Cheapest Flights Phoenix to Denver: Expert Insights for Smart Travelers
Flying between Phoenix Sky Harbor International Airport (PHX) and Denver International Airport (DEN) is one of the most competitive routes in the Southwest, offering travelers numerous opportunities to secure exceptional fares. This 600-mile corridor connects two major metropolitan areas and serves business professionals, leisure travelers, and adventure seekers heading to Colorado’s Rocky Mountains. Understanding the nuances of this route can help you save significantly on airfare while maintaining flexibility and convenience.
The Phoenix-Denver corridor features multiple daily flights from major carriers including Southwest Airlines, United, Frontier, and Allegiant Air. Competition on this route drives prices down, making it one of the most affordable domestic flights in the region. Whether you’re planning a weekend getaway to Denver’s vibrant downtown scene or a mountain adventure, knowing when and how to book can mean the difference between premium pricing and unbeatable deals.
Best Times to Book Flights Phoenix to Denver
Timing your booking strategically can result in savings of 30-50% compared to last-minute purchases. Industry data suggests that booking between 1-3 months in advance typically yields the lowest fares for this domestic route. Tuesdays and Wednesdays are traditionally the cheapest booking days, as airlines often release sales early in the week to fill remaining inventory before the weekend surge.
Early morning departures from Phoenix (before 8 AM) and late evening returns from Denver (after 6 PM) consistently offer lower fares than peak travel times. These less desirable flight times appeal primarily to business travelers who prefer mid-day schedules, allowing leisure travelers to capitalize on reduced pricing. Additionally, flying on Tuesdays through Thursdays rather than Friday-Sunday can save 20-40% on roundtrip tickets.
The sweet spot for booking Phoenix-Denver flights falls between 21-45 days before your intended travel date. During this window, airlines have optimized their pricing algorithms, removed the “last-minute” premium, but haven’t yet applied surge pricing for popular weekend travel. Avoid booking within 7 days of departure unless you’re flexible with times and dates, as prices spike dramatically during this period.
Airline Carrier Comparison for Phoenix-Denver Routes
Southwest Airlines dominates the PHX-DEN market with the highest frequency of daily flights and a loyal customer base. Their two free checked bags policy and lack of change fees make Southwest particularly attractive for budget-conscious travelers, even if base fares aren’t always the absolute lowest. Southwest operates approximately 8-10 daily roundtrip flights on this route, providing unmatched schedule flexibility.
Frontier Airlines consistently offers the lowest base fares on this corridor, often undercutting competitors by $30-60 per roundtrip segment. However, Frontier’s ultra-low-cost model charges for everything beyond the basic seat: carry-ons, checked bags, seat selection, and even beverages. For minimalist travelers with only personal items, Frontier represents genuine savings. Their Denver hub gives them operational advantages on this route.
United Airlines provides mid-range pricing with superior schedule options and connections to their extensive network. United’s MileagePlus frequent flyer program offers better earning potential on this route compared to competitors. Business travelers and those valuing premium cabin options find United’s product competitive, though base economy fares run higher than Frontier.
Allegiant Air operates limited service on this route with the absolute lowest published fares, often 40-60% below competitors. However, their spartan approach to amenities and reputation for ancillary fees means total trip cost frequently exceeds competitors. Allegiant works best for price-sensitive travelers comfortable with minimal frills.
For most travelers, Southwest offers the optimal balance of best airlines for frequent flyers benefits, transparency, and genuine savings. The two free checked bags alone justify slightly higher base fares compared to ultra-low-cost carriers for anyone traveling with luggage.
Strategic Booking Strategies for Maximum Savings
Implement a multi-pronged approach to secure the cheapest Phoenix-Denver flights. Begin by setting up price alerts on major travel aggregators 60 days before your intended travel date. These alerts notify you when fares drop, enabling real-time booking decisions. Monitor multiple platforms simultaneously—Google Flights, Kayak, Expedia, and airline websites directly—as pricing varies slightly across channels due to different commission structures.
