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Discovery

Cheap Flights from Denver — Frontier's Backyard and the $19 Fare Machine

Bryan MendezJan 20265 min read

Frontier runs $19 fare sales from Denver. Nineteen dollars. As in, less than the airport parking. I once booked DEN to Las Vegas for $23 round-trip, which I am still not fully convinced was legal. Denver International has transformed into one of America's most important airports for budget travelers — it is Frontier's hometown hub, Southwest has a massive presence, and the international network is growing fast.

The catch: Denver is landlocked. You are 4 hours from either coast, which means international flights are either expensive directs or require a cheap positioning flight to a coastal hub. But Frontier sells those positioning flights for the price of a burrito. So it works out.

The Airport

DEN — One massive airport. Concourse A is United's hub. Concourse C is Frontier's home base. A Line train to Union Station downtown costs $10.50 and takes 37 minutes. Security lines can be brutal — Clear or PreCheck pays for itself here. Note: DEN is under construction through 2028. Allow extra time and check terminal updates before your flight.

Nearby alternative: Colorado Springs (COS), 1.5 hours south. Frontier flies there too and fares are sometimes cheaper.

Denver's Domestic Superpower

Before we talk international — DEN's domestic network is where budget travelers win the hardest:

Las Vegas: $50-120 — Frontier / Southwest — 2h
Phoenix: $60-130 — Frontier / Southwest — 2h
Los Angeles: $70-150 — Frontier / Southwest — 2.5h
San Francisco: $80-160 — Frontier / Southwest — 2.5h
Seattle: $90-170 — Frontier / Alaska — 3h
Chicago: $80-150 — Frontier / United — 2.5h
New York: $100-200 — Frontier / JetBlue — 4h

Frontier runs $19-49 fare sales from Denver regularly. Sign up for their email alerts. These are not theoretical — they are weekly occurrence prices for midweek travel.

Denver to Latin America — Mexico Is the Sweet Spot

What You Should Expect to Pay (Round-Trip)

Cancun: $200-320 — Frontier / United — 4h
Mexico City: $250-380 — United / Volaris — 4h
Puerto Vallarta: $220-350 — Frontier / Southwest — 3.5h
Cabo: $200-320 — Southwest / Frontier — 3h
Costa Rica: $350-500 — United / Southwest — 5h

Frontier's Denver to Cancun goes on sale frequently. Sub-$250 round-trips are not unusual.

Sample Itineraries

Mexico Beach + City (2 weeks) — DEN to Mexico City ($280). Bus to Oaxaca ($40). Overland to Puerto Escondido. Fly to Cancun ($100). Cancun to DEN ($220). Total flights around $600.

Southwest US Road Trip (10 days) — DEN to Las Vegas ($60 on Frontier). Rent a car — Vegas to Grand Canyon to Sedona to Phoenix. Phoenix to DEN ($70). Total flights around $130.

Denver to Europe — Icelandair Is Your Best Friend

What You Should Expect to Pay (Round-Trip)

Reykjavik: $350-500 — Icelandair — 7h
London: $450-650 — British / United — 9h
Frankfurt: $500-700 — Lufthansa / United — 10h
Paris: $520-720 — United / Air France — 10h
Munich: $480-680 — Lufthansa — 10h

Icelandair to Reykjavik is the move. Free stopover in Iceland, then continue to mainland Europe. Often $150-200 cheaper than direct flights to London or Paris.

Sample Itinerary

Iceland + Europe (2 weeks) — DEN to Reykjavik ($380 on Icelandair with stopover). Budget carrier to Amsterdam ($120). Overland to Paris. United return Paris to DEN ($500). Total flights around $1,000.

Denver to Asia — Position to the Coast

Connections required, but the math works when you use Frontier:

Tokyo: $650-850 — DEN-LAX-NRT — 15h
Seoul: $700-900 — DEN-SFO-ICN — 16h
Bangkok: $700-900 — DEN-NRT-BKK — 19h
Bali: $800-1000 — DEN-NRT-DPS — 22h

The play: position to LA or San Francisco on Frontier ($50-80), then book a separate Asia ticket. This often saves $200+ compared to booking through from Denver.

Sample Itinerary

Asia on a Budget (3 weeks) — DEN to Los Angeles ($60 on Frontier). LAX to Tokyo ($550 on Zipair). Budget carrier to Bangkok ($180). Return Bangkok to DEN via LAX ($600). Total flights around $1,390.

Denver-Specific Moves

Master Frontier — The Discount Den membership costs $60/year and gives you 20-50% off already low fares. Family pooling for free bags. Book Tuesday and Wednesday for the lowest prices. This is the single highest-value move for Denver-based budget travelers.

Southwest for flexibility — No change fees, ever. Two free checked bags. Points worth roughly 1.5 cents each. Denver is a focus city, so coverage is broad.

Position for international — Frontier to LAX or SFO for $50-80, then book a separate international ticket. Total often beats direct DEN pricing. Works especially well for Asia.

United mistake fares — Denver gets a disproportionate number of error fares through United. Watch the deal accounts.