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Sofia

$515+ Cheap flights from Denver (DEN) to Sofia (SOF)

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 9/10. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SOF
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheapflights Tip: The best prices from Denver Intl to Sofia are usually found in April or February, booked 48 days in advance, depart on a Thursday or Sunday and return on a Friday

Cheap flight deals from Denver to Sofia

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) to Sofia (SOF). 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 June 12, 2025.

Round-trip from

$599
(United Airlines)

One-way from

$515
(United Airlines)

Popular in

May

Cheapest in

April

Average price

$1,215
From Denver Intl to Sofia
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One-way flight from Denver Intl to Sofia
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Highest demand for flights based on searches. 9% potential increase in price ($92 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($34 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from Denver to Sofia

Cheapest flights from Denver to Sofia
Explore the most affordable flight options available from Denver to Sofia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This United Airlines deal was found by Cheapflights users on 6/12. 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 10/285:20 pmDEN - SOF
1 stop21h 25mUnited Airlines
Fri 12/56:15 amSOF - DEN
2 stops22h 50mUnited Airlines
Deal found 6/12$599
This Air Canada deal was found by Cheapflights users on 6/12. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2811:15 amDEN - SOF
2 stops18h 35mAir Canada
Fri 12/56:15 amSOF - DEN
2 stops22h 50mAir Canada
Deal found 6/12$603
This FlightHub deal was found by Cheapflights users on 6/12. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/285:20 pmDEN - SOF
1 stop17h 00mLufthansa
Fri 12/56:05 amSOF - DEN
1 stop17h 30mLufthansa
Deal found 6/12$609
This FlightHub deal was found by Cheapflights users on 6/12. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/237:50 pmDEN - SOF
1 stop27h 45mTurkish Airlines
Sat 9/69:25 amSOF - DEN
1 stop17h 30mTurkish Airlines
Deal found 6/12$634
This Gotogate deal was found by Cheapflights users on 6/10. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/89:40 amDEN - SOF
2 stops23h 10mMultiple Airlines
Wed 10/226:15 amSOF - DEN
1 stop18h 20mMultiple Airlines
Deal found 6/10$650
This Austrian Airlines deal was found by Cheapflights users on 6/11. 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 Austrian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/309:36 amDEN - SOF
2 stops20h 44mAustrian Airlines
Tue 10/78:00 amSOF - DEN
2 stops17h 35mAustrian Airlines
Deal found 6/11$890
This SWISS deal was found by Cheapflights users on 6/12. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/145:50 pmDEN - SOF
1 stop31h 15mSWISS
Tue 7/291:15 pmSOF - DEN
1 stop36h 05mSWISS
Deal found 6/12$929
This American Airlines deal was found by Cheapflights users on 6/12. 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 9/26:35 pmDEN - SOF
1 stop17h 05mAmerican Airlines
Wed 9/109:30 pmSOF - DEN
1 stop27h 55mAmerican Airlines
Deal found 6/12$3,845
This British Airways deal was found by Cheapflights users on 6/12. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/25:06 pmDEN - SOF
2 stops59h 24mBritish Airways
Mon 9/88:00 pmSOF - DEN
2 stops33h 00mBritish Airways
Deal found 6/12$3,906

Cheapflights Fare Finder

Customize your flight search to find flights from Denver to Sofia 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 June 12, 2025.
Use the filters below to find and compare flights from Denver to Sofia that are best for you.

