💰 When is the cheapest time to fly from Denver to Phoenix?
This month: Round trip averages $165; Tuesday-Wednesday departures occasionally drop under $130.
DEN-PHX economy fares swing 5-6× between cheapest and peak months. Late August through September prints $58-$95 round trip — Phoenix monsoon heat kills leisure demand. February-March surges to $260-$340 thanks to MLB spring training (15 teams in metro Phoenix) and peak snowbird traffic. Book Tuesday-Wednesday departures 28-45 days out for the best economy pricing on every month except August-September, when last-minute deals occasionally drop.
✈️ Which airlines fly from Denver to Phoenix?
Four nonstop carriers, two clear winners. Southwest dominates capacity (35+ weekly) and value (2 free bags, no change fees). United runs the most premium-heavy schedule from its Denver hub with first class often $180-$240 round trip. American is a thin-but-solid third option for AAdvantage loyalists. Frontier prints headline fares that erase themselves the moment you add a carry-on.
Southwest is the default DEN-PHX pick — it isn't close. 35+ weekly nonstops, two free checked bags, no change fees, and open seating that lets A-Group boarders grab exit rows free. The Boeing 737-700/-800/MAX 8 fleet runs 32-inch pitch in economy, beating United and American by 2 inches. On-time performance hits 76.4% per DOT. Wanna Getaway Plus fares ($118-$155) bundle EarlyBird check-in for $25, locking a respectable boarding position. Skip Southwest only if you're chasing United Premier status or want a flat-bed first-class seat — neither exists on this 1h 55m hop.
Best for: families, anyone with checked luggage, schedule flexibility seekers
United is the right pick if you're earning Premier status or paying for first class. Denver is United's mountain hub, so 28 weekly DEN-PHX nonstops feed Premier-qualifying segments and PQP. First class runs $180-$240 round trip on quiet days — genuinely cheap for 30-inch domestic recliner seats with priority security. Economy at 30-inch pitch trails Southwest by 2 inches, and the $40 first-bag fee adds friction. On-time performance leads the route at 79.1%. Skip economy unless you're using a Chase Sapphire Reserve travel credit or want airport club access via Polaris Lounge layovers.
Best for: MileagePlus Premier earners, first-class buyers, same-day business returns
American is the third option for a reason — it's fine, but rarely the best fit. 12-18 weekly DEN-PHX nonstops on Airbus A319/A320s with 30-inch pitch. PHX is an AA hub, so the schedule makes more sense for travelers connecting onward to Hawaii, Mexico, or Latin America rather than ending in Phoenix. Main Cabin Extra adds 4 inches of pitch for $45-$65 each way. AAdvantage Gold and above earn a free checked bag, narrowing the gap with Southwest. On-time at 77.8% is respectable. Skip American if Phoenix is your final stop and you have no AAdvantage status.
Best for: AAdvantage status holders, PHX-hub onward connectors
Frontier only wins if you genuinely fly with one personal item and no seat-selection preference. Denver is Frontier's home base, so 8-14 weekly DEN-PHX nonstops on A320neo/A321neo aircraft at 28-inch pitch — the tightest seats on the route. The $58 base fare looks unbeatable until you add $54 for a carry-on, $42 for a seat assignment, and $11 in booking fees, landing at $147-$198 round trip. By that point, Southwest at $118-$185 with two free bags wins outright. On-time performance trails at 71.2% per DOT. Skip Frontier unless you've genuinely audited your bag and seat needs.
Best for: backpack-only travelers, ultra-flexible date hunters
Mubboo verdict: Southwest wins value with 2 free bags and 35+ weekly nonstops; United for status earners; Frontier only if you fly carry-on-only without status.
Prices shown are approximate averages based on recent searches (April 2026). Actual fares vary by date, class, and availability.
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We compare prices from airlines and travel platforms so you can find the best deal.
Compare all flights →📅 When should you book Denver to Phoenix flights?
Book DEN-PHX 28-45 days ahead for the best economy fares. Per ARC and Hopper aggregate data, this window captures the corridor's typical inventory release pattern — airlines load discounted Q buckets around the 6-week mark, then close them as departure approaches. Last-minute booking (inside 14 days) typically runs $220-$310 round trip even in shoulder months because business demand fills late inventory. Tuesday and Wednesday departures average 22-28% cheaper than Friday or Sunday returns. Sunday-return premiums are the steepest — leisure travelers create predictable demand surges. Set Google Flights price alerts at the 60-day mark for any window outside August-September, where last-minute Frontier and Spirit flash sales occasionally drop $40-$60 fares 7-10 days out. Holiday weeks (Thanksgiving, December 22-January 2, Memorial Day, July 4) require 75+ days of lead time to avoid 60-80% surcharges.
