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$58+ Cheap flights from Sky Harbor Intl (PHX) to Boulder, CO

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/26. Fares are subject to change and may not be available on all flights or dates of travel.
PHX — DEN
Mar 31 — Apr 71
Mon 3/31
Mon 4/7
1 adult, Economy
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Cheapflights Tip: The best prices from Phoenix Sky Harbor Intl to Boulder are usually found in August or February, booked 62 days in advance, depart on a Thursday or Friday and return on a Saturday

Cheap flight deals from Sky Harbor Intl to Boulder

Keep the following information in mind while searching for Sky Harbor Intl to Boulder flight deals. Data was last updated March 26, 2025.

Round-trip from

$107
(Cheapflightsfares)

One-way from

$58
(Kiwi.com)

Popular in

March

Cheapest in

August

Average price

$178
From Phoenix Sky Harbor Intl to Boulder
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One-way flight from Phoenix Sky Harbor Intl to Boulder
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Highest demand for flights based on searches. 3% potential increase in price ($4 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Find flight deals from Sky Harbor Intl to Boulder

Cheapest flights from Sky Harbor Intl to Boulder
Explore the most affordable flight options available from Sky Harbor Intl to Boulder. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 26, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 3/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1611:08 amPHX - DEN
Nonstop1h 56mFrontier
Tue 4/295:40 pmDEN - PHX
Nonstop2h 00mFrontier
Deal found 3/24$107
This American Airlines deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/228:34 amPHX - DEN
Nonstop1h 56mAmerican Airlines
Tue 4/298:09 amDEN - PHX
Nonstop2h 21mAmerican Airlines
Deal found 3/25$168
This Southwest deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/159:05 amPHX - DEN
1 stop4h 10mSouthwest
Sat 5/1710:55 amDEN - PHX
Nonstop1h 55mSouthwest
Deal found 3/25$182
This CheapOair deal was found by Cheapflights users on 3/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/175:50 amPHX - DEN
Nonstop1h 56mMultiple Airlines
Mon 5/264:00 pmDEN - PHX
1 stop18h 00mMultiple Airlines
Deal found 3/24$192
This Delta deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/2410:00 amPHX - DEN
1 stop3h 45mDelta
Tue 5/276:25 pmDEN - PHX
1 stop6h 23mDelta
Deal found 3/25$197
This United Airlines deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/251:35 pmPHX - DEN
Nonstop1h 54mUnited Airlines
Fri 7/259:04 pmDEN - PHX
Nonstop1h 56mUnited Airlines
Deal found 3/25$297
This FlightHub deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1110:10 amPHX - DEN
1 stop3h 55mContour
Sun 7/135:40 pmDEN - PHX
1 stop18h 05mContour
Deal found 3/25$298
This Alaska Airlines deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/269:00 amPHX - DEN
2 stops13h 59mAlaska Airlines
Mon 4/288:20 amDEN - PHX
1 stop26h 17mAlaska Airlines
Deal found 3/25$319

Cheapflights Fare Finder

Customize your flight search to find flights from Sky Harbor Intl to Boulder that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 26, 2025.
Use the filters below to find and compare flights from Phoenix Sky Harbor Intl Airport to Boulder that are best for you.

Fly from

Sky Harbor Intl

Fly to

Boulder

Route

Depart

Return

Price

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Wed 4/16

11:08 am-2:04 pm

Nonstop1h 56m

Denver Intl

Tue 4/29

5:40 pm-6:40 pm

Nonstop2h 00m

$107

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Tue 4/22

8:34 am-11:30 am

Nonstop1h 56m

Denver Intl

Tue 4/29

8:09 am-9:30 am

Nonstop2h 21m

$168

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Thu 5/15

3:35 pm-8:45 pm

1 stop4h 10m

Denver Intl

Tue 5/20

8:00 am-8:55 am

Nonstop1h 55m

$182

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Sat 5/17

5:50 am-8:46 am

Nonstop1h 56m

Denver Intl

Mon 5/26

4:00 pm-9:00 am

1 stop18h 00m

$192

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Sat 5/24

10:00 am-2:45 pm

1 stop3h 45m

Denver Intl

Tue 5/27

6:25 pm-11:48 pm

1 stop6h 23m

$197

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Sun 5/25

6:00 am-8:50 am

Nonstop1h 50m

Denver Intl

Wed 5/28

3:45 pm-8:39 pm

1 stop5h 54m

$257

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Fri 7/11

10:10 am-3:05 pm

1 stop3h 55m

Denver Intl

Sun 7/13

5:40 pm-10:45 am

1 stop18h 05m

$298

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Sat 4/26

9:00 am-11:59 pm

2 stops13h 59m

Denver Intl

Mon 4/28

8:20 am-9:37 am

1 stop26h 17m

$319

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Sat 4/26

7:35 pm-10:28 pm

Nonstop1h 53m

$58

PhoenixDenver

PHX - DEN

PHXDEN

Phoenix Sky Harbor Intl

Fri 4/25

8:43 am-11:42 am

Nonstop1h 59m

$94

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/25

Showing 1-10 of 18 results
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Best time to book a flight from Sky Harbor Intl to Boulder

Have a flexible travel schedule? Discover the best time to fly to Boulder from Sky Harbor Intl with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Phoenix Sky Harbor Intl Airport to Boulder

How far ahead should I book a flight from Phoenix Sky Harbor Intl Airport to Boulder?

