€312 Find cheap flights 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 to Boulder departing on 19/1. 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.
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Good to know

Low season

January

High season

June

Cheapest flight

€312
Best time to beat the crowds (11% less expensive on average)
Most popular time to fly (21% more expensive on average)
Flight from Dublin to Denver

FAQs - booking Boulder flights

  • How to fly to Boulder?

    You cannot fly directly to Boulder. KAYAK recommends you fly to Denver Intl (DEN) (53.76 km from Boulder). From there you can hire a car or take a taxi.

  • What airports are near Boulder?

    The closest airport is Denver Intl (DEN) (53.76 km). KAYAK recommends you fly to Denver Intl.

  • How far is Denver Intl Airport from central Denver?

    There are 30 km between Denver city centre and Denver Intl Airport.

  • What is the name of Denver’s airport?

    Denver is served by Denver Intl Airport, also commonly referred to as Denver or Denver Intl. The airport code is DEN.

  • How does KAYAK find such low prices on flights 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 to Boulder.

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

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

  • What is the Hacker Fare option on flights 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 with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight 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 up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top tips for finding cheap flights to Boulder

  • There is no major airport in Boulder. It is instead served by Denver Intl Airport.
  • Looking for cheap airfare to Boulder? 25% of our users found return tickets to Boulder for the following prices or less: From Dublin €3,224
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be June, July and August. The cheapest month to fly from Ireland is February.
  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Boulder flight deals.
See more tips

Top 4 airlines flying to Boulder

Need help choosing which airline to fly with from Ireland 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.
7.4
United AirlinesOverall score based on 9171 reviews
8.1Crew
6.7Food
7.1Entertainment
7.3Comfort
7.7Boarding
Airline reviews

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.

10.0 ExcellentJason, Nov 2024MSO - DEN
Read more United Airlines reviews

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.

I was at the back of the plane with earphones, and I could still hear the chatty flight attendants; I wasn't able to sleep at all.

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

United airlines was top for my last trip in every way

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.

Horrible; seating was atrocious - inadequate leg room and seat width tight even for a small individual. Profits shouldn’t be everything!

Liked that we left on time for each flight. Snacks not the best, but we're okay.

It was fine. The flight attendant appeared to be in a bad mood but everything was fine.

Never took flight. See previous comment on trip from Boston to Reykjavik. Used a different airline that i had to find and book.

One of the worst airlines I ever flew. Boarding is a disaster, they are always late, the planes are overly crowded. Everyone on my flight lost their connection because they were 2h late. Reykjavik is also not the best airport out there.

My only area of issue was the flight was rather warm and the knobs for cool air didn't allow much cool air to come through. Everything else was great.

Been travelling for 2mo. And when you meet flight Attendants that love their jobs you can just tell. And makes flying with them worth another flight in the future!!

Everything was great! My only critique is 25 euro for wifi is wild, but I get it

Good, but I feel there should be a separate boarding line for seniors

Easy check in and boarding. Staff pleasant and helpful. Will continue to fly with Iceland air. Aircraft clean

Plane left an hour late and missed our connecting flight. Your service center was closed ao Alaska Airlines could not change the ticket. Thus we missed the chance to get out that night to San Jose. This is a major operational blunder.

Well! They got me as far as Iceland, let me wait around at the airport since my next flight had either left or canceled, finally gave me my luggage, and sent me to wait quite some time with seven other people for a ride to a hotel. At the hotel we got a chef's salad, a nice room for the night which unfortunately had feather pillows and duvet (allergies), a really great and spectacular buffet for breakfast (small but stunning), taxis back to the airport for the 9:30 Delta flight back to Minneapolis. The Delta flight has free food and liquor included which Icelandair does not. All in all, it falls far short of my worst ever United flight to SGN. Icelandair did change my reservation after my roommate tested positive for COVID and we canceled our plans to travel around Iceland, but the charges were fairly hefty. I had trouble contact Kayak's agents to discuss changing my reservations and finally contacted Icelandair who changed them. (I used their contact form and put in several requests for call backs.) Of course, they called just after I made the change with Icelandair.

never seen an international flight , over 5 hours that had no food provided. we flew from iceland to vancouver, no food, no even a snack. For entertainment you had to buy the headphones which are normally also provided for free on any other airlines.

Friendly crew who apologised and explained reason for delay. Good on board service. Rather cramped seating. Late departure.

Very sad, couldn't stop crying. Was an hour delay in Ireland and when we got to Canada the flight was boarded and couldn't get on. Was the last flight of the day. Now in a hotel waiting on a stand by.I have to got o work, so I'll go first available while my son stays in the hotel til one's available

Was not aware that Aer Lingus was like the cut-rate services in the states, with no food or beverage (other then 3.50 Euro coffee) and no screens for entertainment. Was a great flight, but not much in the way of services.

Both flights late. Almost missed connecting flight and flight staff not willing to help expedite us off the plane.

during a very rough flight, I was forced to sit in a last row seat, fell asleep, and was forced to return to my assigned seat after the turbulence. The stewardess then used that seat to sleep.

