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$64+ 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 11/17. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — DEN
Aug 24 — Aug 311
Sun 8/24
Sun 8/31
1 adult, Economy
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Cheapflights Tip: The best prices from Portland to Boulder are usually found in September or October, booked 30 days in advance, depart on a Friday or Saturday and return on a Tuesday

Cheap flight deals from Portland to Boulder

Keep the following information in mind while searching for Portland to Boulder flight deals. Data was last updated August 19, 2025.

Round-trip from

$95
(Cheapflightsfares)

One-way from

$64
(Cheapflightsfares)

Popular in

March

Cheapest in

September

Average price

$178
From Portland to Boulder
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One-way flight from Portland to Boulder
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Highest demand for flights based on searches. 5% potential increase in price ($11 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find 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 August 19, 2025.

This Justfly.com deal was found by Cheapflights users on 8/19. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/216:05 amPDX - DEN
Nonstop2h 39mFrontier
Wed 9/248:50 pmDEN - PDX
Nonstop2h 44mFrontier
Deal found 8/19$94
This Cheapflightsfares deal was found by Cheapflights users on 8/19. 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.
Fri 9/56:05 amPDX - DEN
Nonstop2h 39mFrontier
Mon 9/810:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/19$95
This Cheapflightsfares deal was found by Cheapflights users on 8/17. 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.
Thu 9/186:05 amPDX - DEN
Nonstop2h 39mFrontier
Sun 9/2110:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/17$96
This Frontier deal was found by Cheapflights users on 8/17. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/256:05 amPDX - DEN
Nonstop2h 39mFrontier
Thu 10/210:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/17$97
This Cheapflightsfares deal was found by Cheapflights users on 8/17. 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.
Fri 9/56:05 amPDX - DEN
Nonstop2h 39mFrontier
Wed 9/108:50 pmDEN - PDX
Nonstop2h 44mFrontier
Deal found 8/17$98
This Frontier deal was found by Cheapflights users on 8/17. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/247:15 amPDX - DEN
Nonstop2h 43mFrontier
Fri 10/310:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/17$99
This Cheapflightsfares deal was found by Cheapflights users on 8/17. 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 9/107:15 amPDX - DEN
Nonstop2h 43mFrontier
Sat 9/208:50 pmDEN - PDX
Nonstop2h 44mFrontier
Deal found 8/17$100
This Frontier deal was found by Cheapflights users on 8/17. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/247:15 amPDX - DEN
Nonstop2h 43mFrontier
Sat 9/278:50 pmDEN - PDX
Nonstop2h 44mFrontier
Deal found 8/17$101
This Cheapflightsfares deal was found by Cheapflights users on 8/17. 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.
Sun 8/316:27 amPDX - DEN
Nonstop2h 39mFrontier
Fri 9/510:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/17$102
This Kiwi.com deal was found by Cheapflights users on 8/17. 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.
Sun 8/316:27 amPDX - DEN
Nonstop2h 39mFrontier
Sun 9/710:29 pmDEN - PDX
Nonstop2h 43mFrontier
Deal found 8/17$103
This Cheapflightsfares deal was found by Cheapflights users on 8/18. 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.
Sat 10/1112:43 pmPDX - DEN
Nonstop2h 43mFrontier
Fri 10/179:58 amDEN - PDX
Nonstop2h 50mFrontier
Deal found 8/18$104
This Frontier deal was found by Cheapflights users on 8/18. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/86:05 amPDX - DEN
Nonstop2h 39mFrontier
Tue 9/98:50 pmDEN - PDX
Nonstop2h 44mFrontier
Deal found 8/18$105

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 August 19, 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

Sun 9/21

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Wed 9/24

8:50 pm-10:34 pm

Nonstop2h 44m

$94

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 9/25

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Mon 9/29

10:29 pm-12:12 am

Nonstop2h 43m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 11/13

12:52 pm-4:35 pm

Nonstop2h 43m

Denver Intl

Fri 11/14

10:05 am-11:56 am

Nonstop2h 51m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 9/19

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Mon 9/22

10:29 pm-12:12 am

Nonstop2h 43m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 9/5

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Mon 9/8

10:29 pm-12:12 am

Nonstop2h 43m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 9/5

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Sun 9/7

10:29 pm-12:12 am

Nonstop2h 43m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 9/18

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Sun 9/21

10:29 pm-12:12 am

Nonstop2h 43m

$95

PortlandDenver

PDX - DEN

PDXDEN

Portland

Sun 9/14

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Sun 9/21

10:29 pm-12:12 am

Nonstop2h 43m

$96

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 10/3

6:05 am-9:44 am

Nonstop2h 39m

Denver Intl

Sun 10/5

10:29 pm-12:12 am

Nonstop2h 43m

$96

PortlandDenver

PDX - DEN

PDXDEN

Portland

Sun 12/7

3:14 pm-6:48 pm

Nonstop2h 34m

$69

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/17

Showing 1-10 of 19 results
1
2

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 August 8, 2025.

To ensure you get the cheapest price possible for a flight from Portland to Boulder, you should look to book at least 30 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, October is the cheapest month in which you can book a flight from Portland to Boulder (average of $197). Flying from Portland 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 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 August 19, 2025.

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

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 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 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 August 19, 2025.

The most flights from PDX to BD9 are scheduled on a Monday (23 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (1 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 August 19, 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
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Southwest
8.0
Very good
4,246 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Hawaiian Airlines
7.8
Good
2,665 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
United Airlines
7.4
Good
8,922 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Frontier
5.8
Fair
3,211 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Boarding

8.1

Comfort

7.8

Food

7.1

Overall

8.0

Entertainment

7.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

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 9 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, 212 users have taken a look at flights from Portland to Boulder.

  • How long is the flight from Portland to Boulder?

    Airlines like Frontier fly from Portland to Boulder in about 2h 39m. 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 most reliable airlines from Portland to Boulder?

    Consider United Airlines (84%), Lufthansa (84%) or SWISS (83%) 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 $697, our data indicates the cheapest price to be $88. The most popular route (Portland - Denver Intl), is priced around $99.

  • 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, October is the cheapest month in which you can book a flight from Portland to Boulder (average of $197). Flying from Portland 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

Browse thousands of different options on Cheapflights for your next trip

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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 August 19, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$56Average$137FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$231FlexibilityNo cancel feeOn-time85%
SouthwestCheapest$157Average$309FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$157Average$372FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$165Average$264FlexibilityNo cancel feeOn-time75%
DeltaCheapest$198Average$256FlexibilityNo cancel feeOn-timeN/A

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