$339 Cheap Flights from Denver (DEN) to Sofia (SOF)

View $339 flight on Sun, Oct 25, 2026Opens in a new window

Popular airlines from Denver Intl. Airport (DEN) to Sofia Airport (SOF)

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Cheap Flights from Denver to Sofia (DEN-SOF)

Prices were available within the past 7 days and start at $339 for one-way flights and $737 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Lufthansa
Sun, Apr 11 - Wed, Apr 21
DEN
Denver
SOF
Sofia
$737 Roundtrip, found 4 days ago
$737
Roundtrip
found 4 days ago
Select Lufthansa flight, departing Sun, Apr 11 from Denver to Sofia, returning Wed, Apr 21, priced at $737 found 4 days ago
United
Sun, Apr 11 - Wed, Apr 21
DEN
Denver
SOF
Sofia
$737 Roundtrip, found 4 days ago
$737
Roundtrip
found 4 days ago
Select United flight, departing Sun, Apr 11 from Denver to Sofia, returning Wed, Apr 21, priced at $737 found 4 days ago
Lufthansa
Mon, Nov 9 - Tue, Mar 9
DEN
Denver
SOF
Sofia
$738 Roundtrip, found 1 day ago
$738
Roundtrip
found 1 day ago
Select Lufthansa flight, departing Mon, Nov 9 from Denver to Sofia, returning Tue, Mar 9, priced at $738 found 1 day ago
Lufthansa
Mon, Nov 9 - Tue, Mar 9
DEN
Denver
SOF
Sofia
$739 Roundtrip, found 1 day ago
$739
Roundtrip
found 1 day ago
Select Lufthansa flight, departing Mon, Nov 9 from Denver to Sofia, returning Tue, Mar 9, priced at $739 found 1 day ago
British Airways
Sun, Apr 11 - Wed, Apr 21
DEN
Denver
SOF
Sofia
$740 Roundtrip, found 4 days ago
$740
Roundtrip
found 4 days ago
Select British Airways flight, departing Sun, Apr 11 from Denver to Sofia, returning Wed, Apr 21, priced at $740 found 4 days ago
Lufthansa
Sun, Apr 11 - Wed, Apr 21
DEN
Denver
SOF
Sofia
$741 Roundtrip, found 4 days ago
$741
Roundtrip
found 4 days ago
Select Lufthansa flight, departing Sun, Apr 11 from Denver to Sofia, returning Wed, Apr 21, priced at $741 found 4 days ago
Air Canada
Mon, Nov 9 - Tue, Mar 9
DEN
Denver
SOF
Sofia
$741 Roundtrip, found 1 day ago
$741
Roundtrip
found 1 day ago
Select Air Canada flight, departing Mon, Nov 9 from Denver to Sofia, returning Tue, Mar 9, priced at $741 found 1 day ago
Air Canada
Mon, Dec 7 - Thu, Dec 10
DEN
Denver
SOF
Sofia
$742 Roundtrip, found 5 days ago
$742
Roundtrip
found 5 days ago
Select Air Canada flight, departing Mon, Dec 7 from Denver to Sofia, returning Thu, Dec 10, priced at $742 found 5 days ago
United
Tue, Dec 1 - Tue, Dec 8
DEN
Denver
SOF
Sofia
$743 Roundtrip, found 5 days ago
$743
Roundtrip
found 5 days ago
Select United flight, departing Tue, Dec 1 from Denver to Sofia, returning Tue, Dec 8, priced at $743 found 5 days ago
Austrian Airlines
Sun, Apr 11 - Wed, Apr 21
DEN
Denver
SOF
Sofia
$794 Roundtrip, found 4 days ago
$794
Roundtrip
found 4 days ago
Select Austrian Airlines flight, departing Sun, Apr 11 from Denver to Sofia, returning Wed, Apr 21, priced at $794 found 4 days ago

Alternative airports near Sofia

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Sofia Airport SOF. Cheapest and Closest option available. Average driving time to city center is 11 minutes. Flights from $1,271
SOF
Sofia Airport
CheapestClosest
Average driving time to city center11 min
Flights from $1,271

What you need to know for your flight from Denver Intl. to Sofia

Denver (DEN) to Sofia (SOF) at a glance

Choose from a range of airlines offering flights from Denver (DEN) to Sofia (SOF) on this long-haul international route. Evaluate options from full-service carriers to discover the itinerary that aligns with your budget, schedule, and travel plans as you uncover the iconic sights and neighborhoods of Sofia. Here, you’ll find essential details for flights departing from Denver International Airport (DEN) to Sofia Airport (SOF).

  • Fastest flight duration: around 11h 45m in-flight, plus roughly 2h 30m layover with one stop
  • Route distance: roughly 5,900 miles (9,500 km)
  • Flights per week: around 7 departures on average
  • Typical fares (one-way): economy tickets often range from $305–$820, depending on seasonality and how far ahead you book

Flights from Denver International Airport (DEN) to Sofia Airport (SOF)

Based on the latest traveler bookings, here are the top airlines flying from Denver to Sofia, commonly selected for one-stop and multi-stop journeys. Popular layover options include Istanbul Airport (IST) with a layover of about 2 hours and 15 minutes, Frankfurt International Airport (FRA) at approximately 3 hours and 15 minutes, and Franz Josef Strauss International Airport (MUC) with a 1 hour and 45 minutes layover. These choices allow you to balance price, total travel time, and cabin class for the ideal itinerary.

