DEN - SOF

$500 Find Cheap Flights from Denver to Sofia

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 12/5. 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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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

Sat, Mar 21 - Sat, Mar 28
Turkish Airlines Logo
8:20 pm - 8:45 amDEN-SOF
28h 25m1 stop
Turkish Airlines Logo
9:35 am - 6:35 pmSOF-DEN
17h 00m1 stop
$581Turkish Airlines
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Mon, Mar 23 - Mon, Mar 30
United Airlines Logo
5:20 pm - 6:20 pmDEN-SOF
17h 00m1 stop
United Airlines Logo
12:50 pm - 2:20 pmSOF-DEN
34h 30m1 stop
$582United Airlines
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Sun, Mar 22 - Mon, Mar 30
United Airlines Logo
6:00 am - 1:00 pmDEN-SOF
23h 00m2 stops
United Airlines Logo
12:50 pm - 2:20 pmSOF-DEN
34h 30m1 stop
$587United Airlines
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Thu, Apr 9 - Thu, Apr 23
Turkish Airlines Logo
8:25 pm - 8:15 pmDEN-SOF
14h 50m1 stop
Turkish Airlines Logo
9:35 am - 6:20 pmSOF-DEN
17h 45m1 stop
$593Turkish Airlines
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Sat, Mar 21 - Mon, Mar 30
Lufthansa Logo
5:54 pm - 1:35 pmDEN-SOF
35h 41m2 stops
Lufthansa Logo
12:50 pm - 2:20 pmSOF-DEN
34h 30m1 stop
$616Lufthansa
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Thu, Mar 19 - Mon, Mar 30
British Airways Logo
6:25 pm - 11:15 amDEN-SOF
32h 50m1 stop
British Airways Logo
8:00 pm - 4:35 pmSOF-DEN
29h 35m1 stop
$618British Airways
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Mon, Mar 23 - Mon, Mar 30
Lufthansa Logo
5:54 pm - 6:20 pmDEN-SOF
16h 26m2 stops
Lufthansa Logo
6:40 pm - 3:56 pmSOF-DEN
30h 16m2 stops
$620Lufthansa
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Thu, Apr 9 - Thu, Apr 23
Air Canada Logo
11:05 am - 6:40 pmDEN-SOF
22h 35m2 stops
Air Canada Logo
6:10 am - 8:00 pmSOF-DEN
46h 50m2 stops
$635Air Canada
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Sun, Mar 22 - Sat, Mar 28
British Airways Logo
6:25 pm - 4:20 pmDEN-SOF
13h 55m1 stop
British Airways Logo
12:05 pm - 4:35 pmSOF-DEN
36h 30m1 stop
$693British Airways
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Thu, Mar 19 - Sun, Mar 29
Air Canada Logo
11:15 am - 1:50 pmDEN-SOF
18h 35m2 stops
Air Canada Logo
1:55 pm - 12:01 pmSOF-DEN
31h 06m2 stops
$698Air Canada
Find Deal

Everything you should know

Top airlines
Turkish Airlines
Cheapest • from $581 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to book
2 weeks
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 29% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
April
Cheapest • 38% price drop
May
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Cheapest round-trip
$581
Overall average: $661
Turkish Airlines
Sat 3/21Sat 3/28
DEN - SOF • 1 stop
Cheapest one-way
$500
Typical prices: $559-$664
Lufthansa
Fri 12/5
DEN - SOF • 1 stop
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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!
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.

What’s the cheapest day of the week to fly from Denver to Sofia?

The average price of all round-trip flights from Denver to Sofia clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Sofia on a Thursday, as we generally find the cheapest rates on that day for this route. On the other hand, Saturday is the most expensive day to fly from Denver to Sofia. For your return ticket, we recommend flying on a Friday and avoiding Thursdays for the best deals.

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 April, where tickets cost $535 (return) on average. On the other hand, the most expensive months are May and July, where the average cost of round-trip tickets is $1,282 and $1,263 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 29% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 8 weeks before departure.

Good to know

Low seasonDecember
Cheapest flight$500
Best time to beat the crowds but there is an average 33% increase in price.
Most popular time to fly with an average 48% 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 3 days, the lowest price for a flight from Denver to Sofia was $500 for a one-way ticket and $581 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, United Airlines or Turkish Airlines?

    The two airlines most popular with KAYAK users for flights from Denver to Sofia are United Airlines and Turkish Airlines. With an average price for the route of $870 and an overall rating of 7.4, United Airlines is the most popular choice. Turkish Airlines is also a great choice for the route, with an average price of $628 and an overall rating of 7.3.

  • 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
United AirlinesOverall score based on 8998 reviews
7.1Entertainment
7.7Boarding
6.6Food
8.1Crew
7.3Comfort
Airline reviews

Great smooth flight. Had a seating change, but that was an improvement. Thanks United Airways Crew.

10.0 ExcellentBen, Oct 2025DEN - PVR
Read more United Airlines reviews

Great smooth flight. Had a seating change, but that was an improvement. Thanks United Airways Crew.

Flight was good but there are way to many announcements for credit cards etc.

Crew seemed a bit cranky. No seatback screens. But boarding was efficient and on time and we arrived early.

See previous note about the passenger in Denver who threw my husband's bag out of the overhead bin in order to maker room for his own. And the flight attendant back up the new passenger.

Terrible. They wouldn't allow me on my flight on the 14th..

Ridiculous boarding. Enter the gate, walk down a staircase with bags, exit a building, get on a crowded bus, dropped off a few meters away from the aircraft, walk with bags to another set of stairs to board the aircraft. And all that during a pouring down rain, and with children. Ridiculous!!!