I didn’t realize Aer Lingus was a “nickel and dime” kind of airline where you had to separately buy all the amenities you wanted. The push to purchase duty-free beauty products was off-putting. And our row had the least amount of leg room I’ve ever dealt with on a flight.

We couldn't talk to aer lingus we had issues with the flight change and aer lingus made us talk to kayak

Very pleasant staff, there was some turbulence but the captain was very apologetic and gave notice where possible.

Flight was great. Had to wait almost 100 minutes for luggage (some problem in the delivery). This may not be an Aer Lingus problem, but an SFO problem.

Loved it! Best airline to fly with. Nice crew, good planes, good food!

Flight was fine, food better than anticipated and flight attendants were helpful and friendly.

Our headphone plug is broken, we can not enjoy our entertainment, especially traveling with 5 year old who like to watch movie

It was good but I wished if they could have sign do not disturb if we did not wanted any meals . I was tired and slept through the entire flight and woke up just before landing .being hungry Too late to ask for something to eat before exiting the flight . Left feeling hunger 🙁

Pleasant, attentive and efficient flight attendants. Boarding process and seat selection easy. No internet on transatlantic flight. Extremely uncomfortable, rigid seat.

The seats of the Boeing 787-10 Dreamliner were ridiculously uncomfortable. I was on 10 flights during this vacation and this plane was super uncomfortable both times I was on one whereas all of the others were perfectly fine. Additionally, these planes do not have any air vents that passengers can control, the climate is entirely controlled by the crew which made for an extremely uncomfortable temperature for the duration. The flight attendants tried to make everyone happy with the temperature but several people you could tell were excessively warm and just wanted a bit of airflow.

Don't fly thru London Awful and huge U need 4 hrs to transfer cuz u have to tale buses to and fro from airplanes Bad business

Staff with low service level, forgetful. Temperature at 15 C and after asking twice to raise the temperature the crew did nothing.

I was disappointed with the quality of the food for an international flight also I wasn't given a toiletry bag which is customary in international flights.

They had about 20-25 people overbooked. Including me. Why is this?? I was put on a flight to NC an hour later with a 4 hour layover. I was supposed to be home at 1045am instead i was home at 7:30pm. An extra day to pay for dog care.

Boarding is not controlled as groups called was not enforced

Book Cheap Boulder Plane Tickets

Recent return flight deals

11/1Sat
2 stopsScandinavian Airlines
20h 11mDUB-DEN
24/1Fri
2 stopsScandinavian Airlines
43h 30mDEN-DUB
€526
11/1Sat
2 stopsScandinavian Airlines
20h 11mDUB-DEN
24/1Fri
2 stopsScandinavian Airlines
38h 00mDEN-DUB
€536
16/1Thu
1 stopIcelandair
13h 35mDUB-DEN
29/1Wed
1 stopIcelandair
11h 35mDEN-DUB
€669
4/12Wed
1 stopBritish Airways
13h 45mDUB-DEN
12/12Thu
1 stopBritish Airways
11h 50mDEN-DUB
€676
15/1Wed
1 stopUnited Airlines
16h 12mDUB-DEN
26/1Sun
1 stopUnited Airlines
12h 10mDEN-DUB
€691
14/1Tue
1 stopBritish Airways
13h 45mDUB-DEN
28/1Tue
2 stopsBritish Airways
14h 32mDEN-DUB
€692
15/1Wed
2 stopsUnited Airlines
17h 24mDUB-DEN
26/1Sun
1 stopUnited Airlines
14h 00mDEN-DUB
€697
21/4Mon
2 stopsAer Lingus
17h 50mORK-DEN
27/4Sun
2 stopsAer Lingus
20h 50mDEN-ORK
€732
3/3Mon
2 stopsIcelandair
18h 34mDUB-DEN
7/3Fri
1 stopIcelandair
11h 35mDEN-DUB
€735
11/4Fri
directAer Lingus
9h 45mDUB-DEN
18/4Fri
1 stopAer Lingus
23h 08mDEN-DUB
€757

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Recent one-way flight deals

19/1Sun
3 stops
51h 55mDUB-DEN
€312
15/1Wed
3 stops
41h 34mDUB-DEN
€317
2/2Sun
1 stopIcelandair
13h 35mDUB-DEN
€426
2/2Sun
1 stopIcelandair
13h 35mDUB-DEN
€523
30/1Thu
1 stopBritish Airways
13h 45mDUB-DEN
€583
30/1Thu
2 stopsBritish Airways
17h 36mDUB-DEN
€593
26/11Tue
1 stopAer Lingus
13h 45mDUB-DEN
€686
27/11Wed
1 stopAer Lingus
14h 45mDUB-DEN
€693
26/11Tue
3 stopsUnited Airlines
30h 24mDUB-DEN
€1,062
27/11Wed
3 stopsUnited Airlines
32h 44mDUB-DEN
€1,157

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