PHL - SOF

$455 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 6/15. 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

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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Cheap Flight Deals 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.

Recent round-trip flight deals from Philadelphia to Sofia

KAYAK's recommended round-trip deals from the most popular airlines that fly from Philadelphia to Sofia.
Discover the best prices for you by selecting your travel dates on KAYAK.
Choose your dates
Air Canada Logo
9:45 am - 6:40 pmPHL-SOF
25h 55m2 stops
Air Canada Logo
6:00 am - 2:37 pmSOF-PHL
39h 37m2 stops
$650Air Canada
Find Deal
Sun, Aug 10 - Fri, Aug 22
 Logo
5:35 pm - 1:05 pmPHL-SOF
12h 30m1 stop
 Logo
6:00 am - 2:37 pmSOF-PHL
39h 37m2 stops
Sun, Aug 10 - Fri, Aug 22
British Airways Logo
6:35 pm - 8:40 pmPHL-SOF
19h 05m1 stop
British Airways Logo
9:30 pm - 2:50 pmSOF-PHL
48h 20m2 stops
$699British Airways
Find Deal
Tue, Aug 5 - Wed, Aug 20
 Logo
9:45 am - 6:40 pmPHL-SOF
25h 55m2 stops
 Logo
3:30 pm - 5:35 pmSOF-PHL
33h 05m2 stops
Tue, Oct 7 - Mon, Oct 20
Lufthansa Logo
5:35 pm - 1:15 pmPHL-SOF
12h 40m1 stop
Lufthansa Logo
6:15 am - 4:00 pmSOF-PHL
16h 45m1 stop
$740Lufthansa
Find Deal
Wed, Aug 13 - Wed, Aug 27
 Logo
5:35 pm - 1:20 pmPHL-SOF
12h 45m1 stop
 Logo
3:30 pm - 5:35 pmSOF-PHL
33h 05m2 stops
Tue, Oct 7 - Mon, Oct 20
Lufthansa Logo
5:35 pm - 5:50 pmPHL-SOF
17h 15m1 stop
Lufthansa Logo
6:40 pm - 4:00 pmSOF-PHL
28h 20m1 stop
$759Lufthansa
Find Deal
Tue, Oct 7 - Mon, Oct 20
 Logo
10:35 am - 11:40 amPHL-SOF
18h 05m2 stops
 Logo
6:20 am - 4:00 pmSOF-PHL
16h 40m1 stop
Tue, Sep 16 - Tue, Sep 23
United Airlines Logo
5:35 pm - 5:50 pmPHL-SOF
17h 15m1 stop
United Airlines Logo
6:20 am - 2:40 pmSOF-PHL
15h 20m2 stops
$812United Airlines
Find Deal
Mon, Sep 15 - Tue, Sep 23
United Airlines Logo
5:35 pm - 1:00 pmPHL-SOF
12h 25m1 stop
United Airlines Logo
6:15 am - 4:00 pmSOF-PHL
16h 45m1 stop
$826United Airlines
Find Deal
Mon, Sep 15 - Wed, Sep 24

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 February, where tickets cost $560 (return) on average. On the other hand, the most expensive months are June and May, where the average cost of round-trip tickets is $1,371 and $1,255 respectively.

Good to know

Low season

February

High season

June

Cheapest flight

$455
Best time to beat the crowds with an average 36% drop in price.
Most popular time to fly with an average 57% 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 $455 for a one-way ticket and $650 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, and oneworld are the airline alliances operating flights between Philadelphia and Sofia, with Star Alliance being the most commonly used for this route.

  • 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 $826 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 $1,050 and an overall rating of 6.7.

  • 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.

See more FAQs

Top 3 airlines serving 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 8665 reviews
8.1Crew
7.1Entertainment
7.3Comfort
6.6Food
7.7Boarding
Airline reviews

Smooth flight. Boarding was chaotic. Could not hear the gate agent over the intercom. People were lined up in the wrong lines. Groups one and two were told to board through line one and group 3 through line 2. All very confusing. Once in the air, the flight was smooth. There was no entertainment option on this aircraft, even though it was a larger aircraft.

