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$93+ Cheap flights from Philadelphia (PHL) 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 1/16. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — DEN
dic. 23 — dic. 301
lun. 12/23
lun. 12/30
1 adult, Economy
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The best prices from Philadelphia to Boulder are usually found in May or April, booked 79 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from Philadelphia to Boulder

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) 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 diciembre 18, 2024.

Round-trip from

$158
(Booking.com)

One-way from

$93
(Cheapflightsfares)

Popular in

December

Cheapest in

May

Average price

$378
From Philadelphia to Boulder
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One-way flight from Philadelphia to Boulder
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High demand for flights, 11% 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 Philadelphia to Boulder

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

This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/256:40 amPHL - DEN
Nonstop4h 35mFrontier
lun. 12/306:00 amDEN - PHL
1 stop15h 59mFrontier
Deal found 12/17$188
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/211:47 pmPHL - DEN
1 stop11h 47mMultiple Airlines
dom. 1/57:15 pmDEN - PHL
1 stop13h 31mMultiple Airlines
Deal found 12/17$312

Find flights from Philadelphia to Boulder within your budget

Customize your flight search to find flights from Philadelphia 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 diciembre 18, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

vie. 1/10

6:25 am-10:53 pm

1 stop18h 28m

Denver Intl

sáb. 1/11

12:50 am-8:01 am

1 stop29h 11m

$158

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mié. 1/29

8:10 am-10:32 am

Nonstop4h 22m

Denver Intl

mié. 1/29

5:50 pm-11:24 pm

Nonstop3h 34m

$201

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

jue. 1/23

9:45 am-12:10 pm

Nonstop4h 25m

Denver Intl

lun. 1/27

5:45 pm-11:15 pm

Nonstop3h 30m

$202

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

lun. 3/3

6:10 pm-11:04 pm

1 stop6h 54m

Denver Intl

lun. 3/10

11:59 pm-9:48 am

1 stop7h 49m

$208

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mié. 1/1

12:22 pm-9:24 pm

1 stop11h 02m

Denver Intl

mar. 1/7

6:45 am-11:48 am

1 stop27h 03m

$209

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mié. 1/15

9:00 am-11:16 am

Nonstop4h 16m

Denver Intl

mié. 1/29

7:00 am-12:44 pm

Nonstop3h 44m

$211

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mar. 1/7

2:55 pm-8:25 pm

1 stop7h 30m

Denver Intl

sáb. 2/8

4:54 pm-12:49 am

1 stop5h 55m

$256

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

jue. 1/16

9:53 pm-12:24 am

Nonstop4h 31m

$93

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mar. 1/28

3:40 pm-6:02 pm

Nonstop4h 22m

$101

PhiladelphiaDenver

PHL - DEN

PHLDEN

Philadelphia

mar. 3/18

6:00 am-12:09 pm

1 stop8h 09m

$104

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/17

Showing 1-10 of 16 results
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Best time to book a flight from Philadelphia to Boulder

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

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

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

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

Booking 79 days in advance of your planned departure date is, on average, the best time to get cheap flights from Philadelphia 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 Philadelphia to Boulder?

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

Find hourly flight availability from Philadelphia 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 diciembre 18, 2024.

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

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

Use this chart to determine the cheapest time to fly round-trip from Philadelphia to Boulder. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Philadelphia to Boulder flight should consider departing on Tuesday evenings when fares are most often at their lowest. Monday mornings 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 diciembre 18, 2024.
Read reviews from past customers who have flown Southwest, Delta and Frontier from Philadelphia to Boulder. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

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

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Alaska Airlines
8.0
Very good
9,554 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

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

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

JetBlue
7.4
Good
3,279 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

United Airlines
7.4
Good
9,055 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Comfort

8.1

Overall

8.1

Food

7.2

Boarding

8.2

Crew

8.7

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Related info for your journey

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

    If you book a flight to Boulder from Philadelphia, you will be flying from Philadelphia, which is the city’s only airport. Philadelphia (PHL) is located 7.0 mi from the center of Philadelphia. There are 3 flights from Philadelphia to Boulder per day from 7 different airlines.

  • How popular is this Philadelphia to Boulder flight route?

    This flight path from Philadelphia to Boulder was viewed by 171 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $93. Users have also found prices from $101 and $104 on United Airlines and JetBlue, respectively.

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

    The top 3 most reliable airlines when flying from Philadelphia to Boulder are United Airlines (93%), Air Canada (92%) and Frontier (89%).

  • What are the cheapest flights from Philadelphia to Boulder?

    On average you can expect to pay $772 for a flight from Philadelphia to Boulder. The cheapest flight overall is $90 while the most popular route, (Philadelphia - Denver Intl) is currently priced at $106.

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

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

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

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

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

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

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

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Alternative routes for Philadelphia to Boulder

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from Philadelphia to Boulder

Discover the top 7 airlines that operate flights from Philadelphia 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 diciembre 18, 2024.
AirlineCheapestAverageFlexibilityOn-time
Sun Country AirCheapest$82Average$275FlexibilityNo cancel feeOn-time83%
FrontierCheapest$88Average$206FlexibilityNo cancel feeOn-time62%
Allegiant AirCheapest$104Average$213FlexibilityNo cancel feeOn-time88%
SouthwestCheapest$179Average$406FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$189Average$470FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$191Average$420FlexibilityNo cancel feeOn-time71%
DeltaCheapest$221Average$384FlexibilityNo cancel feeOn-timeN/A
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