PHL - SOF

$493 Find Cheap Flights from Philadelphia 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 Philadelphia to Sofia departing on 5/24. 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 Philadelphia 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 Philadelphia to Sofia, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$738
Typical prices: $740-$664
United Airlines
Wed 9/9Wed 9/16
PHL - SOF • 2 stops
Cheapest one-way
$493
Multiple Airlines
Sun 5/24
PHL - SOF • 3 stops
Top airlines
Cheapest • from $738 (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 Philadelphia and Sofia. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 59% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
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 Philadelphia to Sofia (PHL-SOF)

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

Wed, Sep 9 - Wed, Sep 16
United Airlines Logo
10:28 am - 6:40 pm
PHL
-
SOF
25h 12m
2 stops
United Airlines Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$738United Airlines
Tue, Sep 8 - Wed, Sep 16
Multiple Airlines Logo
10:35 am - 12:10 pm
PHL
-
SOF
18h 35m
2 stops
Multiple Airlines Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$742Multiple Airlines
Wed, Sep 9 - Wed, Sep 16
Lufthansa Logo
5:40 pm - 6:05 pm
PHL
-
SOF
17h 25m
1 stop
Lufthansa Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$744Lufthansa
Tue, Sep 8 - Wed, Sep 16
Multiple Airlines Logo
12:02 pm - 2:00 pm
PHL
-
SOF
18h 58m
2 stops
Multiple Airlines Logo
7:00 am - 7:58 pm
SOF
-
PHL
19h 58m
2 stops
$745Multiple Airlines
Sun, Sep 6 - Tue, Sep 15
United Airlines Logo
5:40 pm - 6:10 pm
PHL
-
SOF
17h 30m
1 stop
United Airlines Logo
6:10 am - 4:05 pm
SOF
-
PHL
16h 55m
1 stop
$746United Airlines
Wed, Sep 9 - Wed, Sep 16
United Airlines Logo
10:28 am - 6:40 pm
PHL
-
SOF
25h 12m
2 stops
United Airlines Logo
1:50 pm - 9:43 am
SOF
-
PHL
26h 53m
2 stops
$748United Airlines
Wed, Sep 9 - Wed, Sep 16
United Airlines Logo
10:28 am - 6:40 pm
PHL
-
SOF
25h 12m
2 stops
United Airlines Logo
6:10 am - 5:42 pm
SOF
-
PHL
18h 32m
2 stops
$749United Airlines
Wed, Sep 9 - Wed, Sep 16
Multiple Airlines Logo
10:05 am - 6:05 pm
PHL
-
SOF
25h 00m
2 stops
Multiple Airlines Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$750Multiple Airlines
Sun, Sep 6 - Wed, Sep 16
Lufthansa Logo
5:40 pm - 1:35 pm
PHL
-
SOF
12h 55m
1 stop
Lufthansa Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$751Lufthansa
Sun, Sep 6 - Wed, Sep 16
United Airlines Logo
5:40 pm - 6:10 pm
PHL
-
SOF
17h 30m
1 stop
United Airlines Logo
6:10 am - 5:42 pm
SOF
-
PHL
18h 32m
2 stops
$757United Airlines
Booking Insights

KAYAK's insights & trends for Philadelphia to Sofia flights

Get data-powered insights and trends into flights from Philadelphia 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 Philadelphia 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 Philadelphia to Sofia departing in September.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Philadelphia 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 Philadelphia to Sofia is November, where tickets cost $540 (return) on average. On the other hand, the most expensive months are January and May, where the average cost of round-trip tickets is $7,242 and $1,201 respectively.

Good to know

Low seasonJanuary
Cheapest flight$493
Best time to beat the crowds but there is an average 443% increase in price.
Most popular time to fly and prices are also 41% lower on average.
Flight from Philadelphia to Sofia

When to book flights from Philadelphia to Sofia

Are your dates flexible? Find out the best times to travel from Philadelphia 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 Philadelphia to Sofia

  • What is the cheapest flight from Philadelphia to Sofia?

