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$38+ 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 5/14. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — DEN
Feb 25 — Mar 41
Tue 2/25
Tue 3/4
1 adult, Economy
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The best prices from Portland to Boulder are usually found in September or October, booked 83 days in advance, depart on a Friday or Thursday and return on a Saturday

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 February 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$57
(Cheapflightsfares)

One-way from

$38
(Cheapflightsfares)

Popular in

December

Cheapest in

September

Average price

$157
Provider with most accurate pricing for Portland-Denver Intl flight deals.
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Provider most trusted by Cheapflights users for Portland-Denver Intl flights.
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From Portland to Boulder
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One-way flight from Portland to Boulder
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($15 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in February 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 February 20, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 2/19. 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.
Tue 3/46:32 amPDX - DEN
Nonstop2h 41mFrontier
Sat 3/1510:45 pmDEN - PDX
Nonstop2h 52mFrontier
Deal found 2/19$57
This Trip.com deal was found by Cheapflights users on 2/19. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/1210:06 amPDX - DEN
Nonstop2h 34mMultiple Airlines
Wed 3/197:00 amDEN - PDX
1 stop4h 52mMultiple Airlines
Deal found 2/19$124
This Alaska Airlines deal was found by Cheapflights users on 2/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/187:15 amPDX - DEN
1 stop7h 57mAlaska Airlines
Tue 3/252:53 pmDEN - PDX
Nonstop2h 49mAlaska Airlines
Deal found 2/19$187
This United Airlines deal was found by Cheapflights users on 2/20. 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 5/74:20 pmPDX - DEN
Nonstop2h 36mUnited Airlines
Sun 5/117:45 amDEN - PDX
1 stop5h 54mUnited Airlines
Deal found 2/20$188
This Southwest deal was found by Cheapflights users on 2/19. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/1210:50 amPDX - DEN
2 stops7h 15mSouthwest
Wed 3/199:45 pmDEN - PDX
Nonstop2h 45mSouthwest
Deal found 2/19$192
This Delta deal was found by Cheapflights users on 2/20. 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.
Thu 4/35:10 pmPDX - DEN
1 stop5h 30mDelta
Sat 4/55:45 amDEN - PDX
1 stop4h 23mDelta
Deal found 2/20$197

Find flights from Portland to Boulder within your budget

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 February 20, 2025.

Fly from

Portland

Fly to

Boulder

Route

Depart

Return

Price

PortlandDenver

PDX - DEN

PDXDEN

Portland

Tue 3/4

6:32 am-10:13 am

Nonstop2h 41m

Denver Intl

Sat 3/15

10:45 pm-12:37 am

Nonstop2h 52m

$57

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 3/12

10:06 am-1:40 pm

Nonstop2h 34m

Denver Intl

Wed 3/19

7:00 am-10:52 am

1 stop4h 52m

$124

PortlandDenver

PDX - DEN

PDXDEN

Portland

Tue 3/18

7:15 am-4:12 pm

1 stop7h 57m

Denver Intl

Tue 3/25

2:53 pm-4:42 pm

Nonstop2h 49m

$187

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 5/7

4:20 pm-7:56 pm

Nonstop2h 36m

Denver Intl

Sun 5/11

7:45 am-12:39 pm

1 stop5h 54m

$188

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 3/12

10:50 am-7:05 pm

2 stops7h 15m

Denver Intl

Wed 3/19

9:45 pm-11:30 pm

Nonstop2h 45m

$192

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 4/3

5:10 pm-11:40 pm

1 stop5h 30m

Denver Intl

Sat 4/5

5:45 am-9:08 am

1 stop4h 23m

$197

PortlandDenver

PDX - DEN

PDXDEN

Portland

Wed 5/14

6:20 am-9:58 am

Nonstop2h 38m

$38

PortlandDenver

PDX - DEN

PDXDEN

Portland

Thu 5/15

7:19 pm-10:56 pm

Nonstop2h 37m

$89

PortlandDenver

PDX - DEN

PDXDEN

Portland

Fri 3/14

5:15 pm-11:49 pm

1 stop5h 34m

$98

PortlandDenver

PDX - DEN

PDXDEN

Portland

Sun 3/16

5:10 pm-11:48 pm

1 stop5h 38m

$99

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

Showing 1-10 of 14 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.

Travel insights for flights from Portland to Boulder

Get recent, data-driven insights about flights from Portland to Boulder including ideal travel times, pricing trends, and more.

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 February 14, 2025.

To ensure you get the cheapest price possible for a flight from Portland to Boulder, you should look to book at least 83 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 February 20, 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 June 2, 2024.

Travelers seeking maximum savings on their Portland 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 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 February 20, 2025.

The most flights from PDX to BD9 are scheduled on a Thursday (14 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (6 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 February 20, 2025.
See what other customers who have flown with Southwest, Alaska Airlines and Delta from Portland to Boulder have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Southwest
8.1
Very good
4,411 reviews
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Alaska Airlines
8.0
Very good
9,697 reviews
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Delta
8.0
Very good
8,219 reviews
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

United Airlines
7.4
Good
8,765 reviews
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,411 reviews

Food

7.1

Boarding

8.2

Comfort

8.1

Overall

8.1

Crew

8.7

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

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 10 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, 275 users have taken a look at flights from Portland to Boulder.

  • 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 $38. United Airlines flights start at $89 while deals on Alaska Airlines start at $98 one-way.

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

    Consider United Airlines (90%), Copa Airlines (88%) or Lufthansa (86%) 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 $798, our data indicates the cheapest price to be $50. The most popular route (Portland - Denver Intl), is priced around $115.

  • 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

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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 February 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$55Average$115FlexibilityNo cancel feeOn-time62%
Alaska AirlinesCheapest$128Average$257FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$148Average$390FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$151Average$321FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$166Average$276FlexibilityNo cancel feeOn-time71%
DeltaCheapest$196Average$326FlexibilityNo cancel feeOn-timeN/A
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