Impressed with the service despite turbulence because of the weather. Both flights arrived before their scheduled times.

Great experience…left a bit behind schedule but made up fir that in the air and landed 10 minutes early 😁

The seat and leg room was not good. The food and beverage service was good.

For economy, it was very good. Staff was great, they even let some of us change seats for more leg room... Put an empty seat between us which was fantastic for a 12hr flight. Onboard entertainment was excellent, I think over 200 choices of movies/tv/etc The bad was the barely/nonfunctional wifi that cost either $16.99 or 1700 miles (full flight). It was atrocious... Definitely the worst of the last 3 long haul major airlines I was on the last few months.

My flight was canceled 1 minute before boarding. The customer service was owful, no one could tell us what was going happened. I spent 30hrs instead of 15 from Washington DC to Brussels. No apologie or help

Boeing 777 is a bad choice for a such a long flight.

The staff at IST airport could have been more helpful. Too much wasted time and the plane from IST to KHI was just horrible. The plane was not clean and smelled bad!

This is my 2nd time with the Turkish airline. Would definitely recommend. In stability we connected to Indiago would not recommend, very cramped seating. No inflight entertainment..service was inferior.

I wouldn't know what the flight was like. AI canceled my flight reservation!! There's no way to speak to an actual human to fix the issue! NEVER AGAIN! ALWAYS BOOK YOUR FLIGHT DIRECTLY WITH THE AIRLINE NEVER GO THROUGH KAYAK OR JUSTFLY.COM!!

Paying extra for premium seats was wasted. Turkish Airlines takes 2 seats for bassinet. The lady next to me had a baby with bassinet Bassinet was in front of my seat

Rude staff. I would avoid using the word racist but definitely partially or discriminatory. My 72 yrs old mother who is also disabled was traveling on this flight. She was the second passenger boarded to the plane. The First elderly couple ahead of my mother were allowed to use the airplane bathroom but my mother was denied entry stating it was for safety reasons. My mother objected the the couple in front of her were allowed but hostess still stated that due to the flight safety reasons she can’t use it. Even my mother explained that he is using blood pressure medication that’s why she have to use the restroom frequently but the crew continued arguing her. At one point the Mae attendent even suggested that if that’s the case my mother can urinate in her seat. The level of disrespect against an elderly lady is beyond my comprehension. This matter will be taken to the social media to shame the employees involved.

my experience was great with Turkish airlines . the problem i encountered was with kayak booking. When I booked . it showed that im allowed a bag . and when I got to the airport, i had to pay $165 for one bag.

Not up to Business Class standards. Two of the three toilets were out of order. The hostesses were aware and didn’t show any responsible act to do something. Food quality was not what we expect from Turkish hospitality. Overall we were not impressed and disappointed.

During mid flight, try to get a flight attendant to help I couldn’t find one Otherwise, everything was perfect

I booked extra leg room, due to seat neighbor i now consider extra shoulder and arm room as well. Seems like the seats shrink in width now The crew was very friendly and professional ( 100%). Food was good not great, breakfast was bad, a dry slice of bread would have been better. Facilities clean.

Luggage transfer in Chicago was not performed in time. I received my luggage at my destination two days later.

love the crews and my only problem was the delay at Frankfurt was very bad. I have travelled with Lufthansa for over 30 years now and this was cost me some planned business appointment

The flight delay made the connection a bit tight but that's outside the flight crew's control.

We just made it to our connecting flight. A long, long speed walk!

We didn't get the coffee with breakfast in the morning.. 30 mins lazer I asked flight attendant why don't we get coffee now at least.. after the breakfast..she said that captain announced possible turbulences fee minutes ago, which didn't ecplain why we didn't get it with the breakfast..breakfast was very poor btw..just little pastry which you can eat in 4 little bites. Turbulences fortunately didn't even happen.. but we didn't get that more than necessary coffee in the morning after the night flight with very poor sleep.. They just served breakfast 1 hour afzer we took off..at like 11 PM.. that doesn't make sense at all.. Also, flight attendants weren't very nice..they looked like they're not happy with their job.. :/

Lufthansa still has a good level of quality compared to US airlines, especially with respect to (1) food quality - actually tasty, (2) good French red wine - free, (3) good movie selection. Also my ticket price includes 1 free check-in luggage, while some other budget airlines sneak in an extra $150 for a checkin.

I think they overbooked Frankfurt to New York and bumped me off. This changed my return travel I arrived home about 4 hours late. Almost 24 total travel time Totally unacceptable Would not travel with United

We were moved twice on flights to the point we weren’t even on Lufthansa anymore. We had to fly united. Lost paid extra leg room twice. To top it all off we’re forced to pay $375 and $275, respectively for you luggage that was considered sports luggage. We were told it would be Lufthansa fares l, from the united desk, AND WE DIDN'T EVEN HAVE A LUFTHANSA FLIGHT! I’ll be calling once my trip is over on October 7th to all airlines and Kayak. This was ridiculous!

Everything went smoothly and the staff was very kind. I’m glad I purchased the extra leg room for my long flight; it was totally worth it. We were served 2 meals for a 9 hour flight which I was not expecting and they were very tasty. I appreciated them being vegetarian. Customs line in Munich was long; I had a choice to have a 1 hr 40 min layover or 2 hr 40 min layover; I took the longer layover which I was thankful for because my flight was delayed 30 minutes and there’s a good chance I would have missed my connecting flight. This was my very first international flight and I would fly Discover again without hesitation. Thank you for taking good care of me!

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

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