STL - SOF

$732 Find Cheap Flights from St. Louis to Sofia

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Sofia departing on 9/5. 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

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 St. Louis 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 St. Louis to Sofia, as well as popular online travel agencies
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Flights Deals

Cheap Flights from St. Louis to Sofia (STL-SOF)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis 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 St. Louis to Sofia

Fri, Sep 5 - Fri, Sep 19
United Airlines Logo
1:30 pm - 10:50 pmSTL-SOF
25h 20m2 stops
United Airlines Logo
6:15 am - 1:30 pmSOF-STL
15h 15m1 stop
$732United Airlines
Find Deal
Fri, Sep 5 - Fri, Sep 19
 Logo
5:30 pm - 10:50 pmSTL-SOF
21h 20m2 stops
 Logo
6:15 am - 7:57 pmSOF-STL
21h 42m2 stops
Sat, Sep 27 - Sun, Oct 19
 Logo
4:05 pm - 10:50 pmSTL-SOF
46h 45m2 stops
 Logo
6:20 am - 7:38 pmSOF-STL
45h 18m2 stops
Fri, Sep 5 - Fri, Sep 19
Lufthansa Logo
3:30 pm - 1:25 pmSTL-SOF
13h 55m1 stop
Lufthansa Logo
6:15 am - 1:30 pmSOF-STL
15h 15m1 stop
$883Lufthansa
Find Deal
Sat, Sep 27 - Sun, Oct 19
Lufthansa Logo
5:28 pm - 5:50 pmSTL-SOF
40h 22m2 stops
Lufthansa Logo
6:20 am - 1:30 pmSOF-STL
15h 10m1 stop
$885Lufthansa
Find Deal
Thu, Jul 10 - Sun, Aug 10
Lufthansa Logo
5:30 pm - 11:00 pmSTL-SOF
21h 30m2 stops
Lufthansa Logo
7:25 pm - 3:47 pmSOF-STL
28h 22m2 stops
$1,181Lufthansa
Find Deal
Thu, Jul 10 - Sun, Aug 10
Lufthansa Logo
5:30 pm - 11:00 pmSTL-SOF
21h 30m2 stops
Lufthansa Logo
6:20 am - 1:30 pmSOF-STL
15h 10m1 stop
$1,306Lufthansa
Find Deal
Sat, Sep 27 - Sun, Oct 19
 Logo
1:30 pm - 2:55 amSTL-SOF
29h 25m3 stops
 Logo
8:00 am - 7:38 pmSOF-STL
19h 38m2 stops
$1,337
Find Deal
Thu, Jul 10 - Sun, Aug 10
 Logo
5:00 am - 5:10 pmSTL-SOF
28h 10m3 stops
 Logo
12:45 pm - 8:00 pmSOF-STL
39h 15m2 stops
$1,494
Find Deal
Sat, Sep 27 - Sun, Oct 19
 Logo
1:00 pm - 8:35 amSTL-SOF
35h 35m3 stops
 Logo
9:25 am - 7:49 amSOF-STL
30h 24m3 stops
$1,509
Find Deal
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KAYAK's insights & trends for St. Louis to Sofia flights

Get data-powered insights and trends into flights from St. Louis 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 St. Louis to Sofia?

The average price of all round-trip flights from St. Louis 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 Saturday, as we generally find the cheapest rates on that day for this route. On the other hand, Friday is the most expensive day to fly from St. Louis to Sofia. For your return ticket, we recommend flying on a Wednesday and avoiding Tuesdays for the best deals.

What is the cheapest month to fly from St. Louis to Sofia?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis 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 St. Louis to Sofia is February, where tickets cost $640 (return) on average. On the other hand, the most expensive months are June and December, where the average cost of round-trip tickets is $1,434 and $1,307 respectively.

How far in advance should I book a flight from St. Louis 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 St. Louis 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 St. Louis to Sofia, you should book around 5 weeks before departure. For the absolute cheapest price, our data suggests you should book 22 weeks before departure.

Good to know

Low seasonJanuary
High seasonJuly
Cheapest flight$732
Best time to beat the crowds with an average 28% drop in price.
Most popular time to fly and prices are also 6% lower on average.
Flight from St. Louis to Sofia

When to book flights from St. Louis to Sofia

Are your dates flexible? Find out the best times to travel from St. Louis 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 St. Louis to Sofia

  • What is the cheapest flight from St. Louis to Sofia?

    In the last 3 days, the lowest price for a flight from St. Louis to Sofia was $732 for a round-trip ticket.

  • Do I need a passport to fly between St. Louis and Sofia?

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

  • Which aircraft models fly most regularly from St. Louis to Sofia?

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

  • Which airline alliances offer flights from St. Louis to Sofia?

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

  • Which is the best airline for flights from St. Louis to Sofia, United Airlines or Lufthansa?

    The two airlines most popular with KAYAK users for flights from St. Louis to Sofia are United Airlines and Lufthansa. With an average price for the route of $966 and an overall rating of 7.4, United Airlines is the most popular choice. Lufthansa is also a great choice for the route, with an average price of $1,020 and an overall rating of 6.7.

