Boulder

$46+ 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 12/18. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — DEN
Nov 26 — Dec 31
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The best prices from San Diego to Boulder are usually found in April or January, booked 53 days in advance, depart on a Saturday or Tuesday 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 November 21, 2024.

Popular in

March

Cheapest in

April

Round-trip from

$78
(Frontier)

One-way from

$46
(Kiwi.com)
High demand for flights, 19% potential price rise
Best time to find cheap flights, 21% potential price drop
From San Diego to Boulder
One-way flight from San Diego to Boulder

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 November 21, 2024.

This Frontier deal was found by Cheapflights users on 11/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/101:48 pmSAN - DEN
Nonstop2h 30mFrontier
Mon 12/169:22 amDEN - SAN
Nonstop2h 36mFrontier
Deal found 11/20$78
This eDestinos deal was found by Cheapflights users on 11/20. 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.
Sat 12/286:06 pmSAN - DEN
2 stops18h 19mMultiple Airlines
Thu 1/910:15 pmDEN - SAN
Nonstop2h 34mMultiple Airlines
Deal found 11/20$181
This Delta deal was found by Cheapflights users on 11/20. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/116:30 amSAN - DEN
1 stop15h 44mDelta
Mon 12/165:25 amDEN - SAN
1 stop13h 47mDelta
Deal found 11/20$183
This Alaska Airlines deal was found by Cheapflights users on 11/20. 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.
Sun 12/157:00 amSAN - DEN
1 stop15h 59mAlaska Airlines
Tue 12/1712:45 pmDEN - SAN
1 stop7h 30mAlaska Airlines
Deal found 11/20$269
This American Airlines deal was found by Cheapflights users on 11/20. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/249:58 amSAN - DEN
1 stop7h 16mAmerican Airlines
Sat 12/2812:24 pmDEN - SAN
1 stop6h 59mAmerican Airlines
Deal found 11/20$272
This United Airlines deal was found by Cheapflights users on 11/20. 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.
Fri 12/137:00 amSAN - DEN
Nonstop2h 28mUnited Airlines
Sat 12/148:00 amDEN - SAN
Nonstop2h 28mUnited Airlines
Deal found 11/20$277

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 2,629,791 searches. Data last updated November 21, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Tue 12/10

1:48 pm-5:18 pm

Nonstop2h 30m

Denver Intl

Mon 12/16

9:22 am-10:58 am

Nonstop2h 36m

$78

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 12/28

6:06 pm-1:25 pm

2 stops18h 19m

Denver Intl

Thu 1/9

10:15 pm-11:49 pm

Nonstop2h 34m

$181

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Wed 12/11

6:30 am-11:14 pm

1 stop15h 44m

Denver Intl

Mon 12/16

5:25 am-6:12 pm

1 stop13h 47m

$183

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Thu 2/20

4:30 pm-10:35 pm

1 stop5h 05m

Denver Intl

Tue 2/25

7:46 am-12:03 pm

1 stop5h 17m

$207

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Tue 2/4

8:20 am-10:36 pm

2 stops13h 16m

Denver Intl

Fri 2/7

2:07 pm-7:25 pm

1 stop6h 18m

$234

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 1/11

7:00 am-10:28 am

Nonstop2h 28m

Denver Intl

Sun 1/12

7:40 pm-9:10 pm

Nonstop2h 30m

$237

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Wed 12/18

11:15 am-2:41 pm

Nonstop2h 26m

$46

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Wed 3/5

6:15 am-2:41 pm

1 stop7h 26m

$88

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Thu 11/28

6:57 pm-1:01 pm

1 stop17h 04m

$92

San DiegoDenver

SAN - DEN

SANDEN

San Diego

Sat 3/1

10:20 am-3:27 pm

1 stop4h 07m

$99

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/21

Showing 1-10 of 14 results
1
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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 November 15, 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 $270). 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 November 21, 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.

Weekly flight availability from San Diego to Boulder

Explore weekly flight availability from San Diego 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 November 21, 2024.

The most flights from SAN to BD9 are scheduled on a Wednesday (28 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (12 on average).

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 November 21, 2024.
Read reviews from past customers who have flown Frontier, Delta and American 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.
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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

8.1
Very good
5,015 reviews
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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

8.0
Very good
9,458 reviews
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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

8.0
Very good
8,758 reviews
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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

7.4
Good
9,172 reviews
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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

7.2
Good
10,000 reviews
8.1
Very good
5,015 reviews

Food

7.2

Comfort

8.1

Boarding

8.2

Entertainment

7.7

Crew

8.7

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 21 outbound flights to Boulder per day.

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

  • 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 $46 on Frontier. Other airlines that offer cheap prices include United Airlines from $88 and American Airlines from $99 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 SWISS (100%), Copa Airlines (94%) or United Airlines (85%) 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 $892 for a flight from San Diego to Boulder. The cheapest flight overall is $50 while the most popular route, (San Diego - Denver Intl) is currently priced at $122.

  • 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 $270). 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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Alternative routes for San Diego to Boulder

See prices for flight routes from nearby airports that may be better suited for you.

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 2,629,791 searches. Data last updated November 21, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$57Average$148FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$158Average$331FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$160Average$354FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$177Average$348FlexibilityNo cancel feeOn-time71%
DeltaCheapest$195Average$256FlexibilityNo cancel feeOn-timeN/A
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