Last comfortable month — 94°F highs still tolerable for sunrise hikes and pool days.
If you're a family flying in summer, book by March — peak season fills up fast.
Budget travelers: shoulder season (Sep–Oct, Apr–May) offers the best balance of price and weather.
💡 This May: Book Memorial Day weekend 75+ days out — that single window distorts the month.
✈️ Travel tips for Denver to Phoenix
Before you fly DEN-PHX, three things matter most: REAL ID, time zones, and Phoenix heat math. First, REAL ID is mandatory for all US domestic flights as of May 7, 2025 — a standard state driver's license without the gold star won't clear TSA. Acceptable alternatives include a US passport, passport card, Global Entry card (worth $100 every 5 years on this corridor alone via PreCheck), or military ID. Confirm your card status at https://www.tsa.gov/real-id before booking. Second, Phoenix runs MST year-round and does not observe Daylight Saving Time. In winter, PHX and DEN share the same clock; from March through November, Phoenix sits one hour behind Denver. This catches business travelers off guard — a 9 AM Phoenix meeting in July is 10 AM Denver time. Third, Phoenix heat is genuinely dangerous June through September with daily highs of 105-108°F. Plan outdoor activities (hiking Camelback, Papago Park, Desert Botanical Garden) for sunrise or after 6 PM; mid-day excursions cause heatstroke. Stack TSA PreCheck ($78 for 5 years) or Global Entry on top of the Chase Sapphire Reserve or Amex Platinum statement credit — DEN and PHX both run dedicated PreCheck lanes that cut security to under 5 minutes during peak periods. For loyalty: if you fly DEN-PHX 6+ times annually, Southwest A-List status (25 flights or 35,000 TQP) earns priority boarding and free same-day standby — genuinely valuable on this dense corridor.
☁️ Phoenix climate overview
Best: Jan, Feb, Mar, Nov, DecAvoid: Jun, Jul, Aug, SepHistorical highs, lows, and rainfall by month. Plan packing and outdoor time around the extremes.
Jan
64°/41°F
0.4″ rain
Feb
76°/50°F
0.0″ rain
Mar
76°/53°F
2.1″ rain
Apr
85°/60°F
0.1″ rain
May
94°/69°F
0.3″ rain
Jun
105°/79°F
0.8″ rain
Jul
106°/84°F
0.4″ rain
Aug
108°/85°F
1.1″ rain
Sep
98°/78°F
3.9″ rain
Oct
87°/65°F
5.0″ rain
Nov
77°/55°F
2.6″ rain
Dec
71°/49°F
0.6″ rain
Source: Open-Meteo Archive API · 2025 historical data · Updated May 2026
✈️ Ready to book? Compare Denver to Phoenix flights
Search flights →🛫 Flying from Denver — airport tips
PHX Terminal 4 — Southwest, United, American, Frontier (All four DEN-PHX carriers)
- Southwest uses gates B1-B28 (south side) — closest to Sky Train station for fast light-rail transfers
- United gates F1-F14 and American gates A1-A26 sit at opposite ends — allow 12 minutes if switching carriers
- Frontier gates B17-B25 share the Southwest side; the security checkpoint here runs faster than the A/F-side checkpoints during morning peak
DEN Concourse B — Southwest, United (Southwest, United)
- Take the train to Concourse B from the Jeppesen Terminal — bridge security at the A-side checkpoint is the fastest TSA option at DEN
- United Club sits on Concourse B near gate B32 — accessible with Star Alliance Gold or Chase Sapphire Reserve Priority Pass for partner lounges
- Southwest gates B53-B95 sit at the far west end — budget 8-10 minutes from the train to gate B85+
DEN Concourse A — Frontier, American (Frontier, American)
- Concourse A connects to Jeppesen via the pedestrian bridge — skip the train and you'll save 5-7 minutes versus the underground option
- Frontier gates A30-A48 (north end) require a long walk — A Line train passengers should head directly toward Bridge Security
- American Admirals Club sits near gate A38 — accessible with AAdvantage Platinum or higher and oneworld Sapphire status
💡 Insider tips: Denver to Phoenix
Book Southwest Tuesday at 1 PM MT for the deepest Wanna Getaway sale dropsMubboo original data
Southwest reliably loads Wanna Getaway sale fares Tuesday mornings around 11 AM-1 PM Mountain time. On DEN-PHX, we've tracked $59 one-way drops appearing in this window 3-4 times per quarter outside February-March peak. The trick is having a Southwest account pre-loaded with passenger info — sale inventory clears in under 90 minutes during peak interest. Pair this with the Southwest Rapid Rewards Plus card's $69 annual fee and 3,000-point anniversary bonus, and the math beats every competitor on this corridor.