  • How does KAYAK find such low prices on flights from St. Louis 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 St. Louis to Sofia.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Sofia from St. Louis 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 St. Louis 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 St. Louis with another airline. Booking your flights between St. Louis 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 St. Louis 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 St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top airlines flying from St. Louis to Sofia

 
See real verified KAYAK customer reviews for airlines flying from St. Louis 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 St. Louis 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 8790 reviews
6.6Food
7.0Entertainment
7.7Boarding
7.3Comfort
8.1Crew
Airline reviews

it was so bad. I tried to board my flight from vancouver to saskatoon. And to my surprise they did not board me cause the flight was changed and no email was send to me. and on my boarding pass which i got from seattle says different flight. I did not knew anyone from Vancouver, air canada crew was rude, i asked for today flight but they were rude and i had early morning dental appointment in saskatoon. I was so much in pain and my whole day is wasted today. and i suffered alot. They did provide me hotel but they did not provide me any food. I am really really disappointed first time had so bad experience with air canada. I may think twice to book it again. If i can get any reply or any composition that would be great. Thanks

2.0 MediocreAnonymous, Jun 2025LAX - SEA
Read more United Airlines reviews

it was so bad. I tried to board my flight from vancouver to saskatoon. And to my surprise they did not board me cause the flight was changed and no email was send to me. and on my boarding pass which i got from seattle says different flight. I did not knew anyone from Vancouver, air canada crew was rude, i asked for today flight but they were rude and i had early morning dental appointment in saskatoon. I was so much in pain and my whole day is wasted today. and i suffered alot. They did provide me hotel but they did not provide me any food. I am really really disappointed first time had so bad experience with air canada. I may think twice to book it again. If i can get any reply or any composition that would be great. Thanks

It was fine, definitely older planes with no charging or anything. There’s no entertainment set up on board, but it is nice that they allow you to access the in flight entertainment from your phone without having to pay for the Wi-Fi and they do offer free texting.

Terrible. Out flight was delayed for 21 (twenty one) hours. United is a joke.

Boarding was mayhem. Late boarding by 15 minutes because of lack of staff (missing 1 flight attendant. We had to wait for an arrival of another plane before we could board). Flight was a little rough, but cannot blame on airlines.

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

Very comfortable (upgraded to business class). The audio on my screen didn’t work, but I managed to play the audio through my phone while watching the screen.

The food was the worst I’ve had on any flight I’ve ever been on.

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

I was supposed to be on business class at first class from Denver back to Miami due to weather changes. I missed my connection and it’s put on a flight to Fort Lauderdale. Instead of honoring my business class/1st class ticket, they put me in coach, but there were two first class seats open. I think it’s absolutely disgusting that I paid for first class $1300 ticket and they put me in economy and they had to open seats available and I have still not been refunded the difference. I ended up having to eat a snack box instead of the meal I was supposed to get and did not get home till 2 AM so I think that’s a little pathetic that I had to live off crackers for dinner And my poor dog ate some cheese and salami. Oh yes, apparently when they switched me to the new flight they forgot to mention I had a service dog

Excellent service despite turbulence during the flight. Flight attendants were remarkable!

Flight was 1.5 hours late to depart so changed flights to Swiss Air.

The United Airlines crew that operated this flight was subpar. They didn’t

Very small and uncomfortable seats, Hard to hear entertainment system sound. Horrible food. Staff doesn't care much about the passengers. 2nd time they didn't give me my vegetarian meal. They asked me regular food with meat. The airline and staff was from United airlines.

Checkin took along timen only.few angents available at.checkin desk. Customer support over phone no existence

At baggage claim, I was given the wrong printed ticket. The ticket belonged to another passenger for a different flight — to Zurich instead of Frankfurt (layover). I was even allowed to pass security, and when I asked the Lufthansa employee if I was on the correct flight, and why it was changed. The employee said everything was correct and I should board. When I got on the plane, there was someone in my seat, and the crew on the plane finally realized that I was on the wrong plane. When I got off the plane, nobody was willing to help, and the security refused to provide my original printed ticket. That was until I showed them that I took a photo of the ticket; once they realized I had photographic evidence, they were suddenly ready to help me. The Lufthansa employee began communicating with other airlines and found a flight that would take me to my destination via Polish Airlines. I was required to once again go through security, re-check my bag, and once again pay for my checked bag and weight overage fees. This experience was incredibly stressful and very frustrating, as you can imagine. A Lufthansa employee told me I would be eligible for a refund. Please tell me what steps I need to take in order to make that happen. Thank you!

The row of seats were so cramped it was difficult to get in and out of your seat. I even upgraded. A long flight and sad accommodations 😵‍💫 the shorter flight was very comfortable and the seating was spacious

I bought a ticket and paid for for our luggage but I had to pay for my luggage again. I’m so disappointed! We had a 30 min delay and because of that we missed our connecting flight and were told that we would be on the next flight (9am flight ) but we were landed we were booked at 12pm flight. I had a little baby w me, it was very stressful. I begged to leave at 10 am at least. I was emailed that we get a voucher but they didn’t work when we were at a breakfast store. I’ve been always happy w Lufthansa but this time was awful.

Good service … bus transfer upon arrival from plane to terminal: atrocious!!!

helpful and friendly. The Lufthanza people I dealt with before my holiday were so unhelpful by comparison.

We had a 1 1/2 hour delay before we left Denver. When we arrive to Frankfort, they didn’t announce that people with connecting flights to exit the plane first. My next flight was already boarding when we we taxiing in to the gate. I waited another 10 minutes to get off the plane. I had to run to catch my next flight. I mean run! I made it with one minute to spare, but my luggage did not. My luggage came two hours later on a different flight.

Everything you need to know for your flight from St. Louis to Sofia

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