Use this chart to determine the optimal time to book a round-trip flight from Sky Harbor Intl to Boulder. Price data was last updated on March 21, 2025.

To ensure you get the cheapest price possible for a flight from Phoenix Sky Harbor Intl Airport to Boulder, you should look to book at least 62 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Phoenix Sky Harbor Intl Airport to Boulder?

Currently, October is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to Boulder (average of $197). Flying from Phoenix Sky Harbor Intl Airport to Boulder in March is currently the most expensive (average of $278). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from PHX to BD9?

Find hourly flight availability from Sky Harbor Intl to Boulder. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 26, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Phoenix Sky Harbor Intl Airport to Boulder as you normally would.

What is the cheapest day to fly from Phoenix Sky Harbor Intl Airport to Boulder?

Use this chart to determine the cheapest time to fly round-trip from Sky Harbor Intl to Boulder. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Phoenix Sky Harbor Intl Airport to Boulder flight should consider departing on Wednesday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Phoenix Sky Harbor Intl Airport to Boulder

Explore weekly flight availability from Sky Harbor Intl to Boulder. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated March 26, 2025.

The most flights from PHX to BD9 are scheduled on a Monday (46 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (2 on average).

Rainfall in Boulder by month

Plan your trip to Boulder by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Boulder ranges from 0.5 - 2.3 inches per month. May is typically the wettest month, when rainfall can reach 2.3 in. January is typically the driest time to visit Boulder when rainfall is around 0.5 in.

Temperature in Boulder by month

Plan your trip to Boulder by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Boulder, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

Reviews of airlines servicing Boulder

Get insights into the airlines that provide service to Boulder. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Boulder. Reviews last updated March 26, 2025.
Read through reviews of airlines operating flights from Phoenix to Boulder, such as Southwest, Alaska Airlines and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.
Southwest
8.1
Very good
4,273 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.
Alaska Airlines
8.0
Very good
9,792 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.
Delta
8.0
Very good
7,891 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.
United Airlines
7.4
Good
8,608 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,273 reviews

Boarding

8.2

Overall

8.1

Food

7.1

Comfort

8.1

Entertainment

7.6

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Steven,Feb 2025

BZN - DEN

Bozeman Airport knows how to deal with snow. I saw many airlines leave with only small delays due to the foot of snow. Our plane was 4 hours delayed. I missed my connection in Denver with a 3.5 hour layover. Because of that, the best you Southwest could do was make me wait more hours, them send me to Chicago Midway, where I had to wait overnight, for 7 more hours until a flight to RSW was available. Nobody at Southwest told me that Midway shuts down after 8pm. Everything was closed. I had no idea. You just dumped me there. I am a 65 year old man and you dumped me in Midway without even a couch to lie on. I was awake 21 hours because of this. No, it was not an act of God. Other airlines were moving passengers out. It was incompetence Shame on you.

Related info for your journey

Find useful and relevant information for your journey from Sky Harbor Intl to Boulder. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What are the cheapest airlines to fly from Phoenix Sky Harbor Intl Airport to Boulder one-way?

    The cheapest airlines for a one-way flight from Phoenix Sky Harbor Intl Airport to Boulder are Frontier ($58), American Airlines ($94), and Delta ($99).

  • What are the most reliable airlines from Phoenix Sky Harbor Intl Airport to Boulder?

    Consider Air Canada (90%), Lufthansa (90%) or United Airlines (90%) when booking your flight. These represent the most reliable airlines when flying from Phoenix Sky Harbor Intl Airport to Boulder.

  • What are the cheapest flights from Phoenix Sky Harbor Intl Airport to Boulder?

    Looking at all options, your cheapest flight can be booked for $48. While the most popular route (Phoenix Sky Harbor Intl - Denver Intl) can be booked for $127 on average our data indicates $1,762 when flying from Phoenix Sky Harbor Intl Airport to Boulder.

  • Can I find deals for flights from Sky Harbor Intl to Boulder that include hotel bookings?

    Yes. In addition to deals on Sky Harbor Intl to Boulder flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Sky Harbor Intl to Boulder?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Sky Harbor Intl to Boulder.

  • Can I find deals for business class flights from Sky Harbor Intl to Boulder?

    Yes. Cheapflights offers flight deals from Sky Harbor Intl to Boulder by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Phoenix Sky Harbor Intl Airport to Boulder?

    Currently, October is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to Boulder (average of $197). Flying from Phoenix Sky Harbor Intl Airport to Boulder in March is currently the most expensive (average of $278). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Top 5 airlines flying from Sky Harbor Intl to Boulder

Discover the top 5 airlines that operate flights from Sky Harbor Intl to Boulder. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$48Average$106FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$126Average$251FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$137Average$269FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$137Average$351FlexibilityNo cancel feeOn-time69%
DeltaCheapest$172Average$258FlexibilityNo cancel feeOn-timeN/A
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