Boulder

$53+ Cheap flights from San Francisco (SFO) 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 1/6. Fares are subject to change and may not be available on all flights or dates of travel.
SFO — DEN
Nov 26 — Dec 31
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The best prices from San Francisco to Boulder are usually found in April or January, booked 40 days in advance, depart on a Saturday or Tuesday and return on a Saturday

Cheap flight deals from San Francisco to Boulder

Discover tips and strategies to find the most affordable flight options for your journey from San Francisco (SFO) 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

June

Cheapest in

April

Round-trip from

$93
(Frontier)

One-way from

$53
(Cheapflightsfares)
High demand for flights, 19% potential price rise
Best time to find cheap flights, 13% potential price drop
From San Francisco to Boulder
One-way flight from San Francisco to Boulder

Find flight deals from San Francisco to Boulder

Cheapest flights from San Francisco to Boulder
Explore the most affordable flight options available from San Francisco 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.
Sat 12/146:55 amSFO - DEN
Nonstop2h 35mFrontier
Sun 12/1510:51 amDEN - SFO
Nonstop2h 59mFrontier
Deal found 11/20$93
This Booking.com 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/211:59 pmSFO - DEN
1 stop11h 32mMultiple Airlines
Thu 12/510:18 pmDEN - SFO
1 stop11h 30mMultiple Airlines
Deal found 11/20$184
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 12/111:39 pmSFO - DEN
1 stop4h 11mDelta
Tue 12/177:45 pmDEN - SFO
1 stop5h 04mDelta
Deal found 11/20$216
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.
Wed 12/184:17 pmSFO - DEN
2 stops16h 24mAlaska Airlines
Thu 12/198:22 pmDEN - SFO
1 stop12h 35mAlaska Airlines
Deal found 11/20$264
This United Airlines deal was found by Cheapflights users on 11/21. 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.
Sat 12/147:10 pmSFO - DEN
Nonstop2h 37mUnited Airlines
Mon 12/167:45 pmDEN - SFO
1 stop5h 19mUnited Airlines
Deal found 11/21$267

Find flights from San Francisco to Boulder within your budget

Customize your flight search to find flights from San Francisco 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 FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Sat 12/14

6:55 am-10:30 am

Nonstop2h 35m

Denver Intl

Sun 12/15

10:51 am-12:50 pm

Nonstop2h 59m

$93

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Mon 2/17

8:10 pm-11:51 pm

Nonstop2h 41m

Denver Intl

Tue 3/4

12:38 pm-8:09 pm

1 stop8h 31m

$182

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Sat 2/22

4:09 pm-10:35 pm

1 stop5h 26m

Denver Intl

Thu 2/27

7:42 pm-11:59 pm

1 stop5h 17m

$207

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Wed 12/11

1:39 pm-6:50 pm

1 stop4h 11m

Denver Intl

Tue 12/17

7:45 pm-11:49 pm

1 stop5h 04m

$216

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Mon 1/6

7:55 am-11:20 am

Nonstop2h 25m

Denver Intl

Fri 1/10

3:50 pm-8:35 pm

1 stop5h 45m

$235

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Wed 2/5

8:00 am-10:36 pm

2 stops13h 36m

Denver Intl

Sun 2/9

7:00 am-1:47 pm

1 stop7h 47m

$237

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Mon 1/6

2:29 pm-8:09 pm

1 stop4h 40m

$53

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Tue 2/18

2:43 pm-11:29 pm

1 stop7h 46m

$88

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Tue 3/4

4:27 pm-10:28 pm

1 stop5h 01m

$93

San FranciscoDenver

SFO - DEN

SFODEN

San Francisco

Tue 2/18

4:09 pm-10:35 pm

1 stop5h 26m

$98

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/20

Showing 1-10 of 14 results
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Best time to book a flight from San Francisco to Boulder

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

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

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

Use this chart to determine the optimal time to book a round-trip flight from San Francisco to Boulder. Price data was last updated on November 15, 2024.

Booking 40 days in advance of your planned departure date is, on average, the best time to get cheap flights from San Francisco 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 Francisco to Boulder?

Currently, October is the cheapest month in which you can book a flight from San Francisco to Boulder (average of $197). Flying from San Francisco 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 SFO to BD9?

Find hourly flight availability from San Francisco 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.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from San Francisco to Boulder as you normally would.

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

Use this chart to determine the cheapest time to fly round-trip from San Francisco to Boulder. Price data was last updated on October 6, 2024.

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

Weekly flight availability from San Francisco to Boulder

Explore weekly flight availability from San Francisco 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 SFO to BD9 are scheduled on a Wednesday (57 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (39 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.
To help decide which airline to fly from San Francisco to Boulder, see what other customers have to say about Frontier, American Airlines and Delta. 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

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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

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

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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

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

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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

8.0
Very good
8,759 reviews
8.1
Very good
5,015 reviews

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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

7.4
Good
9,173 reviews
8.1
Very good
5,015 reviews

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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

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

Entertainment

7.7

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.2

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 Francisco 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 Francisco to Boulder?

    Located just 11.8 mi from the city center, San Francisco is the airport most travelers will use when flying to Boulder from San Francisco. Booking flights from San Francisco (SFO) to Boulder should be relatively easy as there are 47 daily outbound flights to Boulder from 6 different airlines.

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

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $53. Users have also found prices from $88 and $93 on Alaska Airlines and United Airlines, respectively.

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

    Consider SWISS (100%), United Airlines (89%) or Air Canada (88%) when booking your flight. These represent the most reliable airlines when flying from San Francisco to Boulder.

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

    The cheapest flight price from San Francisco to Boulder is $59. On average you can expect to pay $821. The most popular route, (San Francisco - Denver Intl), can usually be booked for $57.

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

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

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

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

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

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

    Currently, October is the cheapest month in which you can book a flight from San Francisco to Boulder (average of $197). Flying from San Francisco 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 Francisco to Boulder

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

Top 6 airlines flying from San Francisco to Boulder

Discover the top 6 airlines that operate flights from San Francisco 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$59Average$154FlexibilityNo cancel feeOn-time62%
Alaska AirlinesCheapest$116Average$320FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$151Average$309FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$153Average$374FlexibilityNo cancel feeOn-time69%
DeltaCheapest$195Average$299FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$198Average$478FlexibilityNo cancel feeOn-time71%
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