$66 Find Cheap Flights from Portland to Boulder

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Portland to Boulder departing on 6/3. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult

KAYAK searches hundreds of travel sites at once for deals on flights from Portland to Boulder

Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 22% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Free to useThere are no hidden charges or fees.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flights Deals
Useful Info
Flights Deals

Cheap Flight Deals from Portland to Boulder (PDX-DEN)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Portland to Boulder that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Recent round-trip flight deals from Portland to Boulder

KAYAK's recommended round-trip deals from the most popular airlines that fly from Portland to Boulder.
Discover the best prices for you by selecting your travel dates on KAYAK.
Frontier Logo
6:35 am - 10:12 amPDX-DEN
2h 37mnonstop
Frontier Logo
10:29 pm - 12:19 amDEN-PDX
2h 50mnonstop
$129Frontier
Find Deal
Wed, Jun 4 - Sat, Jun 7
Frontier Logo
6:37 am - 10:15 amPDX-DEN
2h 38mnonstop
Frontier Logo
9:20 pm - 11:04 pmDEN-PDX
2h 44mnonstop
$132Frontier
Find Deal
Wed, May 21 - Tue, May 27
United Airlines Logo
5:00 am - 8:34 amPDX-DEN
2h 34mnonstop
United Airlines Logo
4:00 pm - 8:47 pmDEN-PDX
5h 47m1 stop
$187United Airlines
Find Deal
Sat, May 31 - Sat, Jun 7
Southwest Logo
7:10 pm - 10:35 pmPDX-DEN
2h 25mnonstop
Southwest Logo
7:55 pm - 12:15 amDEN-PDX
5h 20m1 stop
$197Southwest
Find Deal
Wed, Jun 11 - Mon, Jun 16
Southwest Logo
12:20 pm - 8:45 pmPDX-DEN
7h 25m2 stops
Southwest Logo
12:35 pm - 2:10 pmDEN-PDX
2h 35mnonstop
$202Southwest
Find Deal
Thu, May 29 - Tue, Jun 3
Hawaiian Airlines Logo
5:30 pm - 12:05 amPDX-DEN
5h 35m1 stop
Hawaiian Airlines Logo
6:00 am - 12:18 pmDEN-PDX
7h 18m1 stop
$206Hawaiian Airlines
Find Deal
Fri, May 30 - Tue, Jun 3
Hawaiian Airlines Logo
7:00 am - 10:40 amPDX-DEN
2h 40mnonstop
Hawaiian Airlines Logo
6:00 am - 10:53 amDEN-PDX
5h 53m1 stop
$207Hawaiian Airlines
Find Deal
Sun, Jun 1 - Sun, Jun 8
Alaska Airlines Logo
5:35 pm - 11:59 pmPDX-DEN
5h 24m1 stop
Alaska Airlines Logo
7:06 pm - 8:50 pmDEN-PDX
2h 44mnonstop
$236Alaska Airlines
Find Deal
Tue, Jul 1 - Tue, Jul 8
Alaska Airlines Logo
10:30 am - 12:05 amPDX-DEN
12h 35m2 stops
Alaska Airlines Logo
6:00 am - 12:18 pmDEN-PDX
7h 18m1 stop
$265Alaska Airlines
Find Deal
Wed, Jun 4 - Sat, Jun 7
United Airlines Logo
10:00 am - 5:11 pmPDX-DEN
6h 11m1 stop
United Airlines Logo
8:00 pm - 12:31 amDEN-PDX
5h 31m1 stop
$351United Airlines
Find Deal
Wed, May 14 - Sun, May 18
Useful Info

Good to know

Low seasonFebruary
High seasonJune
Cheapest flight$66
Best time to beat the crowds with an average 6% drop in price.
Most popular time to fly with an average 4% increase in price.
Flight from Portland to Denver

When to book flights from Portland to Boulder

Are your dates flexible? Find out the best times to travel from Portland to Boulder based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from Portland to Boulder

  • Which airports will I be using when flying from Portland to Boulder?

    When flying out of Portland you’ll be using Portland. Boulder does not have its own airport so you’ll be flying into nearby Denver Intl airport, which is 33.4 mi away.

  • How long does a flight from Portland to Boulder take?

    Direct flights cover the 989 miles separating Portland and Boulder in about 2h 25m.

  • How many flights are there between Portland and Boulder?

    25 direct flights run between Portland and Boulder on a daily basis. On average, there are about 176 departures each week.