Fly from

Denver

Fly to

Sofia

Route

Depart

Return

Price

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 10/28

5:20 pm-10:45 pm

1 stop21h 25m

Sofia

Fri 12/5

6:15 am-8:05 pm

2 stops22h 50m

$599

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 10/28

11:15 am-1:50 pm

2 stops18h 35m

Sofia

Fri 12/5

6:15 am-8:05 pm

2 stops22h 50m

$603

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 10/28

5:20 pm-6:20 pm

1 stop17h 00m

Sofia

Fri 12/5

6:05 am-2:35 pm

1 stop17h 30m

$609

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Sat 8/23

7:50 pm-8:25 pm

1 stop15h 35m

Sofia

Sat 9/6

9:25 am-5:55 pm

1 stop17h 30m

$634

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Wed 10/8

9:40 am-5:50 pm

2 stops23h 10m

Sofia

Wed 10/22

6:15 am-3:35 pm

1 stop18h 20m

$650

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 9/30

9:36 am-3:20 pm

2 stops20h 44m

Sofia

Tue 10/7

8:00 am-4:35 pm

2 stops17h 35m

$890

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Mon 7/14

5:50 pm-10:05 am

1 stop31h 15m

Sofia

Tue 7/29

1:15 pm-4:20 pm

1 stop36h 05m

$929

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 9/2

6:35 pm-8:40 pm

1 stop17h 05m

Sofia

Wed 9/10

9:30 pm-4:25 pm

1 stop27h 55m

$3,845

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Tue 9/2

5:06 pm-1:30 pm

2 stops59h 24m

Sofia

Mon 9/8

8:00 pm-8:00 pm

2 stops33h 00m

$3,906

DenverSofia

DEN - SOF

DENSOF

Denver Intl

Wed 9/10

8:20 pm-11:00 pm

1 stop17h 40m

$515

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 12 results
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Best time to book a flight from Denver to Sofia

Have a flexible travel schedule? Discover the best time to fly to Sofia from Denver 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 Denver to Sofia

How far ahead should I book a flight from Denver to Sofia?

Use this chart to determine the optimal time to book a round-trip flight from Denver to Sofia. Price data was last updated on June 9, 2025.

The price you pay for your flight from Denver to Sofia may vary depending on when you book. For the best chance of a lower fare, look to book 48 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Denver to Sofia?

Currently, November is the cheapest month in which you can book a flight from Denver to Sofia (average of $632). Flying from Denver to Sofia in June is currently the most expensive (average of $1,203). 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 DEN to SOF?

Find hourly flight availability from Denver to Sofia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

It’s typically best to fly out from Denver to Sofia in the evening. Doing so could potentially save you 41% on the flight price compared to flying in the morning, which is usually more expensive.

Rainfall in Sofia by month

Plan your trip to Sofia by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Sofia ranges from 1.2 - 2.8 inches per month. June is typically the wettest month, when rainfall can reach 2.8 in. January is typically the driest time to visit Sofia when rainfall is around 1.2 in.

Temperature in Sofia by month

Plan your trip to Sofia by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Sofia, 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 68.0 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 Sofia

Get insights into the airlines that provide service to Sofia. 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 Sofia. Reviews last updated June 12, 2025.
Read reviews from past customers who have flown Austrian Airlines, SWISS and United Airlines from Denver to Sofia. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well
Austrian Airlines
7.6
Good
802 reviews
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well
SWISS
7.5
Good
1,623 reviews
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well
United Airlines
7.4
Good
8,790 reviews
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well
Turkish Airlines
7.3
Good
3,848 reviews
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well
American Airlines
7.2
Good
10,000 reviews
Austrian Airlines
7.6
Good
802 reviews

Entertainment

6.8

Crew

8.1

Overall

7.6

Comfort

7.3

Boarding

7.6

Food

6.8

Reviews

1 / 20
8.0
Excellent

Grant,Jun 2025

VIE - FRA

A delay was caused by computer malfunctions after we left the gate. It was handled well

Related info for your journey

Find useful and relevant information for your journey from Denver to Sofia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What are the cheapest airlines flying from Denver to Sofia round-trip?

    Our cheapest airline available from Denver to Sofia is United Airlines. Our recent data shows that you can find tickets from as low as $599 on this airline. Additional options worth looking into are Air Canada and Lufthansa, starting at $603 and $609 round-trip. United Airlines is currently priced 34% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Denver to Sofia one-way?

    The cheapest airline one-way is United Airlines, with whom users have recently found tickets for as low as $515. However, be on the lookout for offers from Air Canada and Lufthansa, as they are both options that can get you from Denver to Sofia for a low price.

  • Can I find deals for flights from Denver to Sofia that include hotel bookings?

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

  • How can I find direct flights from Denver to Sofia?

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

  • Can I find deals for business class flights from Denver to Sofia?

    Yes. Cheapflights offers flight deals from Denver to Sofia 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 Denver to Sofia?

    Currently, November is the cheapest month in which you can book a flight from Denver to Sofia (average of $632). Flying from Denver to Sofia in June is currently the most expensive (average of $1,203). 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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Alternative routes for Denver to Sofia

See prices for flight routes from nearby airports that may be better suited for you.
Grand Junction to Sofia flights

Top 3 airlines flying from Denver to Sofia

Discover the top 3 airlines that operate flights from Denver to Sofia. 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$530Average$723FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$653Average$864FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$715Average$1,154FlexibilityNo cancel feeOn-time76%

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