€437 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 21/5. 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

€437
Best time to beat the crowds (9% less expensive on average)
Most popular time to fly (20% more expensive on average)
Flight from Dublin to Denver

FAQs - booking Boulder flights

  • How long is the flight to Boulder?

    Flights from Dublin9h 10m
  • 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 €1,478
  • 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 9035 reviews
7.3Comfort
8.1Crew
7.1Entertainment
6.7Food
7.7Boarding
Airline reviews

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

4.0 OkayChris, Dec 2024FLL - DEN
Read more United Airlines reviews

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 4 hours late. Almost missed my connecting flight no food or drinks on connecting flight. Overall terrible experience

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!

Again, lines for boarding are a problem in iceland. The flight itself was fine and very smooth. No complaints. We would definitely fly icelandair again.

take snacks and food. purchase options in flight are not great

Had a screaming child next to us. Not the airline’s fault but still annoying.

Icelandair flight was excellent. The checkin and security arrangements for Saga Premium passengers at Newark was very poor - our checkin opened much later than the normal and our security queue simply led us to the back of the normal queue. Someone was having a laugh surely!

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.

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

There was a very drunk and disruptive passenger who was on the plane, right behind me. He was already drunk before boarding but was still let on the plane. He kept kicking and hitting the back of my chair the entire flight. It was an early morning flight and had zero rest on that leg

Really lovely trip and flight. The flight staff were so accommodating and warm throughout!

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.

No land services during boarding, specially while moving from terminal to another

Even the carry-ons were not allowed and upon getting down, we had the wait for the longest time for the baggage to put on the jet aisle. We had a short connection which British Airways kept changing and made out entire experience poor. I would never fly BA again.

The seat was very uncomfortable. It helped to use the foot rest. Could not sleep because of the seat.

The seats are incredibly uncomfortable. My luggage didn't make it on the flight from London to Nashville.

The plane itself is old and way overcrowded. The crew do a great job of trying to mitigate. It is just uncomfortable for over 8 hours, bearable, but barely. Boarding, and the baggage game, is ludicrous. Why charge extra to check bags when there is not enough room for everyone to "carry-on" and checking is needed? I do not think these issues would be different with other airlines, I believe it is the attitude that squeezes every penny out of each traveler.

Expected a lot better service paying for a business class seat. Seemed to be short on staff and did not get the service I expected.

I flew Club World and was SHOCKED at how totally absent the crew were for the duration of the flight. So much so that we received no drink service other than the post-departure cocktail and that was it. Wasn't even offered tea/coffee and the in-flight attention was so bad that literally minutes before landing the one crew member for our row was scrambling to pick up left-behind water bottles, glassware, trash. And the rest of the crew had already stowed all carts, he was cramming the trash into the lavatory trash can and was stashing the glassware frantically in the galley as we were on final approach. He was so scrambled he left two overhead lockers wide open (that he'd opened) for landing. Unbelievable!

The flight was several times changed. That was inconvenient, to sah the least.

They lost my special meal request and tried to tell me I didn't request it. I had the proof. Then they tried to get me to eat food I can't eat. No apologies

British airways keeps canceling our flights. I won’t be booking any future flights with them

Book Cheap Boulder Plane Tickets

Recent return flight deals

3/2Mon
2 stops
45h 53mDUB-DEN
10/2Mon
1 stop
11h 35mDEN-DUB
€538
3/2Mon
2 stops
45h 53mDUB-DEN
10/2Mon
1 stop
11h 35mDEN-DUB
€545
16/1Thu
1 stopIcelandair
13h 35mDUB-DEN
29/1Wed
1 stopIcelandair
11h 35mDEN-DUB
€604
13/1Mon
1 stopBritish Airways
25h 55mDUB-DEN
26/1Sun
1 stopBritish Airways
19h 05mDEN-DUB
€608
12/1Sun
1 stopBritish Airways
27h 00mDUB-DEN
22/1Wed
2 stopsBritish Airways
16h 16mDEN-DUB
€621
9/4Wed
1 stopIcelandair
13h 45mDUB-DEN
15/4Tue
1 stopIcelandair
11h 25mDEN-DUB
€634
12/1Sun
1 stopUnited Airlines
15h 53mDUB-DEN
25/1Sat
1 stopUnited Airlines
14h 00mDEN-DUB
€738
12/1Sun
2 stopsUnited Airlines
17h 40mDUB-DEN
25/1Sat
1 stopUnited Airlines
16h 15mDEN-DUB
€739
13/4Sun
directAer Lingus
9h 45mDUB-DEN
24/4Thu
1 stopAer Lingus
13h 02mDEN-DUB
€764
13/4Sun
directAer Lingus
9h 45mDUB-DEN
23/4Wed
directAer Lingus
8h 35mDEN-DUB
€884

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Recent one-way flight deals

21/5Wed
1 stopIcelandair
13h 45mDUB-DEN
€437
21/5Wed
1 stopIcelandair
13h 45mDUB-DEN
€444
21/3Fri
2 stops
33h 51mDUB-DEN
€499
21/3Fri
3 stops
32h 01mDUB-DEN
€541
21/5Wed
directAer Lingus
9h 45mDUB-DEN
€593
30/1Thu
2 stopsBritish Airways
17h 36mDUB-DEN
€597
21/5Wed
directAer Lingus
9h 45mDUB-DEN
€606
29/4Tue
1 stopBritish Airways
14h 50mDUB-DEN
€615
29/4Tue
3 stopsUnited Airlines
19h 55mDUB-DEN
€1,152
2/6Mon
3 stopsUnited Airlines
19h 05mDUB-DEN
€1,153

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Last minute flights to Boulder

Last minute flight, train and bus deals

24/12Tue
multi-stopBritish Airways
13h 45mDUB-DEN
31/12Tue
multi-stopBritish Airways
19h 05mDEN-DUB
€743
24/12Tue
multi-stopBritish Airways
13h 45mDUB-DEN
31/12Tue
multi-stopBritish Airways
13h 07mDEN-DUB
€808
24/12Tue
multi-stopUnited Airlines
17h 23mDUB-DEN
31/12Tue
multi-stopUnited Airlines
16h 10mDEN-DUB
€821
22/12Sun
multi-stopUnited Airlines
14h 38mDUB-DEN
2/1Thu
multi-stopUnited Airlines
21h 05mDEN-DUB
€888
22/12Sun
multi-stopUnited Airlines
20h 13mDUB-DEN
2/1Thu
multi-stopUnited Airlines
21h 05mDEN-DUB
€893
22/12Sun
multi-stop
42h 18mDUB-DEN
1/1Wed
multi-stop
26h 11mDEN-DUB
€2,361
24/12Tue
multi-stop
35h 50mDUB-DEN
30/12Mon
multi-stop
39h 36mDEN-DUB
€2,501
26/12Thu
multi-stopTAP AIR PORTUGAL
36h 10mDUB-DEN
3/1Fri
multi-stopTAP AIR PORTUGAL
22h 40mDEN-DUB
€3,027
22/12Sun
multi-stop
31h 50mDUB-DEN
1/1Wed
multi-stop
26h 11mDEN-DUB
€3,066

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