  • What’s the cheapest day of the week to fly between Portland and Boulder?

    Consider leaving on a Wednesday and avoid Saturdays if you are looking for the best rates. For your return to Portland, you’ll find the best rates on Tuesdays and the most expensive ones on Fridays.

  • How does KAYAK find such low prices on flights from Portland to Boulder?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Portland to Boulder.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Portland to Boulder?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Boulder from Portland is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Portland to Boulder?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Boulder with an airline and back to Portland with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Portland to Boulder?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Boulder from Portland up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Portland to Boulder?

    In the last 72 hours, the cheapest one-way ticket between Portland and Boulder found on KAYAK was with Frontier for $66. Frontier offered a round-trip connection from $129 and United Airlines from $187.

Top tips for finding cheap flights from Portland to Boulder

  • There is no airport in Boulder. Instead, you’ll be flying into Denver Airport when flying between Portland and Boulder.
  • The cheapest flight from Portland to Boulder was found 30 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be February, March and April. The cheapest month to fly is September.

Top 5 airlines serving Portland to Boulder

Need help choosing which airline to fly with from Portland to Boulder? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Alaska AirlinesOverall score based on 9985 reviews
8.5Crew
8.1Boarding
7.1Food
7.1Entertainment
7.9Comfort
Airline reviews

The actual flight I was rescheduled onto was from Seattle to Bozeman. The flight itself was fine, but due to delays/air traffic issues i spent the day hanging out at the Seattle airport and had to miss a day of work.

4.0 OkayAnonymous, May 2025PDX - BZN
Read more Alaska Airlines reviews

The actual flight I was rescheduled onto was from Seattle to Bozeman. The flight itself was fine, but due to delays/air traffic issues i spent the day hanging out at the Seattle airport and had to miss a day of work.

OUr pilot was very good and also a good landing in a very gusting Phoenix. Most important.

It was alright other than the changes in the Alaska Lounge. That and the migraine I had were disappointing. Other then that everything went well.

It was a short flight so no refreshments or entertainment which was fine.

Flying in both directions across country the gate designated on my boarding pass was wrong. From w to e across the country the passenger next to me coughed the entire way.

Although both planes (flights) had mechanical issue delaying both of my flights, the crew members handled everything with ease. Both flights had the smoothest take off and landing. I opted to upgrade my seat to first class and really lucked out getting the seat at the very front of the plane. Awesome treat to myself. I really enjoyed my flight.

The staff from check-in counter to the flight crew were great. Flight was right on schedule. 10/10

Changed flight from San Fran to Seattle Then with a Delayed takeoff barely made my connection Waited over an hour for luggage 😜

It was good. There was a mistake made in Seattle. Somehow we were bumped out of our seats as if we weren't on the flight anymore. The woman at the gate caught it and announced our name to come up and she fixed it.

I wouldn’t fly with Alaska again if you paid me.

Bring back peanuts Take our drink orders when were all seated, especially after you switch to assigned seating.

Staff was far less than helpful at all times. Departure and arrival times mean nothing to Southwest. Extremely disappointed, will never fly with them again, and I’ll be sure to share my experience with all.

It is southwest seat was ok. Not the most comfortable seat

I’ve always loved Southwest. No issues at all. I was flying standby and the gate agent was extremely friendly and helpful. Boarding was smooth and I was able to get a window seat in the emergency exit row. Crew was fantastic! They were very professional and accommodating. We had to divert from our destination due to weather but the flight crew kept everyone at ease and informed us of all pertinent information. Excellent flight

The price of the tickets isn't matching the flight experience. No matter how long the flight is, you're only getting pretzels. The flight attendants looked unkept and over it.

Plz don't take away free bags and free seating

The seats were a bit cramped and worn, but otherwise okay.

I would have liked to arrive on time - not 5 hours late!

After a 3 hour layover in Denver my flight was delayed over 5 hours! No explanation; no assistance; no offer to provide compensation; no one at Southwest was willing to offer any assistance. 8 hours in the Denver airport - ridiculous!

It was a perfect flight in all aspects! Both legs!

Alaska airlines was great, Kayak not so great. I couldn’t get my boarding passes and I was last to board. Will not use Kayak again, ever!

Love that as soon as you get on you are seeing and hearing Hawaii. Was glad to hear that they are stressing safety over the pressure to arrive on time.

