$400 Cheap Flights from Philadelphia (PHL) to Sofia (SOF)

View $400 flight on Sun, Nov 23, 2025Opens in a new window

Popular airlines from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)

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Cheap Flights from Philadelphia to Sofia (PHL-SOF)

Prices were available within the past 7 days and start at $400 for one-way flights and $478 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Wed, Nov 19 - Tue, Nov 25
PHL
Philadelphia
SOF
Sofia
$478 Roundtrip, found 2 days ago
$478
Roundtrip
found 2 days ago
Select Air Canada flight, departing Wed, Nov 19 from Philadelphia to Sofia, returning Tue, Nov 25, priced at $478 found 2 days ago
Air Canada
Sun, Nov 16 - Wed, Nov 26
PHL
Philadelphia
SOF
Sofia
$478 Roundtrip, found 4 days ago
$478
Roundtrip
found 4 days ago
Select Air Canada flight, departing Sun, Nov 16 from Philadelphia to Sofia, returning Wed, Nov 26, priced at $478 found 4 days ago
Air Canada
Mon, Jan 26 - Tue, Feb 3
PHL
Philadelphia
SOF
Sofia
$479 Roundtrip, found 2 days ago
$479
Roundtrip
found 2 days ago
Select Air Canada flight, departing Mon, Jan 26 from Philadelphia to Sofia, returning Tue, Feb 3, priced at $479 found 2 days ago
United
Tue, Nov 18 - Tue, Nov 25
PHL
Philadelphia
SOF
Sofia
$482 Roundtrip, found 6 hours ago
$482
Roundtrip
found 6 hours ago
Select United flight, departing Tue, Nov 18 from Philadelphia to Sofia, returning Tue, Nov 25, priced at $482 found 6 hours ago
United
Wed, Jan 7 - Thu, Feb 12
PHL
Philadelphia
SOF
Sofia
$482 Roundtrip, found 1 day ago
$482
Roundtrip
found 1 day ago
Select United flight, departing Wed, Jan 7 from Philadelphia to Sofia, returning Thu, Feb 12, priced at $482 found 1 day ago
United
Mon, Nov 24 - Tue, Mar 31
PHL
Philadelphia
SOF
Sofia
$483 Roundtrip, found 21 hours ago
$483
Roundtrip
found 21 hours ago
Select United flight, departing Mon, Nov 24 from Philadelphia to Sofia, returning Tue, Mar 31, priced at $483 found 21 hours ago
British Airways
Tue, Mar 17 - Wed, Apr 8
PHL
Philadelphia
SOF
Sofia
$483 Roundtrip, found 2 days ago
$483
Roundtrip
found 2 days ago
Select British Airways flight, departing Tue, Mar 17 from Philadelphia to Sofia, returning Wed, Apr 8, priced at $483 found 2 days ago
Air Canada
Wed, Nov 19 - Tue, Nov 25
PHL
Philadelphia
SOF
Sofia
$484 Roundtrip, found 6 hours ago
$484
Roundtrip
found 6 hours ago
Select Air Canada flight, departing Wed, Nov 19 from Philadelphia to Sofia, returning Tue, Nov 25, priced at $484 found 6 hours ago
KLM
Wed, Jan 7 - Thu, Jan 15
PHL
Philadelphia
SOF
Sofia
$551 Roundtrip, found 2 days ago
$551
Roundtrip
found 2 days ago
Select KLM flight, departing Wed, Jan 7 from Philadelphia to Sofia, returning Thu, Jan 15, priced at $551 found 2 days ago
Austrian Airlines
Wed, Dec 31 - Sat, Feb 28
PHL
Philadelphia
SOF
Sofia
$599 Roundtrip, found 1 day ago
$599
Roundtrip
found 1 day ago
Select Austrian Airlines flight, departing Wed, Dec 31 from Philadelphia to Sofia, returning Sat, Feb 28, priced at $599 found 1 day ago

Alternative airports near Sofia

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Sofia Airport SOF. Cheapest and Closest option available. Average driving time to city center is 11 minutes. Flights from $960
SOF
Sofia Airport
CheapestClosest
Average driving time to city center11 min
Flights from $960

Frequently asked questions

How much does a flight from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF) cost?
Get a cheap one-way flight from $400 or cheap return flight from $478 from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)?
Planning your trip for November is a great way to save, as it's the cheapest month for flights between PHL and SOF. You'll typically find the lowest fares during the off-season.
What is the cheapest airline that flies from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)?
Expedia's filter tool lets you easily compare travel time, airlines and fares all in one place. Tailor the search to your trip, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest PHL to SOF flight.
How many flights per day from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)?
Direct flights from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF) aren't available daily, so you'll need to take a flight with a layover. Explore your options with our filter tool. Enter your dates and choose either "1 Stop" or "2+ Stops."
What day of the week has the most flights from PHL to SOF?
Usually you'll find the widest variety of flight choices on a Friday. Tuesdays tend to be the quietest.* However, this can vary based on the season, carrier and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)?
To touch down at Sofia Airport (SOF) without delays, pick a flight that leaves from Philadelphia Intl. Airport (PHL) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF) last-minute?
Last-minute fares from PHL to SOF are generally more expensive. To secure the best prices, start searching for flights ahead of time. That said, if you're flexible with your travel dates, it's possible to score a cheap ticket just before your departure.
Is it cheaper to book a PHL to SOF flight and hotel package?
You'll typically save money by securing a PHL to SOF flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's easy to manage it all in one convenient place. Once you've selected your preferred accommodations and flights, consider other add-ons like activities, car rentals and tours.
Can I cancel or change the date of my flight from Philadelphia Intl. Airport (PHL) to Sofia Airport (SOF)?
If you booked your PHL to SOF flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the fare type you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal for more details.

Travel information

Origin airport
Philadelphia Intl.
Destination airport
Sofia
Airlines serving
Air Canada, Air France, Austrian Airlines, British Airways, KLM, Lufthansa, Swiss International Air Lines, Turkish Airlines, United
Roundtrip price
$477
Distance
4802 mi

Book with confidence

Philadelphia to Sofia Flights

The cheapest times to fly from Philadelphia to Sofia

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Philadelphia to Sofia are during the month of November. You can find some of the cheapest flights from Philadelphia to Sofia with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Philadelphia to Sofia

Sunday is one of the best days to book for cheap flights from Philadelphia to Sofia: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Philadelphia to Sofia

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Philadelphia to Sofia in 2025. You can also book with separate airlines for your outbound and return journeys, from $400 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Philadelphia to Sofia flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Philadelphia to Sofia airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Philadelphia to Sofia Flights

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