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Sofia

$616+ Cheap flights from Philadelphia (PHL) to Sofia (SOF)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/31. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — SOF
Apr 18 — Apr 251
Sat 4/18
Sat 4/25
1 adult, Economy
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Cheap flight deals from Philadelphia to Sofia

Cheapest flights from Philadelphia to Sofia
Explore the most affordable flight options available from Philadelphia to Sofia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 19, 2026.

This United Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/317:45 pm
PHL
-
SOF
2 stops20h 15m
United Airlines
Tue 4/72:10 pm
SOF
-
PHL
2 stops26h 48m
United Airlines
Deal found 3/15$616
This FlightHub deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/315:40 pm
PHL
-
SOF
1 stop12h 25m
Lufthansa
Tue 4/76:10 am
SOF
-
PHL
2 stops16h 55m
Lufthansa
Deal found 3/15$630
This United Airlines deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/911:30 am
PHL
-
SOF
2 stops18h 55m
United Airlines
Wed 9/166:20 am
SOF
-
PHL
2 stops15h 27m
United Airlines
Deal found 3/15$652
This Air Canada deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/183:30 pm
PHL
-
SOF
2 stops19h 50m
Air Canada
Sun 11/226:10 am
SOF
-
PHL
2 stops15h 37m
Air Canada
Deal found 3/15$658
This Air Canada deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/410:05 am
PHL
-
SOF
2 stops17h 55m
Multiple Airlines
Thu 8/206:30 am
SOF
-
PHL
2 stops15h 19m
Multiple Airlines
Deal found 3/17$670
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/41:26 pm
PHL
-
SOF
2 stops22h 14m
United Airlines
Tue 5/266:10 am
SOF
-
PHL
2 stops22h 23m
United Airlines
Deal found 3/17$690

Find flight deals from Philadelphia to Sofia

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) to Sofia (SOF). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 19, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$616
(United Airlines)

One-way from

$532
(Kiwi.com)

Popular in

January

Cheapest in

November

Average price

$546
Provider with most accurate pricing for Philadelphia-Sofia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Philadelphia-Sofia flights.
Search Deals
From Philadelphia to Sofia
Search Deals
One-way flight from Philadelphia to Sofia
Search Deals
Highest demand for flights based on searches. 56% potential increase in price ($1,699 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 69% potential price decrease ($539 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Philadelphia to Sofia that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 19, 2026.
Use the filters below to find and compare flights from Philadelphia to Sofia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Tue 3/31

7:45 pm-11:00 pm

2 stops20h 15m

Sofia

Tue 4/7

2:10 pm-9:58 am

2 stops26h 48m

$616

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Mon 5/4

1:26 pm-6:40 pm

2 stops22h 14m

Sofia

Tue 5/12

6:10 am-2:20 pm

2 stops39h 10m

$666

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Wed 9/9

9:52 am-1:25 pm

2 stops20h 33m

Sofia

Wed 9/16

6:10 am-12:50 am

2 stops25h 40m

$710

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Tue 7/7

9:21 am-11:00 pm

2 stops30h 39m

Sofia

Wed 7/22

6:20 am-9:34 pm

2 stops22h 14m

$787
Quickest round-trip

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Fri 7/24

6:10 am-1:15 pm

2 stops24h 05m

Sofia

Sat 8/29

6:20 am-9:21 pm

2 stops22h 01m

$860

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Sun 7/5

10:05 am-1:35 pm

2 stops20h 30m

Sofia

Tue 7/21

2:10 pm-9:39 am

2 stops26h 29m

$906

PhiladelphiaSofia

PHL - SOF

PHLSOF

Philadelphia

Tue 6/9

5:30 pm-8:30 pm

2 stops20h 00m

Sofia

Wed 6/24

9:25 pm-4:40 pm

1 stop26h 15m

$945

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/15

Sorted by cheapest first

Compare providers for flights from Philadelphia to Sofia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Philadelphia to Sofia in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
Justfly.comPrice Accuracy3 starsTrust Score*3 stars
BudgetAirPrice Accuracy1 starTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
Trip.comPrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Philadelphia-Sofia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Philadelphia-Sofia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Philadelphia-Sofia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Philadelphia-Sofia flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Philadelphia-Sofia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Philadelphia to Sofia

Have a flexible travel schedule? Discover the best time to fly to Sofia from Philadelphia with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

What is the cheapest month to book a flight from Philadelphia to Sofia?

Currently, October is the cheapest month in which you can book a flight from Philadelphia to Sofia (average of $223). Flying from Philadelphia to Sofia in May is currently the most expensive (average of $531). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Reviews of airlines servicing Sofia

Get insights into the airlines that provide service to Sofia. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Sofia. Reviews last updated March 19, 2026.
Read reviews from past customers who have flown United Airlines and Lufthansa from Philadelphia to Sofia. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,439 reviews

Boarding

7.7

Overall

7.4

Food

6.6

Crew

8.1

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
United Airlines
7.4
Good
9,439 reviews
United Airlines
7.4
Good
9,439 reviews

Boarding

7.7

Overall

7.4

Food

6.6

Crew

8.1

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Lufthansa
6.8
Okay
7,856 reviews
United Airlines
7.4
Good
9,439 reviews

Boarding

7.7

Overall

7.4

Food

6.6

Crew

8.1

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family

Related info for your journey

Find useful and relevant information for your journey from Philadelphia to Sofia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Philadelphia to Sofia?

    A quick flight from Philadelphia to Sofia can take about 12h 25m. United Airlines provides one of the quickest options available for as low as $630. Philadelphia and Sofia are separated by a distance of 4800 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from Philadelphia to Sofia round-trip?

    According to our current data, Lufthansa ($511), and United Airlines ($540) offers the cheapest pricing from Philadelphia to Sofia. These flights start at 61% lower than the current average price 3 months from now.

  • Can I find deals for flights from Philadelphia to Sofia that include hotel bookings?

    Yes. In addition to deals on Philadelphia to Sofia flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Philadelphia to Sofia?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Philadelphia to Sofia.

  • Can I find deals for business class flights from Philadelphia to Sofia?

    Yes. Cheapflights offers flight deals from Philadelphia to Sofia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Philadelphia to Sofia?

    Currently, October is the cheapest month in which you can book a flight from Philadelphia to Sofia (average of $223). Flying from Philadelphia to Sofia in May is currently the most expensive (average of $531). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Philadelphia to Sofia

See prices for flight routes from nearby airports that may be better suited for you.
John F Kennedy Intl to Sofia flights
Newark to Sofia flights
Dulles Intl to Sofia flights
Pittsburgh to Sofia flights

Top 2 airlines flying from Philadelphia to Sofia

Discover the top 2 airlines that operate flights from Philadelphia to Sofia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 19, 2026.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest$511Average$759FlexibilityNo cancel feeOn-time76%
United AirlinesCheapest$540Average$719FlexibilityNo cancel feeOn-time69%

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