    In the last 3 days, the lowest price for a flight from Philadelphia to Sofia was $493 for a one-way ticket and $738 for a round-trip.

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

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

  • Which airports will I be using when flying from Philadelphia to Sofia?

    Philadelphia and Sofia are both served by 1 main airport. You will leave Philadelphia from Philadelphia and will be arriving at Sofia.

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

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

  • Which airline alliances offer flights from Philadelphia to Sofia?

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

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

    The two airlines most popular with KAYAK users for flights from Philadelphia to Sofia are United Airlines and Lufthansa. With an average price for the route of $656 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 $780 and an overall rating of 6.8.

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

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

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

Reviews of the top airlines flying from Philadelphia to Sofia

 
See real verified KAYAK customer reviews for airlines flying from Philadelphia 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 Philadelphia 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 9680 reviews
7.3Comfort
7.7Boarding
8.1Crew
7.1Entertainment
6.6Food
Airline reviews

Cree was organized and pleasant. Plane had good seating but as it’s a shuttle toilets hadn’t been thoroughly cleaned (eg. bins too full)

10.0 ExcellentEirene, May 2026
EWR - LHR
Read more United Airlines reviews

Cree was organized and pleasant. Plane had good seating but as it’s a shuttle toilets hadn’t been thoroughly cleaned (eg. bins too full)

I liked that my son and I were reseated next to each other (we had different bookings). I liked that it was a directg flight and mostly on time. I liked that you provided pillows and blankets. Flight attendants were generally courteous. The messaging through wifi did not work well. The food was not good. Seats are very narrow and I felt slightly claustraphobic in the window seat.

Overall a good experience, but no wifi available for free or for purchase and we got wet from condensation or other water source during descent.

Some crew were unfriendly or in some cases just straight up rude.

Booked through Kayak Business, had a seat in middle and towards back due to booking rate, not comfortable.

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

A long delay. Don't travel late in the day.

Super friendly with lots of drink options an entertainment. Friendly crew.

Standard flight with a drinks and a snack- overall very quick flight. The flight attendants were very strict, bordered on rude.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

Flight was delayed by several hours and then cancelled due to weather. But Staff was very helpful getting me on a different flight. United should offer food coupons and tooth brush and paste for stranded passengers

I upgraded to the business class cabin. It was the poorest business class I have ever experienced. No access to any business lounge in Tampa airport. Seats are not comfortable. I had a window seat and had to step/crawl over the next seat. Food was mediocre and service below average for business class. Bathroom location was ridiculous. No place to wait. I cannot believe I paid this kind of money and will never fly Lufthansa Discover again. They really should reimburse me somehow.

Boarding was disorganized. The door to one to the toilets wouldn’t lock. The plane was shockingly cramped, and clearly used for domestic flights due to the menus for items to sell domestic travelers. United should be ashamed of its small seats, tiny unclean toilets, and money grubbing stance toward services, compared to Lufthansa, Emirates, and most international carriers United is awful.

Was never allowed on and not refunded the full amount of the ticket plus charged a $300 processing fee.

Terrible. Lost our luggage for 4 days. Did not advise passengers there was a strike in Barcelona Airport and had zero personnel on hand at airport to advise passengers on where to go to file claims. We had to fend for ourselves. No assistance at all other than an online claims submission process that we had to find out about on our own.

Lufthansa cancelled our flight from Los Angeles to Naples Italy on March 10 for scheduled flight on March 12 Very stressful experience trying to arrange alternatives. Will never fly again with Lufthansa

Everything could have been better. What needed to be wrong with United went wrong

The staff was bit rude when I asked for an extra drink after one beer, asked for one wine glass.

Very good, i got two seats for myself, and was comfortable with the blanket i got

I hated the FRA Airport. Confusing signage, including the path to Immigration and Security It seems that the airport grew haphazardly over the years. I have been through multiple WW Hubs with much better experiences.

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

Information on your arrival and departure airports