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$43+ Cheap flights from Portland (PDX) 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 1/3. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — DEN
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
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Cheapflights Tip: The best prices from Portland to Boulder are usually found in January or August, booked 29 days in advance, depart on a Friday or Thursday and return on a Saturday

Cheap flight deals from Portland to Boulder

Cheapest flights from Portland to Boulder
Explore the most affordable flight options available from Portland to Boulder. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 12, 2025.

This CheapOair deal was found by Cheapflights users on 12/9. 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.
Thu 12/182:29 pmPDX - DEN
1 stop12h 29mFrontier
Sun 1/189:05 amDEN - PDX
Nonstop2h 59mFrontier
Deal found 12/9$162
This Expedia deal was found by Cheapflights users on 12/9. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3012:47 pmPDX - DEN
Nonstop2h 28mMultiple Airlines
Tue 1/611:31 amDEN - PDX
Nonstop3h 02mMultiple Airlines
Deal found 12/9$168
This Expedia deal was found by Cheapflights users on 12/9. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3012:47 pmPDX - DEN
Nonstop2h 28mMultiple Airlines
Mon 1/57:11 pmDEN - PDX
Nonstop2h 59mMultiple Airlines
Deal found 12/9$173
This Alaska Airlines deal was found by Cheapflights users on 12/9. 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.
Tue 12/305:50 pmPDX - DEN
Nonstop2h 38mAlaska Airlines
Tue 1/611:31 amDEN - PDX
Nonstop3h 02mAlaska Airlines
Deal found 12/9$187
This Kiwi.com deal was found by Cheapflights users on 12/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/298:45 pmPDX - DEN
1 stop11h 10mMultiple Airlines
Mon 1/57:20 amDEN - PDX
Nonstop2h 58mMultiple Airlines
Deal found 12/9$190
This United Airlines deal was found by Cheapflights users on 12/10. 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.
Wed 12/315:00 amPDX - DEN
Nonstop2h 32mUnited Airlines
Fri 1/28:00 amDEN - PDX
Nonstop3h 01mUnited Airlines
Deal found 12/10$213
This Expedia deal was found by Cheapflights users on 12/8. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/182:29 pmPDX - DEN
1 stop8h 04mMultiple Airlines
Wed 1/77:00 amDEN - PDX
1 stop6h 38mMultiple Airlines
Deal found 12/8$215

Find flight deals from Portland to Boulder

Keep the following information in mind while searching for Portland to Boulder flight deals. Data was last updated December 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$97
(Super.com)

One-way from

$43
(Mytrip)

Popular in

December

Cheapest in

January

Average price

$249
Provider with most accurate pricing for Portland-Denver Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-Denver Intl flights.
Search Deals
From Portland to Boulder
Search Deals
One-way flight from Portland to Boulder
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($6 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland 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 December 12, 2025.
Use the filters below to find and compare flights from Portland to Boulder that are best for you.

