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$104+ Cheap flights from Boston (BOS) 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 5/11. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — DEN
Apr 26 — May 31
Sun 4/26
Sun 5/3
1 adult, Economy
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Cheapflights Tip: The best prices from Boston Logan Intl to Boulder are usually found in November or May, booked 64 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from Boston to Boulder

Cheapest flights from Boston to Boulder
Explore the most affordable flight options available from Boston to Boulder. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 27, 2026.

This Cheapflightsfares deal was found by Cheapflights users on 3/25. 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 5/1310:07 am
BOS
-
DEN
1 stop24h 17m
Frontier
Sun 5/176:03 am
DEN
-
BOS
1 stop27h 03m
Frontier
Deal found 3/25$209
This Southwest deal was found by Cheapflights users on 3/26. 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.
Sat 4/259:25 am
BOS
-
DEN
1 stop8h 10m
Southwest
Sat 5/25:35 pm
DEN
-
BOS
1 stop12h 55m
Southwest
Deal found 3/26$210
This Southwest deal was found by Cheapflights users on 3/26. 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.
Tue 4/149:15 am
BOS
-
DEN
1 stop8h 45m
Southwest
Thu 4/167:35 am
DEN
-
BOS
1 stop8h 30m
Southwest
Deal found 3/26$211
This CheapOair deal was found by Cheapflights users on 3/25. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/137:31 pm
BOS
-
DEN
Nonstop4h 42m
Multiple Airlines
Fri 5/156:03 am
DEN
-
BOS
1 stop27h 03m
Multiple Airlines
Deal found 3/25$212
This Kiwi.com deal was found by Cheapflights users on 3/25. 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.
Thu 4/2312:31 pm
BOS
-
DEN
2 stops11h 58m
Frontier
Wed 4/2912:00 pm
DEN
-
BOS
1 stop21h 33m
Frontier
Deal found 3/25$213
This Expedia deal was found by Cheapflights users on 3/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/95:30 am
BOS
-
DEN
1 stop8h 39m
Multiple Airlines
Sat 4/1111:31 pm
DEN
-
BOS
Nonstop3h 48m
Multiple Airlines
Deal found 3/26$214
This Southwest deal was found by Cheapflights users on 3/23. 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.
Mon 4/136:45 pm
BOS
-
DEN
1 stop6h 15m
Southwest
Tue 4/1411:45 am
DEN
-
BOS
2 stops7h 35m
Southwest
Deal found 3/23$215
This CheapOair deal was found by Cheapflights users on 3/25. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/158:44 am
BOS
-
DEN
1 stop7h 48m
Multiple Airlines
Tue 5/1911:28 pm
DEN
-
BOS
Nonstop3h 54m
Multiple Airlines
Deal found 3/25$216
This Southwest deal was found by Cheapflights users on 3/26. 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.
Tue 4/147:20 am
BOS
-
DEN
1 stop6h 30m
Southwest
Sat 4/1811:40 am
DEN
-
BOS
2 stops7h 45m
Southwest
Deal found 3/26$217
This Kiwi.com deal was found by Cheapflights users on 3/25. 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.
Tue 4/1412:40 pm
BOS
-
DEN
1 stop25h 29m
Multiple Airlines
Sat 4/187:35 am
DEN
-
BOS
1 stop13h 50m
Multiple Airlines
Deal found 3/25$218
This Expedia deal was found by Cheapflights users on 3/25. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/812:42 pm
BOS
-
DEN
1 stop12h 22m
Multiple Airlines
Sat 4/1111:31 pm
DEN
-
BOS
Nonstop3h 48m
Multiple Airlines
Deal found 3/25$219
This Southwest deal was found by Cheapflights users on 3/22. 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.
Thu 4/235:15 am
BOS
-
DEN
Nonstop4h 30m
Southwest
Tue 5/56:00 pm
DEN
-
BOS
Nonstop4h 05m
Southwest
Deal found 3/22$220

Find flight deals from Boston to Boulder

Keep the following information in mind while searching for Boston to Boulder flight deals. Data was last updated March 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$209
(Orbitz)

One-way from

$104
(Cheapflightsfares)

Popular in

February

Cheapest in

November

Average price

$329
Provider with most accurate pricing for Boston Logan Intl-Denver Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Boston Logan Intl-Denver Intl flights.
Search Deals
From Boston Logan Intl to Boulder
Search Deals
One-way flight from Boston Logan Intl to Boulder
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($13 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 0% potential price decrease ($4 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Boston 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 March 27, 2026.
Use the filters below to find and compare flights from Boston to Boulder that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Thu 4/23