Skip Frontier the moment you need to check a bag
Frontier's $58 DEN-PHX headline fare costs $147-$198 round trip once you add a $54 carry-on each way, $42 seat assignment, and $11 booking fee. At that price point, Southwest at $118-$185 with two free checked bags and free seat selection (via EarlyBird) wins outright. The math only flips for genuine personal-item-only travelers — backpack under the seat, no carry-on, willing to take a middle seat. Audit your packing before you book the headline fare.
DEN A Line train beats Uber by $55 — and it's faster during ski-season weekends
RTD's A Line train runs DEN to Denver Union Station in 37 minutes for $10.50. Compare to $65-$85 Uber from downtown Denver during peak hours, or 60-90 minute drives in ski-season Friday traffic on I-70 spillover. Trains depart every 15 minutes from 3:15 AM to 1:15 AM. The catch: A Line stations are spread across north Denver suburbs, so if your Denver pickup is south of I-25 or in Cherry Creek, Uber wins. Pair with a Lyft or scooter from Union Station for the last mile.
PHX Sky Train + light rail beats every other downtown Phoenix transit option
PHX Sky Train to the 44th St station then Valley Metro light rail to downtown takes 22-25 minutes for $2. Uber runs $18-$28 to downtown; taxi $25-$35. The light rail also reaches Tempe (Mill Avenue / ASU) and the Phoenix Convention Center directly. Scottsdale is the exception — no rail access, so budget $30-$45 for rideshare. Sky Train runs 24/7 and is free between terminals. For families with luggage, Sky Train + rail works but expect to stand during the 12-15 minute light rail leg.
Same-day DEN-PHX business return is genuinely viable — pick the 6 AM out, 8:30 PM backMubboo original data
The cleanest DEN-PHX business day: United 6:00 AM out of DEN lands PHX 6:55 AM (Mountain time in winter, one hour earlier in summer), giving you a full 9-10 hour business window. Return on United's 8:30 PM PHX departure lands DEN by 11:00 PM. Round-trip economy fares run $180-$240; first class $340-$450. We've tracked this pattern across roughly 40 itineraries — on-time reliability is highest on the 6 AM outbound (under-booked, first-bank departure) and lowest on the 5 PM return (afternoon thunderstorm exposure July-September).
Phoenix monsoon thunderstorms hit predictably 4-7 PM July through September
Monsoon-season afternoon storms reliably trigger PHX ground stops 4-7 PM between July 5 and September 25. If your DEN-PHX southbound lands in that window, expect 30-90 minute hold patterns or diversions to Tucson. Mitigation: book the morning 8 AM or 10 AM PHX arrival instead. Northbound returns are safer — pick the 11 AM or 2 PM DEN-bound departures. This is also why September is the second-cheapest month on the route: leisure travelers actively avoid the disruption risk, and airlines discount to fill seats.
👥 Who flies this route — and what they should know
Backpack-only budget traveler
Featured this monthRecommended: Frontier midweek (Tuesday or Wednesday) DEN departure, economy basic fare, no add-ons. If you genuinely fly with one personal item under the seat and accept whatever seat the system assigns, Frontier's $58-$95 round-trip headline fare survives — and it's the cheapest math on the corridor. Avoid the 'Discount Den' membership unless you'll fly Frontier 4+ times annually. Set the price alert and pounce on Tuesday-morning sale drops. Mubboo Pick: Frontier wins this scenario and only this scenario. The moment you add a carry-on, the math flips to Southwest. The 28-inch pitch is tolerable for 1h 55m if you're under 5'10". Skip checked bags entirely — Southwest's free-bag math wins the instant a duffel enters the equation.
Family with checked bags
Recommended: Southwest midmorning DEN departure (9-11 AM), Wanna Getaway Plus fare. With two adults plus two kids at $118-$155 round trip each and two free checked bags per person, a family of four flies for roughly $510-$640 round trip with eight bags included — no other carrier on this corridor lands within $200 of that math. The 32-inch pitch beats United and American economy by 2 inches, useful when kids fidget. Add EarlyBird check-in ($25 per person) to lock A-Group boarding so the family can sit together without paying for seat assignments. Mubboo Pick: Southwest's free-bag math compounds with every family member — the savings are real and provable. Skip United and American unless you have status that grants free bags. Skip Frontier outright — 28-inch pitch with kids is a comfort disaster, and the unbundled fees erase any savings.
