PHL - SOF

$399 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 10/19. 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

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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Flights 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

Mon, Sep 22 - Fri, Jan 16
 Logo
3:25 pm - 10:50 pmPHL-SOF
24h 25m2 stops
 Logo
6:15 am - 3:49 pmSOF-PHL
40h 34m2 stops
Tue, Sep 30 - Wed, Apr 1
British Airways Logo
7:50 pm - 8:40 pmPHL-SOF
17h 50m1 stop
British Airways Logo
9:30 pm - 1:05 pmSOF-PHL
22h 35m1 stop
$673British Airways
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Mon, Sep 22 - Fri, Jan 16
 Logo
5:35 pm - 5:50 pmPHL-SOF
17h 15m1 stop
 Logo
6:15 am - 3:49 pmSOF-PHL
40h 34m2 stops
Wed, Oct 1 - Wed, Apr 1
United Airlines Logo
5:35 pm - 1:15 pmPHL-SOF
12h 40m1 stop
United Airlines Logo
6:15 am - 2:37 pmSOF-PHL
15h 22m2 stops
$685United Airlines
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Tue, Sep 30 - Thu, Mar 26
United Airlines Logo
3:25 pm - 1:20 pmPHL-SOF
14h 55m2 stops
United Airlines Logo
6:00 am - 5:00 pmSOF-PHL
17h 00m1 stop
$686United Airlines
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Sat, Oct 4 - Thu, Apr 2
Lufthansa Logo
4:50 pm - 12:00 pmPHL-SOF
36h 10m2 stops
Lufthansa Logo
6:15 am - 4:00 pmSOF-PHL
16h 45m1 stop
$688Lufthansa
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Sat, Sep 27 - Wed, Mar 25
Air Canada Logo
4:50 pm - 12:00 pmPHL-SOF
36h 10m2 stops
Air Canada Logo
1:55 pm - 2:47 pmSOF-PHL
30h 52m2 stops
$700Air Canada
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Sun, Sep 28 - Fri, Mar 27
Lufthansa Logo
5:35 pm - 5:50 pmPHL-SOF
17h 15m1 stop
Lufthansa Logo
6:05 am - 10:56 pmSOF-PHL
22h 51m2 stops
$703Lufthansa
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Sun, Sep 28 - Sat, Mar 28
Air Canada Logo
7:30 am - 12:00 pmPHL-SOF
21h 30m2 stops
Air Canada Logo
6:15 am - 10:29 pmSOF-PHL
46h 14m2 stops
$744Air Canada
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Sat, Sep 27 - Sat, Mar 28
American Airlines Logo
6:45 pm - 8:20 pmPHL-SOF
18h 35m2 stops
American Airlines Logo
12:05 pm - 9:00 amSOF-PHL
26h 55m2 stops
$790American Airlines
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 February, where tickets cost $560 (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 $1,114 respectively.

Good to know

Low seasonFebruary
Cheapest flight$399
Best time to beat the crowds with an average 31% drop in price.
Most popular time to fly with an average 4% 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 $399 for a one-way ticket and $667 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?

    oneworld, Star Alliance, and SkyTeam 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 $795 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 $847 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 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 8896 reviews
6.6Food
7.1Entertainment
7.7Boarding
8.1Crew
7.3Comfort
Airline reviews

Was on time until within 1 hour of flight-how does that happen? Staff very friendly.

8.0 ExcellentHal, Jul 2025IAD - MSY
Read more United Airlines reviews

Was on time until within 1 hour of flight-how does that happen? Staff very friendly.

the delay for 3 hours was understandable due to weather conditions but the flight should’ve provided some on flight compensations or at least provide more food.

Weather delay in Chicago?. No sense of urgency to make connection in Chicago for our connecting flight that wasn't delayed. Connection was missed.

Ridiculous boarding. Enter the gate, walk down a staircase with bags, exit a building, get on a crowded bus, dropped off a few meters away from the aircraft, walk with bags to another set of stairs to board the aircraft. And all that during a pouring down rain, and with children. Ridiculous!!!