Despite two calls as well as a chat on the website, Alaska would not add my TSA number to my reservation. The flight was switched from Hawaiian to Alaska which caused them to mess this up in the first place

The departure gate was changed from C1 to B18 but it was never announced at the C1 gate nor did I receive any email or text message or phone call about the gate change. I was in a window seat. In the other two seats next to me were Mr. Rotund and Ms. Rotunda, a youngish couple. Just the two of them should have booked three seats. I was smashed up against the wall and window for five hours. Overall, I'd say my flight sucked. Wouldn't you?

I couldn't get checked in 24 hours before either leg of my flight. I tried both my Alaska and Hawaiian codes on both apps.

We moved from the international terminal to a new location. I think there are still some bugs to work out . We didn’t receive check in notification and had to scramble to find it but i think it will work out

I'm was impressed with their service. Everything was great

All in All a great experience. Cost of luggage sucks … first time I ever had to pay for luggage. Otherwise the check in counter was awesome, the gate clerks were great and the Stewards & Esses were the best.

As my daughter was boarding the flight they pulled her from the line and told her, after she had checked in and checked a bag, that she could not board the flight due to a fraud flag on the debit card used for the ticket purchase. The personnel would not allow me to speak to them, saying I had to take it up with customer service that was not present. They tried to get my daughter to purchase another ticket on the spot or get out. The customer service personnel were insistant that the personnel at the gate be on the phone which they would not allow. Would not accept payment from three different accounts and did not resolve the issue. Many conflicting reports about the source of the problem, the fraud department is uncontactable. The only good thing to come of it was checked bag arrived. Our family will not be using Hawaiian Airlines. Ever.

Great staffing. Terrible food. Please do cold sandwiches or salads. the "hot pickets" are terrible.

The gate attendant let me walk right by her with a bag too big for the overhead compartment

Food choices were very limited. Taste of the dishes was average.

I liked all the informational texts. I always knew where to go and when .

Received an email the night before showing that there would be seatback entertainment on our flight. We get on and there was no seatback entertainment. And then it was a scramble to try to set up the iPads for the kids before takeoff so they could watch something for the four hour flight.

The reason I don’t fly United. No in seat entertainment for a long flight and inconsistent WiFi and entertainment available from my device.

It was a good flight. Nothing comes to mind about how it could have been better. It was a newer plane, seemed like a great upgrade from your older ones. Staff was very good as well.

The food for long haul was poor compared to Singapore airlines economy. Pasta plain with tomato sauce . Singapore airlines give me Hagen dash small ice cream cup it was great. The choices of dinner course Singapore air also much better The crew mostly friendly. The economy seat are as expected.

The plane was clean. The staff was excellent. The flight attendants were very good. Enjoyable flight. Overall. The seats in the back are too small but, will always be.

Flight was 3 1/2 hour delayed with no credit or meal vouchers

late departure due to some unspecified issue with ventilating the cabin. They got it running but it was FREEZING for the whole flight. I asked for a blanket but they didn't provide one. They could not turn up the heat. it was quite miserable.

The seats were hard molded plastic covered in plastic vinyl. And the scam to charge people extra to sit together. Don’t they know we can just ask someone to trade seats. And watching the staff separate young children from parents… super classy. We had to guilt them into offering up our seats. This companies policies suck. Don’t give them your money.

Seats are uncomfortable but price is good. Guess I can put up with misery for four hours.

The plane failed preflight inspection, so we sat there for 90 mins while they tried to fix it. Ultimately, everything was remedied and we made our connecting flight; instead of a 2 hour layover at the airport, we spent it waiting on the plane.

I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.

The seats were extremely hard and uncomfortable. It was disappointing even for a budget airline.

Delayed each time on a round trip with no significant weather interference. Updates to flight times came after the fact. 30 min behind in boarding and board and phone still show an on time departure. Some mysterious extra 300 miles that came so surprising they had to fuel while we were already on board?

Our flight was canceled for no known reason. We weren’t told until we were checking in at 5:00 am. This was after our last flight with Frontier where we sat on the plane for three hours (not an exaggeration) before we took off because of a mechanical issue. We won’t be flying Frontier again.

Allowed me to chose my seat without extra charge (I purchased full-price ticket) and boarding was in group1. Didn't even serve water.

Canceled original flight and wasn't clear on rebooked flight. Had to pay for bags which was more than the flight itself. Normal help, drinks etc. you have to pay for. This is Not a low cost airline.

Stuck in Phoenix for two days, not even a hotel voucher offered.

Everything you need to know for your flight from Portland to Boulder

Complete your trip to Boulder with a hotel stay or car rental

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.