PHL - SOF

$341 Find Cheap Flights from Philadelphia 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 Philadelphia to Sofia departing on 8/18. 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
$719
Typical prices: $1,143-$574
United Airlines
Tue 8/4Thu 8/20
PHL - SOF • 2 stops
Cheapest one-way
$341
Multiple Airlines
Tue 8/18
PHL - SOF • 3 stops
Top airlines
Cheapest • from $718 (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 • 61% 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

Tue, Aug 4 - Thu, Aug 20
United Airlines Logo
7:45 pm - 6:40 pm
PHL
-
SOF
15h 55m
2 stops
United Airlines Logo
6:10 am - 12:59 am
SOF
-
PHL
25h 49m
2 stops
$719United Airlines
Sun, Sep 6 - Fri, Sep 18
Multiple Airlines Logo
10:05 am - 6:40 pm
PHL
-
SOF
25h 35m
2 stops
Multiple Airlines Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$736Multiple Airlines
Mon, Sep 7 - Fri, Sep 18
United Airlines Logo
3:05 pm - 12:10 pm
PHL
-
SOF
14h 05m
2 stops
United Airlines Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$738United Airlines
Sun, Sep 6 - Fri, Sep 18
Air Canada Logo
10:05 am - 6:40 pm
PHL
-
SOF
25h 35m
2 stops
Air Canada Logo
6:20 am - 9:32 pm
SOF
-
PHL
22h 12m
2 stops
$740Air Canada
Tue, Sep 1 - Tue, Sep 15
Lufthansa Logo
5:40 pm - 1:05 pm
PHL
-
SOF
12h 25m
1 stop
Lufthansa Logo
6:10 am - 4:05 pm
SOF
-
PHL
16h 55m
1 stop
$741Lufthansa
Sat, Sep 5 - Thu, Sep 17
Air Canada Logo
4:20 pm - 6:40 pm
PHL
-
SOF
43h 20m
2 stops
Air Canada Logo
6:30 am - 2:47 pm
SOF
-
PHL
39h 17m
2 stops
$744Air Canada
Sun, Sep 6 - Fri, Sep 18
Lufthansa Logo
5:40 pm - 6:10 pm
PHL
-
SOF
17h 30m
1 stop
Lufthansa Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$745Lufthansa
Sat, Sep 5 - Fri, Sep 18
Air Canada Logo
4:20 pm - 6:40 pm
PHL
-
SOF
43h 20m
2 stops
Air Canada Logo
6:20 am - 10:46 pm
SOF
-
PHL
23h 26m
2 stops
$749Air Canada
Mon, Jul 27 - Wed, Aug 12
Multiple Airlines Logo
7:00 am - 12:10 pm
PHL
-
SOF
22h 10m
2 stops
Multiple Airlines Logo
6:55 pm - 4:05 pm
SOF
-
PHL
28h 10m
2 stops
$750Multiple Airlines
Sat, Sep 5 - Fri, Sep 18
Lufthansa Logo
3:25 pm - 6:10 pm
PHL
-
SOF
43h 45m
2 stops
Lufthansa Logo
6:20 am - 4:05 pm
SOF
-
PHL
16h 45m
1 stop
$754Lufthansa
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 August.

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 April, where tickets cost $514 (return) on average. On the other hand, the most expensive months are January and December, where the average cost of round-trip tickets is $7,242 and $1,187 respectively.

Good to know

Low seasonJanuary
Cheapest flight$341
Best time to beat the crowds but there is an average 443% increase in price.
Most popular time to fly and prices are also 60% 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 5 days, the lowest price for a flight from Philadelphia to Sofia was $341 for a one-way ticket and $718 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 $614 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 $798 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 9805 reviews
7.7Boarding
7.1Entertainment
7.3Comfort
6.6Food
8.1Crew
Airline reviews

Smooth travel. Immediate update prior flight delay so I can arrange myself properly without too rush.

10.0 ExcellentNakin, Jun 2026
ORD - HND
Read more United Airlines reviews

Smooth travel. Immediate update prior flight delay so I can arrange myself properly without too rush.

Everything was the best it could be. Crew found me with pre- ordered food. Excellent experience!

Improve the food offerings and cabin seating. My wife would prefer to fly another airline, even with a connection for a more comfortable trip. A 737-8 should not be scheduled for a 6 hour segment, which turned into 7.5 hours due to the origin ground delay.

Packed flight, which makes it tough on crew and boarding staff (and the customers of course). But this was great boarding, clear instructions, etc. Traveling on the weekends are always fraught with danger as you have families and less frequent flyers thus more confusion. But this flight went as planned.

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

Read the fine print. This was my flight home. I booked my flight for the quickest way home. Had a carry-on and a personal item. Same as my outbound flight. Apparently I needed to pre-pay extra for my carry-on. When I checked in, I was told that I had to check it. I said I’ll pay for it, and was told that this wasn’t an option anymore. They said I still had to pay $50 to check my carry-on. I told them I’ll pay whatever to just carry it in as intended. I was not allowed, so eventually I paid $50 to check my carry-on under a plane that was half full, with overhead compartments that were even less full. My white carry-on suitcase was practically destroyed getting from Idaho falls to Denver to Orange County. The low price air fair was a bait and switch. Got me to the gate, made me pay extra, then didn’t even allow me to pay for a carry on. Not to mention that I paid the $8 for WiFi that didn’t work. All to get my suitcase destroyed. I don’t think I’m going to even keep my Untied mileage plus membership and card. Apparently, membership does not have its privileges for this one.

The flight was delayed, they didn’t even have water for the toilets or for drinks

Even through the flight was delayed due to storms near IAH The flight was great! The crew was so hospitable and professional

I flew from Santa Fe to Denver to catch a flight to London and the transfer of my luggage on arrival at Denver to the London flight worked perfectly. The crew on the ground and on board for the London flight were so friendly and efficient.

Boarded early; and arrived home 40 mins early. After a long flight, it’s nice to be back home early. These flights have no amenities; no snacks. So need to bring your own

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.

Food choices limited & not enticing Seats quite uncomfortable & difficult to control

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

Information on your arrival and departure airports