DEN - SOF

$345 Find Cheap Flights from Denver to Sofia - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to Sofia departing on 9/14. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Sofia

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Sofia, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Sofia, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$737
Typical prices: $1,175-$1,023
United Airlines
Mon 12/7Thu 12/10
DEN - SOF • 1 stop
Cheapest one-way
$345
Typical prices: $324-$424
Lufthansa
Mon 9/14
DEN - SOF • 1 stop
Top airlines
Cheapest • from $737 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Denver and Sofia. You'll need at least 1 connection.
Insights
Insights
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Insights
Top layover airports
Cheapest • Avg $769 (round-trip)
Shortest trip • 14h 46m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 25% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 22% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Sofia!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Denver to Sofia (DEN-SOF)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Denver to Sofia that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Denver to Sofia

Mon, Dec 7 - Thu, Dec 10
United Airlines Logo
8:20 pm - 10:45 pm
DEN
-
SOF
17h 25m
1 stop
United Airlines Logo
6:25 am - 1:40 pm
SOF
-
DEN
16h 15m
1 stop
$737United Airlines
Mon, Dec 7 - Thu, Dec 10
United Airlines Logo
4:15 pm - 6:20 pm
DEN
-
SOF
17h 05m
1 stop
United Airlines Logo
6:25 am - 8:27 pm
SOF
-
DEN
23h 02m
2 stops
$740United Airlines
Mon, Dec 7 - Thu, Dec 10
United Airlines Logo
4:15 pm - 6:20 pm
DEN
-
SOF
17h 05m
2 stops
United Airlines Logo
6:25 am - 5:46 pm
SOF
-
DEN
20h 21m
2 stops
$750United Airlines
Tue, Sep 8 - Thu, Sep 17
Turkish Airlines Logo
8:25 pm - 8:20 pm
DEN
-
SOF
14h 55m
1 stop
Turkish Airlines Logo
9:35 am - 6:25 pm
SOF
-
DEN
17h 50m
1 stop
$751Turkish Airlines
Thu, Nov 5 - Mon, Nov 9
Lufthansa Logo
4:15 pm - 6:20 pm
DEN
-
SOF
17h 05m
1 stop
Lufthansa Logo
1:55 pm - 2:30 pm
SOF
-
DEN
33h 35m
1 stop
$779Lufthansa
Thu, Nov 5 - Mon, Nov 9
United Airlines Logo
10:25 am - 1:15 pm
DEN
-
SOF
17h 50m
2 stops
United Airlines Logo
1:55 pm - 2:30 pm
SOF
-
DEN
33h 35m
1 stop
$804United Airlines
Sun, Sep 6 - Sat, Sep 12
Turkish Airlines Logo
8:25 pm - 3:00 pm
DEN
-
SOF
33h 35m
1 stop
Turkish Airlines Logo
3:50 pm - 6:25 pm
SOF
-
DEN
35h 35m
1 stop
$808Turkish Airlines
Thu, Sep 3 - Thu, Sep 17
United Airlines Logo
6:00 am - 12:10 pm
DEN
-
SOF
21h 10m
2 stops
United Airlines Logo
6:10 am - 1:45 pm
SOF
-
DEN
16h 35m
1 stop
$823United Airlines
Thu, Sep 3 - Thu, Sep 17
Multiple Airlines Logo
10:26 am - 2:00 pm
DEN
-
SOF
18h 34m
2 stops
Multiple Airlines Logo
7:00 am - 8:59 pm
SOF
-
DEN
22h 59m
2 stops
$829Multiple Airlines
Thu, Sep 3 - Thu, Sep 17
Lufthansa Logo
5:40 pm - 10:40 pm
DEN
-
SOF
20h 00m
1 stop
Lufthansa Logo
6:10 am - 1:45 pm
SOF
-
DEN
16h 35m
1 stop
$830Lufthansa
Booking Insights

KAYAK's insights & trends for Denver to Sofia flights

Get data-powered insights and trends into flights from Denver to Sofia to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Denver to Sofia?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Denver to Sofia departing in December.

What is the cheapest month to fly from Denver to Sofia?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Denver to Sofia, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Denver to Sofia is November, where tickets cost $596 (return) on average. On the other hand, the most expensive months are December and June, where the average cost of round-trip tickets is $1,026 and $982 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Denver to Sofia, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Denver to Sofia, you should book around 2 weeks before departure, which saves you about 25% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 14 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$345
Best time to beat the crowds but there is an average 3% increase in price.
Most popular time to fly with an average 28% increase in price.
Flight from Denver to Sofia

When to book flights from Denver to Sofia

Are your dates flexible? Find out the best times to travel from Denver to Sofia based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Denver to Sofia

  • What is the cheapest flight from Denver to Sofia?

    In the last 5 days, the lowest price for a flight from Denver to Sofia was $345 for a one-way ticket and $737 for a round-trip.

  • Do I need a passport to fly between Denver and Sofia?

    Yes, you'll most likely have to show a valid passport before boarding the plane in Denver and on arrival in Sofia.

  • Which aircraft models fly most regularly from Denver to Sofia?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Denver to Sofia?

    Star Alliance is the only airline alliance operating flights between Denver and Sofia.

  • Which is the best airline for flights from Denver to Sofia, Turkish Airlines or United Airlines?