7:09 am-10:00 am

Nonstop4h 51m

Denver Intl

Thu 4/30

6:00 am-1:51 pm

1 stop5h 51m

$217

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Mon 5/4

6:45 pm-11:00 pm

1 stop6h 15m

Denver Intl

Thu 5/7

11:55 pm-8:05 am

1 stop6h 10m

$228

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Tue 5/5

4:52 pm-7:40 pm

Nonstop4h 48m

Denver Intl

Fri 5/8

4:45 pm-12:59 am

1 stop6h 14m

$235

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Thu 4/9

5:15 am-7:45 am

Nonstop4h 30m

Denver Intl

Sat 4/11

5:45 pm-11:50 pm

Nonstop4h 05m

$252

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Fri 6/5

5:50 pm-10:55 pm

1 stop7h 05m

Denver Intl

Mon 6/8

8:40 am-6:10 pm

1 stop7h 30m

$263

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Tue 9/15

10:51 am-3:17 pm

1 stop6h 26m

Denver Intl

Tue 9/22

3:56 pm-9:58 pm

Nonstop4h 02m

$277

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Wed 6/10

6:25 pm-10:35 pm

1 stop6h 10m

Denver Intl

Sun 6/14

7:50 pm-1:45 am

Nonstop3h 55m

$292

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Tue 5/19

8:10 am-2:05 pm

2 stops7h 55m

Denver Intl

Sun 5/24

7:15 am-4:05 pm

1 stop6h 50m

$300

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Sat 8/22

9:34 am-2:16 pm

1 stop6h 42m

Denver Intl

Sat 8/29

11:59 pm-5:59 am

Nonstop4h 00m

$304

BostonDenver

BOS - DEN

BOSDEN

Boston Logan Intl

Tue 6/9

8:05 am-2:04 pm

1 stop7h 59m

Denver Intl

Mon 6/15

7:00 pm-6:05 am

1 stop9h 05m

$312

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/25

Showing 1-10 of 24 resultsSorted by cheapest first
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2
3

Best time to book a flight from Boston to Boulder

Have a flexible travel schedule? Discover the best time to fly to Boulder from Boston 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 Boston to Boulder

How far ahead should I book a flight from Boston to Boulder?

Use this chart to determine the optimal time to book a round-trip flight from Boston to Boulder. Price data was last updated on March 13, 2026.

To ensure you get the cheapest price possible for a flight from Boston to Boulder, you should look to book at least 64 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 Boston to Boulder?

Currently, November is the cheapest month in which you can book a flight from Boston to Boulder (average of $87). Flying from Boston to Boulder in January is currently the most expensive (average of $158). 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 BOS to BD9?

Find hourly flight availability from Boston 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 March 27, 2026.

When flying from Boston to Boulder, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 23% versus a flight at noon.

What is the cheapest day to fly from Boston to Boulder?

Use this chart to determine the cheapest time to fly round-trip from Boston to Boulder. Price data was last updated on March 23, 2026.

Travelers seeking maximum savings on their Boston to Boulder flight should consider departing on Thursday 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 Boston to Boulder

Explore weekly flight availability from Boston 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 March 27, 2026.

The most flights from BOS to BD9 are scheduled on a Thursday (14 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (2 on average).

How much does it cost to fly round-trip from Boston to Boulder?

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 March 27, 2026.
Get a feel of what it's like to fly with Southwest,Delta, andUnited Airlines from Boston to Boulder by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,331 reviews
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Delta
7.9
Good
8,339 reviews
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
United Airlines
7.4
Good
9,494 reviews
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
JetBlue
7.2
Good
2,908 reviews
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.7
Fair
3,014 reviews
Southwest
8.0
Very good
4,331 reviews

Boarding

8.1

Overall

8.0

Food

7.0

Comfort

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Boston 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 Boston to Boulder?

    For a flight from Boston to Boulder, you will be flying from Logan Intl. Boston Logan Intl (BOS) is just 2.6 mi from the center of the city. Logan Intl is the only Boston airport and it handles 6 outbound flights to Boulder per day. 7 airlines have flights to Boulder from Boston Logan Intl on a regular basis.

  • How popular is this Boston to Boulder flight route?

    Flights from Boston Logan Intl to Boulder have been viewed 94 times in the past calendar month.

  • How long is the flight from Boston to Boulder?

    United Airlines and Southwest can get you from Boston to Boulder in just under 4h 51m. Your travel time can differ by up to 1h 24m. Boston and Boulder are separated by a distance of 1748 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Boston to Boulder one-way?

    One-way options have recently been found by users for as low as $73 on Frontier. Other airlines that offer cheap prices include JetBlue from $90 and American Airlines from $93 one-way.

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

    Consider United Airlines (86%), ITA Airways (83%) or EL AL (82%) when booking your flight. These represent the most reliable airlines when flying from Boston to Boulder.

  • What are the cheapest flights from Boston to Boulder?

    Looking for the cheapest flight from Boston to Boulder? While on average our users pay $742, our data indicates the cheapest price to be $116. The most popular route (Boston Logan Intl - Denver Intl), is priced around $115.

  • Can I find deals for flights from Boston to Boulder that include hotel bookings?

    Yes. In addition to deals on Boston to Boulder flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Boston to Boulder?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Boston to Boulder.

  • Can I find deals for business class flights from Boston to Boulder?

    Yes. Cheapflights offers flight deals from Boston 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 Boston to Boulder?

    Currently, November is the cheapest month in which you can book a flight from Boston to Boulder (average of $87). Flying from Boston to Boulder in January is currently the most expensive (average of $158). 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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Top 7 airlines flying from Boston to Boulder

Discover the top 7 airlines that operate flights from Boston 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 March 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$95Average$257FlexibilityNo cancel feeOn-time62%
DeltaCheapest$108Average$337FlexibilityNo cancel feeOn-timeN/A
JetBlueCheapest$128Average$292FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$374FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$186Average$377FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$196Average$374FlexibilityNo cancel feeOn-time71%
Alaska AirlinesCheapest$255Average$331FlexibilityNo cancel feeOn-time75%

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