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$48+ Cheap flights from San Diego (SAN) 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 2/13. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — DEN
Dec 23 — Dec 301
Mon 12/23
Mon 12/30
1 adult, Economy
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The best prices from San Diego to Boulder are usually found in January or April, booked 53 days in advance, depart on a Tuesday or Wednesday and return on a Saturday

Cheap flight deals from San Diego to Boulder

Discover tips and strategies to find the most affordable flight options for your journey from San Diego (SAN) to Boulder (BD9). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 18, 2024.

Round-trip from

$76
(Cheapflightsfares)

One-way from

$48
(Cheapflightsfares)

Popular in

December

Cheapest in

January

Average price

$238
From San Diego to Boulder
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One-way flight from San Diego to Boulder
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High demand for flights, 9% potential price rise
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Best time to find cheap flights, 2% potential price drop
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Average for round-trip flights in December 2024
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Find flight deals from San Diego to Boulder

Cheapest flights from San Diego to Boulder
Explore the most affordable flight options available from San Diego to Boulder. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 18, 2024.

This eDestinos deal was found by Cheapflights users on 12/17. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/314:26 pmSAN - DEN
1 stop10h 28mFrontier
Mon 1/65:30 amDEN - SAN
1 stop10h 41mFrontier
Deal found 12/17$126
This eDestinos deal was found by Cheapflights users on 12/17. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/236:15 amSAN - DEN
1 stop25h 49mMultiple Airlines
Mon 1/61:25 pmDEN - SAN
2 stops26h 23mMultiple Airlines
Deal found 12/17$289
This United Airlines deal was found by Cheapflights users on 12/17. 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.
Tue 12/318:35 amSAN - DEN
Nonstop2h 28mUnited Airlines
Mon 1/64:07 pmDEN - SAN
Nonstop2h 30mUnited Airlines
Deal found 12/17$367
This Southwest deal was found by Cheapflights users on 12/16. 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 12/289:00 amSAN - DEN
1 stop4h 35mSouthwest
Thu 1/97:00 amDEN - SAN
2 stops7h 35mSouthwest
Deal found 12/16$447
This Alaska Airlines deal was found by Cheapflights users on 12/17. 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 12/242:53 pmSAN - DEN
1 stop19h 04mAlaska Airlines
Thu 1/912:04 pmDEN - SAN
2 stops9h 46mAlaska Airlines
Deal found 12/17$464

Find flights from San Diego to Boulder within your budget

Customize your flight search to find flights from San Diego 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 December 18, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Fri 1/24

12:31 pm-3:59 pm

Nonstop2h 28m

Denver Intl

Mon 1/27

10:52 pm-12:29 am

Nonstop2h 37m

$76

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 1/18

6:15 am-6:37 pm

2 stops11h 22m

Denver Intl

Sun 1/19

4:20 pm-5:59 pm

Nonstop2h 39m

$119

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 1/18

5:50 pm-9:10 pm

Nonstop2h 20m

Denver Intl

Sun 1/19

9:40 am-11:15 am

Nonstop2h 35m

$178

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Tue 1/21

10:15 am-3:20 pm

1 stop4h 05m

Denver Intl

Fri 1/24

5:40 am-9:10 am

1 stop4h 30m

$216

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 1/18

4:11 pm-7:39 pm

Nonstop2h 28m

Denver Intl

Wed 1/22

10:15 am-2:49 pm

1 stop5h 34m

$222

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Fri 2/21

6:15 am-6:59 pm

2 stops11h 44m

Denver Intl

Tue 2/25

7:00 am-12:46 pm

1 stop6h 46m

$234

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Thu 2/13

6:25 am-9:56 am

Nonstop2h 31m

$48

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Wed 1/22

1:34 pm-11:29 pm

2 stops8h 55m

$106

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Wed 2/19

10:59 am-4:08 pm

1 stop4h 09m

$108

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Tue 1/14

5:45 pm-11:00 pm

1 stop4h 15m

$118

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/18

Showing 1-10 of 12 results
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Best time to book a flight from San Diego to Boulder

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

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

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

Use this chart to determine the optimal time to book a round-trip flight from San Diego to Boulder. Price data was last updated on December 13, 2024.

Booking 53 days in advance of your planned departure date is, on average, the best time to get cheap flights from San Diego to Boulder. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from San Diego to Boulder?

Currently, October is the cheapest month in which you can book a flight from San Diego to Boulder (average of $197). Flying from San Diego to Boulder in March is currently the most expensive (average of $271). 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 SAN to BD9?

Find hourly flight availability from San Diego 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 December 18, 2024.

When flying from San Diego to Boulder, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

What is the cheapest day to fly from San Diego to Boulder?

Use this chart to determine the cheapest time to fly round-trip from San Diego to Boulder. Price data was last updated on March 31, 2024.

Travelers seeking maximum savings on their San Diego to Boulder flight should consider departing on Saturday evenings when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

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 December 18, 2024.
Read reviews from past customers who have flown Southwest, Frontier and Alaska Airlines from San Diego to Boulder. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Southwest
8.1
Very good
4,848 reviews
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Alaska Airlines
8.0
Very good
9,552 reviews
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Delta
8.0
Very good
8,604 reviews
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

United Airlines
7.4
Good
9,059 reviews
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Frontier
6.1
Okay
3,479 reviews
Southwest
8.1
Very good
4,848 reviews

Crew

8.7

Food

7.2

Comfort

8.1

Entertainment

7.7

Boarding

8.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Related info for your journey

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

    San Diego (SAN), located 2.6 mi from the city center, is the airport you fly out of when you book flights from San Diego to Boulder. 5 airlines have flights from San Diego to Boulder on a regular basis. Booking flights from San Diego to Boulder should not be difficult; the airport handles an average of 11 outbound flights to Boulder per day.

  • How popular is this San Diego to Boulder flight route?

    Flights from San Diego to Boulder have been viewed 239 times in the past calendar month.

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

    One-way options have recently been found by users for as low as $48 on Frontier. Other airlines that offer cheap prices include Alaska Airlines from $106 and Delta from $108 one-way.

  • What are the most reliable airlines from San Diego to Boulder?

    No one likes to see their flight delayed. When booking a flight from San Diego to Boulder consider choosing Copa Airlines (92%), United Airlines (89%) or Air Canada (87%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from San Diego to Boulder?

    On average you can expect to pay $1,031 for a flight from San Diego to Boulder. The cheapest flight overall is $49 while the most popular route, (San Diego - Denver Intl) is currently priced at $68.

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

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

  • How can I find direct flights from San Diego to Boulder?

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

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

    Yes. Cheapflights offers flight deals from San Diego 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 San Diego to Boulder?

    Currently, October is the cheapest month in which you can book a flight from San Diego to Boulder (average of $197). Flying from San Diego to Boulder in March is currently the most expensive (average of $271). 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 5 airlines flying from San Diego to Boulder

Discover the top 5 airlines that operate flights from San Diego 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 December 18, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$57Average$149FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$158Average$341FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$161Average$355FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$174Average$350FlexibilityNo cancel feeOn-time71%
DeltaCheapest$195Average$265FlexibilityNo cancel feeOn-timeN/A
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