    The two airlines most popular with KAYAK users for flights from Denver to Sofia are Turkish Airlines and United Airlines. With an average price for the route of $639 and an overall rating of 7.4, Turkish Airlines is the most popular choice. United Airlines is also a great choice for the route, with an average price of $983 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from Denver to Sofia?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Denver to Sofia.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Denver to Sofia?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Sofia from Denver is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Denver to Sofia?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Sofia with an airline and back to Denver with another airline. Booking your flights between Denver and SOF can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Denver to Sofia?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Sofia from Denver up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 3 airlines serving from Denver to Sofia

 
See real verified KAYAK customer reviews for airlines flying from Denver to Sofia. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Denver to Sofia? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
Turkish AirlinesOverall score based on 4409 reviews
7.8Crew
7.3Boarding
7.3Comfort
7.5Entertainment
7.5Food
Airline reviews

Entertainment system is okay, flight attendants were ok. Leg space very narrow, I couldn’t get what I wanted to eat, dinner nor breakfast.

6.0 GoodAnonymous, Jun 2026
SFO - IST
Read more Turkish Airlines reviews

Entertainment system is okay, flight attendants were ok. Leg space very narrow, I couldn’t get what I wanted to eat, dinner nor breakfast.

Excellent experience with business class area. Staff was attentive and food was amazing. Only one bathroom for business class which was logistically difficult for the staff while preparing meals. Need to offer fluids with meals. I did not get enough water to drink. But overall I rate it 5 star.

On time, great food, good drink selection! Only down was alcohol-free lounge. Lufthansa had a much better offering!

Be honest of what you sell: This was sold as Business Class on all three legs, while the JetBlue plane didn't even have business class seats, and wanted $164 for extra legroom seats.

Seat assignments for family traveling with 2 children. Loud crowd during sleep time

It was crowded… the bathrooms dirty and smelly. The seats have been made even smaller.

delayed to take off from detroit by 3 hours lost baggage in istanbul and now in venice without baggage

Seats were very tight with poor legroom - and I am average height. During the 12 hour flight, tiny paper cups of drinks we're only offered during the super and breakfast services, with the crew nowhere to be seen in between. One of the bathrooms was out of order, leading to long lines waiting to use the remaining two available to the economy class passengers.

short flight but we still got a very nice lunch and the crew did an excellent job in taking care of us

For that price on Business class, I expected to have the pod seats. These were configured as 2/3/2 and my seat mate talked half the flight with a friend across the isle, loudly. Very uncouth.

Destroyed my suitcase. Tired of talking about it. Cancelling my unite mileage plus account.

New plane was lovely. Crew customer service is always lax but expected. Kraft on time and arrived safely.

It was a short flight so I was expecting too much

Had a one hour delay due to mechanical issue. I didn’t think I’d be able to make my connecting flight, but they waited for me and greeted me when I arrived to help things run smooth.

O’hsre taxi and deboarding took 40 minutes. Needed 20 minutes extra time between connecting flights to avoid running through terminal.

Was great in general, try to respect time and excuses when slight changes have been made, appreciated!

Really hard landing... as in slammed into the runway then hit the brakes really hard ...

Putting people that close to the bathroom, where you have to look into the bathroom as people are exiting and entering was not great and the smell was also not great. I know the airlines are desperate for more chairs, but that seat is a crime.

Every staff member was professional, friendly and courteous. The pizza twist was ok. It was warm but too much dough.

one staffer was frustrated (it happen); the flight was late and the pilot mentioned they'll make amend but the snacks were the same, other than that the aircraft was clean and everything went smooth, no complaints

They messed up my seat so I didn’t get the one I paid for

Put me on standby; flight was late; missed my connecting flight; disaster

Flight attendants were fine, seats a bit hard but I use a cushion for extra support. The only issue was it was a bit too cool and I needed to ask for and received and extra blanket. I survived!!!

Very few things and/or people are excellent. It was very good.

Extremely uncomfortable seats. Experience was like a Frontier Airlines flight. Would not fly it again.

Very, very tight legroom. They must’ve jammed in an additional few rows of seat seating. Denver to Munich was the least legroom I’ve ever had on any flight, let alone a multi hour international journey. I will not take that flight again.

In my first flight with Air Canada we sat in the plane for 4:00pm to 6:30pm. Finally we were asked to get off the plane and we were told the flight was cancelled after 7:00pm There was o clear explanation of what was the problem. I was booked without my permission on a Delta Flight at 7:30pm that was leaving at 8:00pm and I still had to go get my luggage(my final destination was Rome with one stop in Toronto. The luggage claim for Canada was closed so had to return to finally get it on the luggage belt.. Of course I missed the Delta flight and all the next day flights were booked. I also lost what I paid for my stay in Rome because I did nt cancel in time. A complete nightmare.

Good food, overall very comfy. The flight was full so obviously not optimal, but it is what it is.

Perfect airline, super friendly, great service, tasty food. Would fly again.

Parents with permanently crying baby on board. Neither parents nor crew did anything to calm the baby. The food was extremely disappointing. Seafood stew was very, very small! Not even appetizer size! Seat had a gap in the back. Had to use a pillow to fill it.

Everything you need to know for your flight from Denver to Sofia

Information on your arrival and departure airports