Clear your browser cookies before searching for flights, as travel sites sometimes inflate prices for repeat visitors. Use incognito browsing mode to ensure you’re seeing base pricing without algorithmic manipulation. Alternatively, search from your mobile device, which often displays different pricing than desktop versions.
Consider one-way bookings instead of roundtrips when flexibility allows. Phoenix-Denver routes frequently show cheaper one-way pricing than roundtrip packages, particularly when booking outbound and return flights separately across different carriers. Calculate the total cost before assuming roundtrip bundles offer better value.
Join airline loyalty programs before booking, even if you don’t have status. Free enrollment takes two minutes and qualifies you for instant bonus miles or discounted fares. Southwest’s Rapid Rewards, United’s MileagePlus, and Frontier’s Frontier Miles all offer first-booking bonuses worth $20-50 in value.
Leverage airline ticket price trends by understanding seasonal fluctuations specific to the Phoenix-Denver corridor. Monitor historical pricing data on Google Flights’ price history tool, which displays 90-day price trends for your specific route.
Seasonal Pricing Patterns and Peak Travel Periods
Phoenix-Denver pricing follows distinct seasonal patterns driven by weather, holidays, and regional events. Winter months (December-February) see elevated prices as Denver’s ski season attracts visitors and Phoenix residents escape cold weather. Holiday periods—particularly Thanksgiving and Christmas—represent peak pricing, with fares often doubling normal rates.
Spring (March-April) offers exceptional value as ski season ends and spring break crowds disperse. Easter holiday travel disrupts these patterns temporarily, but late March and early April typically feature the year’s lowest fares. This shoulder season provides ideal conditions for budget travelers: pleasant weather in both cities and minimal pricing pressure.
Summer (June-August) shows moderate pricing increases as families travel and Denver hosts numerous outdoor festivals. However, summer remains less expensive than winter because Phoenix’s extreme heat discourages tourism, keeping overall demand moderate. Early summer (late May-early June) before school breaks offers better rates than July-August.
Fall (September-October) presents another excellent booking window. Post-summer, pre-holiday pricing remains reasonable while weather in both cities reaches perfection. Denver’s fall foliage and outdoor activities attract visitors without triggering the price premiums of winter ski season. October specifically offers some of the year’s best value.
Avoid booking during major Denver events including the National Western Stock Show (January), Colorado Wine Festival (September), and Oktoberfest celebrations. These events fill hotels and flights, driving prices upward. Similarly, Phoenix-specific events like spring training baseball (February-March) increase demand on this route.
Airport and Route Alternatives to Consider
While Phoenix Sky Harbor International (PHX) remains the primary airport, Phoenix-Mesa Gateway Airport (AZA) occasionally offers cheaper fares on budget carriers like Allegiant. The 40-minute drive east from downtown Phoenix means savings must exceed $20-30 per person to justify the additional travel time and expense. Similarly, Denver International (DEN) has no practical alternatives for this route.
Consider flying Phoenix to nearby Colorado Springs (COS) instead of Denver if your final destination permits. Colorado Springs lies 80 miles south of Denver and sometimes features lower fares, though you’ll need ground transportation to reach Denver. This strategy only works if you’re traveling to southern Colorado or have flexibility in your destination.
Reverse routing through intermediate hubs occasionally yields savings. Booking Phoenix to Las Vegas (LAS) to Denver, or Phoenix to Salt Lake City (SLC) to Denver, can sometimes cost less than direct flights. However, this only works when you have significant time flexibility and don’t mind the longer journey. Most direct flight passengers find this strategy impractical.
The flights from Philadelphia to Houston route illustrates how understanding alternative routings applies across different corridors. While your Phoenix-Denver route lacks comparable alternatives, the principle of exploring options remains valuable.