Our flight was understandably diverted to a small regional airport in Laramie, Wyoming due to weather conditions, which I fully recognize and appreciate. However, the low rating stems from the experience that followed: passengers remained on board for over an hour without the option to deplane and stretch, despite the aircraft being stationary. Although the pilot opened the cabin door, only he was permitted to exit. Meanwhile, passengers grew increasingly uncomfortable as warm summer air entered the cabin through the open door, and being in the second row meant we were impacted immediately. While the flight attendants made efforts to keep everyone at ease, I believe allowing passengers to deplane briefly, given the extended delay, would have significantly improved the overall experience.

I never flew. Flight was canceled. DIA worst airport in the country. Avoid at all costs.

I learned that seating towards the end of plane that a line forms for the restroom and people use your chair as a hand railing, bumping your seat consistently. I was seated in the aisle. I think that next time if I am towards the back row I would want to sit in the middle or window seat.

The best airline I have ever travel , really good customer service, attention and service !!

United could have one single once of customer service. No human United employee would help me with the invalid mileage plus number, they said I had to speak with the computer.

United sent me a mileage plus number last year but that number is invalid so I can’t use it to check into flights or collect mileage. There is human to speak about the problem, only computers who keep asking me if I am using the correct email. It’s so frustrating and I cannot resolve it.

Hate their old flights, boatding, food and services. Very poor quality

Insulting. Lufthansa flight from Munich to EWR had us getting our luggage when we were told in Florence that it would follow us to Indianapolis. It did not. Then very slow security in EWR caused me and three other passengers from Lufthansa flight from Munich to miss the boarding closure. Behind me were two elderly grandparents and their ten year old grandson. We were all refused entry on a plane to Indy that was still at the gate. The doors had not even closed inside the terminal yet. No apologies or compensation offered. Not even a meal voucher let alone a free hotel stay for our inconvenience. I m not sure what the other three passengers behind me did ( they were elderly with a grandson, recall), but I stated 12 hours overnight in a chilly EWR airport until next flight to Indy at 850 next morning.

The food could be better, more snacks. And have some plugs to chargue the phone.

The pasta in the evening meal was tasteless. Otherwise, the flight was okay.

Everything was really great just The aircraft was too old and sounded it will break during takeoff

Seating was average for a first class seat. It very modern. I expected better.

Flight was a little late. The crew was courteous, food ok

Bad! Disaster!! The LH419 was cancelled after 4 hrs on board with no AC and no toilets

Poor food on flight between Toronto and Stockholm Airport Toronto too crowded

Extremely pleased with the crew. Best flight attendants ever! Very friendly, genuinely caring and attentive.

My experience with British Airways is excellent, thanks for all 🫶🏻✈️

Old tired plane, Uncomfortable business class seat. Breakfast dreadful and meagre. At least flight was on time!

Safe arrival. Improvement on Time efficiency Effective Communication will be great.

The crew is very friendly and helpful. The food is good for airplane food. The flight is long and hard to sleep. The leg space is great. The plane arrived in plenty of time.

A good flight back to Tampa and thankfully although we had a 90 minute delay because of thunder storms from Charlotte to bottom iof Florida, it was a prudent to avoid these for a comfortable flight as opposed to being tossed around with turbulence.

They removed our booking without telling us. Cost us thousands to book last minute

Enjoyable flight, helpful crew everything was organized to accommodate passengers.

Captain sick. Unable to get replacement so delayed me 30 hours, many others delayed 54 hours. TOTALLY DESTROYED ALL MY PLANS, including lost my rental car which would now cost over 5 times what I paid so stuck with buses n trains... lost hotel reservations.... HORRIBLE!!!

The international flight from PHL to Lisbon was one of the worst I’ve experienced, ever. What was really disappointing was the entire experience of comfort and service in the coach cabin after takeoff. The food was inedible and the wine served with dinner was such low quality - it tasted of petrol. I couldn’t eat more than a bite or two of the chicken entree, being worried it would make me ill. The service took so long to reach the entire coach cabin, I ended up having the lights turned off on me as though I had to rush though dinner (though as I mentioned, it wasn’t as if I ate much - only the salad). Most of the attendants seemed generally annoyed and were not friendly or polite. While there was some turbulence, it wasn’t too uncomfortable and I know that is just a chance. The temperature of the cabin was so warm, even a friend a row or two up and on the other side of the plane felt like this. To top it all off, the seat was so uncomfortable and flattened/overused, I had back pains for DAYS afterward.

They’ve lost my bag and I have no way of really getting in touch with anyone and have received no updates.

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

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