  • United: As a full-service airline, United provides one-stop service with one-way ticket prices generally between $350 and $910. It represents about 57% of departures on this route, featuring an in-flight duration of 11 hours and 45 minutes, with a total travel time of approximately 14 hours and 45 minutes, including layover time.
  • Turkish Airlines: This full-service carrier also offers one-stop flights, with one-way fares typically priced from $305 to $530. It accounts for around 24% of the departures on this route, with a flight time of 11 hours and 45 minutes and a total journey duration of about 14 hours and 45 minutes, factoring in the layover.
  • Lufthansa: Another full-service option, Lufthansa provides one-stop service, with one-way fares ranging from $305 to $670. It holds approximately 12% of the departures on this route, with an in-flight time of 11 hours and 45 minutes and a total travel time of nearly 14 hours and 45 minutes, including layover.

Alternative route from Denver (DEN) to Sofia (SOF)

  • Colorado Springs to Sofia (COS-SOF): Located approximately 73 miles from Denver International Airport (DEN), Colorado Springs Airport (COS) serves as a key access point for international travelers.

How to find the best prices for flights from Denver (DEN) to Sofia (SOF)

Getting some of the best deals on flights from Denver to Sofia is all about timing and flexibility. Here are some key tips to help you save:

  1. Best times to book and fly: cheaper fares are often found when booking within two weeks, although most travelers tend to book at least two months in advance. Departures in the afternoon (12 PM to 6 PM) usually offer lower prices, while evening flights (6 PM to 12 AM) are the most popular. Additionally, flying on Wednesday typically results in cheaper rates, whereas Friday is the busiest travel day.
  2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
  3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
  4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
  6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Sofia Airport from Denver International Airport

Sofia welcomes travelers from Denver with a range of transport options based on price, convenience, and proximity. Here's how to reach Sofia efficiently:

  • Hotel transfer: Transfers offer a convenient way to reach your hotel in Sofia, with private rides that can be arranged in advance.
  • Car rental: Renting a car from Sofia Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Sofia Airport on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
  • Public transportation: From Sofia Airport, travelers will find Sofia Airport Terminal 2 Station, a metro station, about 0.7 miles away by car, while Sofia Seaport, a seaport, is approximately 4.6 miles from the airport, and Sofia Central Station, a train station, is located about 5 miles away by car, providing convenient access to various transport options.

Frequently asked questions

How much does a flight from Denver, CO (DEN-Denver Intl.) to Sofia (SOF) cost?
You can find cheap one-way flights from $339 and cheap return flights from $737 Denver, CO (DEN-Denver Intl.) to Sofia (SOF) with Expedia. One-way flights typically cost between $347 and $5562, and return flights often range between $830 and $6139. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Denver, CO (DEN-Denver Intl.) to Sofia (SOF) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
The cheapest month to fly from DEN to SOF is April when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
Enter DEN to SOF and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
Iberia is one of the cheapest airlines offering connecting flights from Denver (DEN) to Sofia (SOF) with a layover in O'Hare Intl. (ORD), starting from around $767. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
To find a cheap flight from Denver, CO (DEN-Denver Intl.) to Sofia (SOF), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
What is the earliest flight from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
Sort flights by "Departure (earliest)" on Expedia to find the earliest flight from DEN to SOF. To compare more early flights, use the "Early Morning" and "Morning" filters in your search.
What are the most popular departure times for flights from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
The most popular departure times for flights from Denver, CO (DEN-Denver Intl.) to Sofia (SOF) are in the late afternoon, from 3pm to 6pm. About 32% of passengers prefer this time window. Many major carriers, including United Airlines and Lufthansa, offer flights during this window. This timing works well because it allows you to enjoy your day in Denver before heading off on your journey.
How long does it take to fly from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
Flights from DEN to SOF with one stop typically take around 17 hours 30 minutes, covering approximately 5,876 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
Business class seats are offered on the DEN to SOF route. Airlines that offer business class service on this route include:

  • Lufthansa
  • British Airways
  • Icelandair
  • Air Canada
  • Turkish Airlines
  • United Airlines
  • Delta Air Lines
  • Edelweiss Air
  • American Airlines

First class is available with Lufthansa.
How do I earn miles on a Denver, CO (DEN-Denver Intl.) to Sofia (SOF) flight with Expedia?
It's easy to earn miles on a Denver, CO (DEN-Denver Intl.) to Sofia (SOF) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
Is it cheaper to buy a plane ticket from Denver, CO (DEN-Denver Intl.) to Sofia (SOF) at the last minute?
Typically, booking a last minute flight from Denver, CO (DEN-Denver Intl.) to Sofia (SOF) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Denver, CO (DEN-Denver Intl.) to Sofia (SOF) flight and hotel package?
Securing a Denver, CO (DEN-Denver Intl.) to Sofia (SOF) Sofia Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Denver, CO (DEN-Denver Intl.) to Sofia (SOF)?
If you booked your Denver, CO (DEN-Denver Intl.) to Sofia (SOF) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Denver Intl.
Destination airport
Sofia
Roundtrip price
$737
Distance
5875 mi

Book with confidence

Denver to Sofia Flights

The cheapest times to fly from Denver to Sofia

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Denver to Sofia are during the month of April. You can find some of the cheapest flights from Denver to Sofia with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Denver to Sofia

Sunday is one of the best days to book for cheap flights from Denver to Sofia: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Denver to Sofia

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Denver to Sofia in 2026. You can also book with separate airlines for your outbound and return journeys, from $339 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Denver to Sofia flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Denver to Sofia airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Denver to Sofia Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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