Fly from

Portland

Fly to

Boulder

Route

Depart

Return

Price

PortlandDenver

PDX - DEN

PDXDEN

Portland

Tue 2/10

7:21 am-10:53 am

Nonstop2h 32m

Denver Intl

Tue 2/17

11:38 am-1:38 pm

Nonstop3h 00m

$137

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 1/14

6:20 am-9:45 am

Nonstop2h 25m

Denver Intl

Sat 1/17

8:00 am-10:00 am

Nonstop3h 00m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 2/19

4:00 pm-7:33 pm

Nonstop2h 33m

Denver Intl

Tue 3/3

11:50 am-1:44 pm

Nonstop2h 54m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 2/11

5:35 pm-11:35 pm

1 stop5h 00m

Denver Intl

Tue 2/17

11:38 am-1:38 pm

Nonstop3h 00m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 2/11

6:20 am-9:45 am

Nonstop2h 25m

Denver Intl

Fri 2/13

10:00 pm-12:05 am

Nonstop3h 05m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 1/2

7:00 am-10:35 am

Nonstop2h 35m

Denver Intl

Tue 1/6

11:31 am-1:33 pm

Nonstop3h 02m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Sun 2/15

7:05 am-10:42 am

Nonstop2h 37m

Denver Intl

Wed 2/18

11:38 am-1:38 pm

Nonstop3h 00m

$147

PortlandDenver

PDX - DEN

PDXDEN

Portland

Sat 1/10

9:20 am-5:34 pm

1 stop7h 14m

Denver Intl

Sat 1/17

7:00 am-12:32 pm

1 stop6h 32m

$157

PortlandDenver

PDX - DEN

PDXDEN

Portland

Tue 1/13

5:50 am-11:54 am

1 stop5h 04m

Denver Intl

Tue 1/13

4:10 pm-10:54 pm

1 stop7h 44m

$157

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 2/18

7:05 am-10:42 am

Nonstop2h 37m

Denver Intl

Thu 2/19

1:10 pm-8:50 pm

1 stop8h 40m

$157

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/11

Showing 1-10 of 21 results
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Best time to book a flight from Portland to Boulder

Have a flexible travel schedule? Discover the best time to fly to Boulder from Portland 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 Portland to Boulder

How far ahead should I book a flight from Portland to Boulder?

Use this chart to determine the optimal time to book a round-trip flight from Portland to Boulder. Price data was last updated on December 5, 2025.

To ensure you get the cheapest price possible for a flight from Portland to Boulder, you should look to book at least 29 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 Portland to Boulder?

Currently, February is the cheapest month in which you can book a flight from Portland to Boulder (average of $37). Flying from Portland to Boulder in July is currently the most expensive (average of $98). 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 PDX to BD9?

Find hourly flight availability from Portland 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 December 12, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 45% on flights from Portland to Boulder by exploring options for tickets in the morning.

What is the cheapest day to fly from Portland to Boulder?

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

Travelers seeking maximum savings on their Portland to Boulder flight should consider departing on Friday mornings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Portland to Boulder

Explore weekly flight availability from Portland 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 December 12, 2025.

The most flights from PDX to BD9 are scheduled on a Thursday (19 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (6 on average).

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 December 12, 2025.
Read through reviews of airlines operating flights from Portland to Boulder, such as Alaska Airlines, Southwest, and Hawaiian Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Alaska Airlines
8.0
Very good
11,431 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Southwest
7.9
Good
4,253 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Hawaiian Airlines
7.8
Good
2,817 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
United Airlines
7.4
Good
9,095 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Frontier
5.8
Fair
3,084 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Entertainment

7.0

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.

Related info for your journey

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

  • What airport do you fly from for flights from Portland to Boulder?

    Most people fly from Portland (PDX) if they book a flight from Portland to Boulder. On average, Portland has 11 outbound flights to Boulder per day from 6 airlines. Portland is conveniently located just 6.0 mi from Portland’s city center.

  • How popular is this Portland to Boulder flight route?

    Within the past month, 208 users have taken a look at flights from Portland to Boulder.

  • How long is the flight from Portland to Boulder?

    Airlines like Alaska Airlines and Southwest fly from Portland to Boulder in about 2h 25m. The time it takes to get you to your destination is usually consistent. Portland and Boulder are separated by a distance of 989 mi. Most flights are nonstop.

  • What are the cheapest airlines to fly from Portland to Boulder one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $36. Delta flights start at $74 while deals on Alaska Airlines start at $78 one-way.

  • What are the most reliable airlines from Portland to Boulder?

    Consider Lufthansa (97%), United Airlines (96%) or Frontier (90%) when booking your flight. These represent the most reliable airlines when flying from Portland to Boulder.

  • What are the cheapest flights from Portland to Boulder?

    Looking for the cheapest flight from Portland to Boulder? While on average our users pay $757, our data indicates the cheapest price to be $72. The most popular route (Portland - Denver Intl), is priced around $98.

  • Can I find deals for flights from Portland to Boulder that include hotel bookings?

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

  • How can I find direct flights from Portland to Boulder?

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

  • Can I find deals for business class flights from Portland to Boulder?

    Yes. Cheapflights offers flight deals from Portland 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 Portland to Boulder?

    Currently, February is the cheapest month in which you can book a flight from Portland to Boulder (average of $37). Flying from Portland to Boulder in July is currently the most expensive (average of $98). 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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Alternative routes for Portland to Boulder

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Portland to Boulder

Discover the top 6 airlines that operate flights from Portland 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 December 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$58Average$149FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$234FlexibilityNo cancel feeOn-time85%
DeltaCheapest$128Average$247FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$157Average$265FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$157Average$312FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$157Average$369FlexibilityNo cancel feeOn-time69%

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