PHL - SOF

$479 Find Cheap Flights from Philadelphia 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 Philadelphia to Sofia departing on 11/19. 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
$479
Overall average: $582
Lufthansa
Wed 11/19Thu 11/27
PHL - SOF • 2 stops
Cheapest one-way
Multiple Airlines
Sun 11/2
PHL - SOF • multi-stop
Top airlines
Lufthansa
Cheapest • from $479 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
October
Cheapest • 33% price drop
August
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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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, Nov 19 - Thu, Nov 27
Lufthansa Logo
3:30 pm - 1:15 pmPHL-SOF
14h 45m2 stops
Lufthansa Logo
6:00 am - 4:05 pmSOF-PHL
17h 05m1 stop
$479Lufthansa
Find Deal
Tue, Mar 31 - Tue, Apr 7
Multiple Airlines Logo
3:30 pm - 6:40 pmPHL-SOF
20h 10m2 stops
Multiple Airlines Logo
6:10 am - 4:00 pmSOF-PHL
16h 50m1 stop
$480Multiple Airlines
Find Deal
Mon, Nov 17 - Thu, Nov 27
United Airlines Logo
3:00 pm - 10:45 pmPHL-SOF
24h 45m2 stops
United Airlines Logo
6:00 am - 2:47 pmSOF-PHL
15h 47m2 stops
$483United Airlines
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Wed, Nov 19 - Mon, Dec 1
Air Canada Logo
9:20 am - 6:20 pmPHL-SOF
26h 00m2 stops
Air Canada Logo
1:45 pm - 10:46 pmSOF-PHL
40h 01m2 stops
$533Air Canada
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Wed, Mar 25 - Sun, Mar 29
United Airlines Logo
4:56 pm - 6:20 pmPHL-SOF
19h 24m2 stops
United Airlines Logo
6:10 am - 4:00 pmSOF-PHL
16h 50m1 stop
$535United Airlines
Find Deal
Sun, Nov 16 - Wed, Nov 26
British Airways Logo
6:35 pm - 4:20 pmPHL-SOF
14h 45m1 stop
British Airways Logo
9:00 pm - 4:15 pmSOF-PHL
26h 15m1 stop
$544British Airways
Find Deal
Tue, Nov 18 - Mon, Dec 1
Air Canada Logo
9:20 am - 1:45 pmPHL-SOF
21h 25m2 stops
Air Canada Logo
2:20 pm - 10:46 pmSOF-PHL
39h 26m2 stops
$554Air Canada
Find Deal
Sun, Nov 16 - Mon, Dec 1
British Airways Logo
6:35 pm - 4:20 pmPHL-SOF
14h 45m1 stop
British Airways Logo
5:25 pm - 4:15 pmSOF-PHL
29h 50m1 stop
$574British Airways
Find Deal
Tue, Nov 18 - Thu, Nov 27
SWISS Logo
5:40 pm - 3:15 pmPHL-SOF
38h 35m2 stops
SWISS Logo
4:00 pm - 9:21 pmSOF-PHL
36h 21m3 stops
$776SWISS
Find Deal
Tue, Nov 18 - Sun, Nov 30
SWISS Logo
5:40 pm - 3:15 pmPHL-SOF
38h 35m2 stops
SWISS Logo
11:00 am - 4:05 pmSOF-PHL
60h 05m2 stops
$781SWISS
Find Deal
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.

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

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

If you are looking for a flight deal from Philadelphia to Sofia, look for departures on Tuesdays and avoid leaving on a Saturday, as it's usually the priciest day. When flying back from Sofia, Wednesday is the cheapest day to fly and Thursday is the most expensive.

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 October, where tickets cost $518 (return) on average. On the other hand, the most expensive months are May and June, where the average cost of round-trip tickets is $1,255 and $1,093 respectively.

Good to know

Low seasonFebruary
Cheapest flight$479
Best time to beat the crowds with an average 28% drop in price.
Most popular time to fly with an average 7% increase in price.
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 $479 for a round-trip ticket.

  • 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 $794 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 $832 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 8997 reviews
6.6Food
7.7Boarding
8.1Crew
7.1Entertainment
7.3Comfort
Airline reviews

Short flight but an "eager to help" crew made the journey more enjoyable!

10.0 ExcellentAlan, Oct 2025IAD - PVD
Read more United Airlines reviews

Short flight but an "eager to help" crew made the journey more enjoyable!

Flight was delayed only slightly before takeoff due to traffic control. However, the flight arrived early to ORD. Good flight. United has been very reliable for me.

The person I bought the ticket for didn’t make the flight.

Lately I like the planes have been exceptionally filthy. There’s lines of dust and dirt all across the ceiling in the vents, and the cracks in between the seats are literally full of food. It’s definitely not the quality of service that I was used to with United. I’m also very disappointed with the Wi-Fi! All I wanna do is knock out a few work jobs while I’m trapped in my seat And it spools so bad. They did provide me with a refund, but the process of getting that refund is so complicated. It’s unfortunate.

Another delayed flight. When the delays exceed the duration of the flight, it’s a problem.

Excellent flight. Smooth, efficient boarding. Quick flight. Arrived early at STL.

After boarding the plane in Chicago, the passengers were told that there was a technical problem with the plane. Passengers remained on the plane as they tried to fix the problem. After what was probably an hour passengers were told that there was a need to change planes as the problem was not solved. Passengers disembarked and boarded another plane. After taxing to the runway and waiting for takeoff, passengers were told that owing to the thunderstorm the flight was unable to take off but would try and reroute. After some time passengers were told there wasn't enough fuel for the new route and the plane had to return to the gate for additional fuel. after another log delay the flight got underway. On the plane there was food, drinks, ice or entertainment. We were a glass of water, which appeared rationed. Flight arrived about 5 hours late. The pilot was fantastic and communicated with the passengers throughout the ordeal.

Same as last comment. Food sucks. Quality. Not surprising most people have no clue about nourishment Clearly

Not the fault of United—weather, reroute around weather, time sitting on tarmac, arrived couple hours late, too late for train into city necessitating a much pricier cab but weather…can’t be helped.

Friendly and professional flight crew. Aside from departure delay after boarding, easy flight and smooth landing.

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 Philadelphia to Sofia

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