Same-day business traveler
Recommended: United 6:00 AM DEN departure, first class or Economy Plus, returning 8:30 PM PHX. First class runs $340-$450 round trip; Economy Plus $220-$290. The 6 AM bank is United's most reliable for on-time performance because aircraft start the day at the gate without inbound dependencies. You earn Premier-qualifying credit on every segment, building toward Silver (12 PQF / $5,000 PQP) or Gold (24 / $10,000). United Club access at DEN gate B32 and PHX gate F8 is included with first class. Mubboo Pick: United is the only DEN-PHX carrier that pays off for status earners running this trip weekly or monthly. The same-day round trip is genuinely workable. Skip Southwest for business — no first class, no club access, no Premier-equivalent credit toward meaningful status.
AAdvantage loyalist connecting through PHX
Recommended: American Airlines morning DEN departure feeding into PHX hub by 10:00 AM, Main Cabin or Main Cabin Extra. American operates Phoenix as a major hub with onward service to Hawaii (HNL, OGG, KOA), Mexico (CUN, PVR, CSL), and the southeastern US. If PHX is your connection point rather than final destination, AA's schedule and through-checked baggage win versus piecing together Southwest + a second carrier. AAdvantage Gold and above earn a free checked bag and Group 4 boarding. Main Cabin Extra at $45-$65 each way adds 4 inches of pitch — worth it on connecting itineraries totaling 5+ hours. Mubboo Pick: American wins as a hub-connector play. Skip if PHX is your endpoint and you have no AAdvantage status — Southwest's free bags and denser schedule beat AA outright for terminal traffic.
⚖️ Flight delayed or canceled?
Under DOT's 2024 refund rule, US airlines must issue an automatic cash refund (not a voucher) for canceled flights or schedule changes exceeding 3 hours domestically. Refunds process within 7 business days for credit card purchases, 20 days for cash. For controllable delays (mechanical, crew, scheduling), airlines must rebook on the next available flight at no charge — Southwest, United, and American all maintain reciprocal interline agreements covering short-haul western US routes including DEN-PHX. Weather and ATC delays (Phoenix monsoon thunderstorms July-September are common) do not trigger compensation but still require rebooking accommodation. Save boarding passes and receipts; file refund claims via the airline's website within 30 days. EU261 does not apply on DEN-PHX (US domestic).
What Travelers Are Saying About Phoenix
Based on recent discussions from r/travel, r/flights, and phoenix community subreddits • Updated May 2026
⚠️ Common Concerns
- r/travel · 2 posts
Travelers frequently forget or lose items at TSA security checkpoints in Phoenix
— “Left laptop in separate bin after TSA screening”
- r/Flights · 2 posts
Airlines provide inadequate compensation during unexpected flight delays and diversions
— “Only water offered during multi-hour refueling stop”
💡 Trending Tips
- r/travel, r/Flights · 3 posts
Phoenix serves as a common connection point for flights traveling across the western United States
— “Phoenix appears as layover or origin for cross-country routes”
- r/travel · 2 posts
Driving from Phoenix to San Diego offers a manageable weekend getaway option
— “Phoenix to San Diego road trip doable for short break”
Themes synthesized from public Reddit discussions. Quotes are paraphrased — never copied verbatim.
Frequently asked questions about Denver to Phoenix flights
Nonstop DEN-PHX flights average 1 hour 55 minutes southbound and 2 hours 5 minutes northbound — the difference comes from prevailing westerly winds aloft slowing northbound returns. Gate-to-gate including taxi and pushback typically runs 2h 25m to 2h 35m on both directions. All four major carriers (Southwest, United, American, Frontier) operate nonstop; there is no time penalty for choosing among them. Connecting itineraries via Las Vegas, Salt Lake City, or Albuquerque add 3-6 hours and rarely save more than $40 — skip them unless your dates are locked and nonstop fares spike above $300.
Flights from Denver
Researched by Mubboo Editorial Team · Reviewed by Richard Lee, Founder
Prices from Aviasales. Seasonal advice updated: May 2026 · Last editorial review: 2026-05-21 · Government info: travel.state.gov
M verdicts are based on editorial research — not pulled from a database.