Frequent Flyer Program Benefits and Redemptions
The Phoenix-Denver route qualifies as an ideal frequent flyer redemption opportunity. Southwest Rapid Rewards requires 8,500-12,500 points for economy roundtrips on this route, translating to approximately $100-150 in value. With sign-up bonuses typically offering 40,000-50,000 bonus points, a single credit card application can fund multiple Phoenix-Denver trips.
United MileagePlus pricing for this route ranges from 12,500-25,000 miles for economy, with premium cabin upgrades available for 15,000-40,000 additional miles. United’s dynamic pricing means fares vary significantly based on demand, making this route potentially expensive during peak seasons.
Frontier’s rewards program offers minimal value on this route, as their low base fares make mile redemptions less attractive than cash purchases. Unless you’ve accumulated substantial Frontier miles, cash bookings typically provide better value.
Credit card sign-up bonuses represent the fastest path to free Phoenix-Denver flights. Southwest Rapid Rewards cards offer 40,000-75,000 bonus points (worth 4-8 free flights), while United cards provide 50,000-75,000 bonus miles. Strategic credit card applications timed with travel plans can eliminate airfare costs entirely.
Join elite frequent flyer programs if you fly this route quarterly or more frequently. United Silver status grants priority boarding and complimentary upgrades, while Southwest A-List provides boarding priority and 25% bonus earning. These benefits compound savings beyond discounted base fares.
Understand that best airlines for frequent flyers varies by individual travel patterns. For Phoenix-Denver specifically, Southwest’s high frequency and generous policies favor frequent flyers more than competitors.
FAQ
What’s the cheapest day to fly from Phoenix to Denver?
Tuesday through Thursday consistently offer the lowest fares on this route, with Wednesday typically being cheapest. Weekend travel (Friday-Sunday) commands 20-40% premiums. Early morning departures before 8 AM and late evening returns after 6 PM provide additional savings of 15-25%.
How far in advance should I book Phoenix to Denver flights?
Book 21-45 days before travel for optimal pricing. This window balances reduced last-minute premiums with avoidance of surge pricing for popular dates. Avoid booking within 7 days of departure unless you have flexible dates and times.
Which airline offers the cheapest flights on this route?
Frontier Airlines consistently publishes the lowest base fares, often $30-60 cheaper than competitors. However, their strict baggage and amenity fees mean total trip cost may exceed Southwest or United for travelers with checked luggage. Southwest provides the best overall value considering included benefits.
Are Phoenix-Denver flights cheaper than other Southwest routes?
Phoenix-Denver pricing falls within the mid-range for Southwest routes. Shorter routes (Phoenix-Las Vegas, Denver-Chicago) often feature lower absolute prices, while longer routes (Phoenix-Boston, Denver-New York) command premiums. However, per-mile pricing on Phoenix-Denver is competitive.
What’s the average cheapest fare for Phoenix to Denver?
Off-season roundtrip fares range from $150-250 during shoulder seasons. Peak winter and summer travel commands $250-400+ roundtrips. Historically low fares of $100-130 roundtrips occasionally appear during flash sales and promotional periods, though these are uncommon.
Can I save money flying into an alternative Denver airport?
Denver International (DEN) is the only commercial airport serving the Denver metro area. Colorado Springs (COS) 80 miles south occasionally shows lower fares, but ground transportation costs typically exceed any savings. This only benefits travelers whose final destination is southern Colorado.
Do connecting flights save money on this route?
Rarely. Direct flights dominate Phoenix-Denver due to competitive market dynamics. Connecting flights through hubs like Las Vegas or Salt Lake City typically cost more than direct flights, plus require significantly more travel time. Direct flights represent the best value on this route.
What’s included in budget airline fares on this route?
Frontier’s base fares include one personal item only. Carry-ons cost $30-45 and checked bags $35-50 each. Seat selection, beverages, and snacks cost extra. Allegiant’s model is similarly restrictive. Southwest includes two free checked bags and carry-ons, making their “higher” base fares often cheaper overall.
