-point routes, with many markets served only two to four times a week. For niche coast-to-coast city pairs and secondary airports (Provo, Charleston SC, Akron), Breeze Airways has filled a growing share of the former Spirit gap.

Do budget airlines let you change flights for free in 2026?

Southwest remains the only major US airline with no change or cancel fees in 2026 across most fare types; Basic fare changes are still allowed with a difference in fare, and Choice and above allow same-day changes at no cost. Frontier charges $99 for changes more than seven days out and up to $99 within seven days on standard fares, with waived fees on Bundles that include The Works. This flexibility gap is often the reason Southwest's higher headline fare works out cheaper on trips where schedules move around.

Where does ShopBack fit into US domestic trip planning?

Compare hotels via ShopBack Travel Planner before booking to line up cashback across supported hotel and OTA partners on the same trip. Start at shopback.com/travel to see live cashback offers alongside your itinerary, then click through to Booking.com, Hotels.com, Expedia, or Priceline for the hotel-and-car portion of the trip. Cashback via ShopBack posts to the ShopBack account separately from any airline loyalty points or credit-card rebate earned on the same purchase.

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Key takeaways

• The 2026 US budget-airline map has two live choices, not three: Frontier and Southwest. Spirit ceased operations on May 2, 2026 in a court-supervised wind-down.
• Frontier is the last national ULCC and usually posts the cheapest base fare when the traveler packs into a personal item and stays flexible on dates.
• Southwest is the strongest pick for families, flexible planners, elites, and Rapid Rewards cardholders; the checked-bag fees rose to $45 first bag and $55 second bag on April 9, 2026, but two free bags still ride along with A-List Preferred, Choice Extra, active-duty military, and qualifying Rapid Rewards cards.
• Southwest ended open seating on January 27, 2026; Basic fare passengers are auto-assigned seats at check-in, and Choice tiers unlock seat selection at booking.
• Frontier's GoWild Pass at $199 for Summer 2026 (buy through August 31, 2026, travel through January 4, 2027) is a strong fit for solo flexible travelers who fly 4 or more round-trips in the window.
• Former Spirit routes were partially absorbed by Frontier, Breeze, JetBlue, and Southwest, though average fares on those city pairs rose roughly 11 percent within weeks.
• Total-cost math for a solo personal-item-only trip usually favors Frontier; total-cost math for a family of four on fixed dates usually favors Southwest.
• Skip both budget airlines when you need interline rebooking, a premium cabin, corporate GDS fares, or elite status credit on a legacy carrier.
• Compare hotels via ShopBack Travel Planner before booking so the hotel-and-car legs of the trip earn cashback even when the flight itself does not.
• Verify current bag fees and route schedules at flyfrontier.com and southwest.com before you commit; fee grids and seasonal schedules change through the year.

💡 Plan your US trip on ShopBack Travel Compare hotels and rentals to layer cashback on the parts of the trip that live outside the airline.

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Sources

• NPR, Spirit Airlines ceases operations after escalating financial struggles (May 2, 2026)
• CNN, Spirit Airlines canceled all flights and is going out of business (May 2, 2026)
• Upgraded Points, Southwest Airlines Increasing Checked Bag Fees on April 9
• CBS News, Southwest sets its first checked bag fee, starting at $35
• CNBC, Southwest ends open seating after 54 years (January 27, 2026)
• Southwest Airlines, Assigned Seating customer enhancements
• Forbes Advisor, Frontier Airlines Launches Its 2026 GoWild Summer Pass for $199
• Frontier Airlines, Optional Services and Bag Fees
• Fortune, Spirit Airlines bankruptcy exit and jet fuel liquidation (April 20, 2026)

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Disclaimer

The views and recommendations expressed in this article are those of the author.

Airline fees, bag pricing, seating policies, route schedules, and loyalty program terms are subject to change. Please verify details directly with Frontier Airlines, Southwest Airlines, or the relevant travel provider before booking. Where third-party reporting differs from the airline's own published figures, this article defers to the airline's own page or a primary-source news report, and readers should reconfirm current terms before assuming any specific fee or policy.

This article is intended for general informational purposes only and should not be considered professional travel advice. US domestic travel value depends on individual routing, timing, and packing patterns; we recommend running the total-cost math on your specific trip before committing to a fare class or a loyalty pass.

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