10.0 ExcellentDr. Joseph, Apr 2025IAH - ORD
Read more United Airlines reviews

Smooth flight. Boarding was chaotic. Could not hear the gate agent over the intercom. People were lined up in the wrong lines. Groups one and two were told to board through line one and group 3 through line 2. All very confusing. Once in the air, the flight was smooth. There was no entertainment option on this aircraft, even though it was a larger aircraft.

The plane pushed back from the gate on time. However, it stopped on the ramp, and we waited for over 20 minutes before the aircraft pulled back to the gate. Apparently, something of importance had to be removed from the aircraft by the gate agent. I found this to be odd. The delay was not significant, but I felt that whatever was on the aircraft that had to be taken off, should’ve been done before we pushed back from the gate.

I didn’t get on plane. Passport being processed by consulate with visa application. Tried to cancel through underpricer after purchasing cacelling for any reason. No dice, they are thieves.

Electric plugs didn't work. Entertainment system wasn't working

The design of the light switch on the arm rest is ridiculous.

Smooth boarding process. Early departure, smooth flight, early arrival. The entertainment package has very good recent movie options. The flight crew were friendly and professional.

leg space better than expected. two washrooms for one plane isn't enough.

My suitcase was completed destroyed. The top part is broken and unusable now.

When I booked it on Kayak it aaid that I wasn't allowed hamd luggage. I called United Airlines and it took them 6 minutes to figure out if I was allowed free hand luggage. Surely something that simple they should be able to tell me instantly.

The gate attendant let me walk right by her with a bag too big for the overhead compartment

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.

My flight was late from US to Frankfurt so I missed my connecting flight flight and I had to wait for long to catch the next flight which was very tiring. Otherwise everyone was very nice.

It would have been nice if my luggage had made it onto my connecting flight as well. Now I have to wait for my luggage to be delivered and that might take a while, which certainly put a damper on the entire experience.

Crew was not happy. Very uncomfortable seats. When person leans back in front of you the screen is too close to me. Food was awful.

They lost my luggage and despite all follow ups through emails and phone calls they don’t give me an update

Everything went really well. Snacks could be better and there was no tea/coffee service after dinner. Crew was helpful and friendly.

Business class seats were very dated on my plane. Very little storage, charging ports were not easily accessible, tv screen kept flopping away. Vegetarian food was disappointing: hardly any protein and severely under-seasoned. Crew was lovely.

The food was ok, but not great. They delayed boarding in Portland and did not enforce group boarding. But the crew was excellent, went above and beyond.

The food was pathetic. There wasn't much leg room and recline space for such a long flight. No tea/ coffee for a 2-3 hour connecting flight without purchasing! Really!?

Service was very good. Because I use a cane, I was allowed to use Priority Boarding. Biggest problem was extremely limited leg room in Economy class seats. For airplane food, it was alright.

Was late but that airport/storm fault. Flight was full but comfortable. Food quite nice. Unfortunate that I had a rather miserable attendant, others were much friendlier

Experience was good. Could have been better if we didn’t have to board an hour before the flight to ghana and miss relaxing time in the lounge. That process was very stressful

Boarding crew is unfriendly as i was asked to handover carryon luggage too upto final destination Bangalore I was not prepared for that and i had to travel without my diabetic and hypertension medicines

I was charged fees for check in bags at the airport by British Airways. It was supposed to be no charge but Kayak messed up my booking apparently and I had to pay for check in bags. I paid $175.

They took my carry on and checked it in. Staff in general at Heathrow are not friendly or helpful

The crew were professional and friendly. It was the most uncomfortable international flight I've ever flown. Crammed in passengers. No overhead space to put my bag. No leg room and unable to recline seat due to seats too close together so it upset passenger behind me! Upgrade price to get 2 inches of more space unreasonable.

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

Information on your arrival and departure airports

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