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Otopeni Intl

$653+ Cheap flights from St. Louis (STL) to Otopeni Intl (OTP)

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 3/27. Fares are subject to change and may not be available on all flights or dates of travel.
STL — OTP
Oct 30 — Nov 61
Thu 10/30
Thu 11/6
1 adult, Economy
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Cheap flight deals from St. Louis to Otopeni Intl

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Otopeni Intl (OTP). 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 September 30, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$648
(United Airlines)

Popular in

November

Cheapest in

September

Average price

$922
Provider with most accurate pricing for Lambert-St Louis-Bucharest Otopeni Intl flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Bucharest Otopeni Intl flights.
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From Lambert-St Louis to Bucharest Otopeni Intl
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Highest demand for flights based on searches. 10% potential increase in price ($134 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($32 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from St. Louis to Otopeni Intl

Best flights from St. Louis to Otopeni Intl
Discover carefully curated flight deals from St. Louis to Otopeni Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 30, 2025.

This United Airlines deal was found by Cheapflights users on 9/28. 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.
Fri 3/274:50 pmSTL - OTP
1 stop14h 20mUnited Airlines
Tue 3/311:50 pmOTP - STL
2 stops33h 34mUnited Airlines
Deal found 9/28$653
This Lufthansa deal was found by Cheapflights users on 9/28. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/274:50 pmSTL - OTP
1 stop14h 20mLufthansa
Tue 3/316:45 pmOTP - STL
1 stop26h 45mLufthansa
Deal found 9/28$668

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Otopeni Intl 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 September 30, 2025.
Use the filters below to find and compare flights from St. Louis to Bucharest Otopeni Intl Airport that are best for you.

Fly from

St. Louis

Fly to

Otopeni Intl

Route

Depart

Return

Price

St. LouisBucharest

STL - OTP

STLOTP

Lambert-St Louis

Fri 3/27

4:50 pm-2:10 pm

1 stop14h 20m

Bucharest Otopeni Intl

Tue 3/31

1:50 pm-3:24 pm

2 stops33h 34m

$653

St. LouisBucharest

STL - OTP

STLOTP

Lambert-St Louis

Fri 3/27

4:50 pm-2:10 pm

1 stop14h 20m

Bucharest Otopeni Intl

Tue 3/31

6:45 pm-1:30 pm

1 stop26h 45m

$668

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/28

Compare providers for flights from St. Louis to Otopeni Intl

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 St. Louis to Otopeni Intl in September.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust 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 St. Louis-Bucharest Otopeni Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Bucharest Otopeni Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Bucharest Otopeni Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Bucharest Otopeni Intl Airport 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 St. Louis-Bucharest Otopeni Intl Airport 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 St. Louis to Otopeni Intl

Have a flexible travel schedule? Discover the best time to fly to Otopeni Intl from St. Louis 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 St. Louis to Bucharest Otopeni Intl Airport

What is the cheapest time of day to fly from STL to OTP?

Find hourly flight availability from St. Louis to Otopeni Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 30, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 16% on flights from St. Louis to Bucharest Otopeni Intl Airport by exploring options for tickets at noon.

Reviews of airlines servicing Otopeni Intl

Get insights into the airlines that provide service to Otopeni Intl. 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 Otopeni Intl. Reviews last updated September 30, 2025.
Read reviews from past customers who have flown United Airlines and Lufthansa from St. Louis to Bucharest Otopeni Intl Airport. 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
8,931 reviews

Comfort

7.3

Overall

7.4

Entertainment

7.1

Boarding

7.7

Crew

8.1

Food

6.6

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.
United Airlines
7.4
Good
8,931 reviews
United Airlines
7.4
Good
8,931 reviews

Comfort

7.3

Overall

7.4

Entertainment

7.1

Boarding

7.7

Crew

8.1

Food

6.6

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.
Lufthansa
6.8
Okay
7,439 reviews
United Airlines
7.4
Good
8,931 reviews

Comfort

7.3

Overall

7.4

Entertainment

7.1

Boarding

7.7

Crew

8.1

Food

6.6

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.

Related info for your journey

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

  • What airport do you fly from for flights from St. Louis to Bucharest Otopeni Intl?

    Located just 12.7 mi from the city center, Lambert-St Louis is the airport most travelers will use when flying to Bucharest Otopeni Intl from St. Louis. Booking flights from Lambert-St Louis (STL) to Bucharest Otopeni Intl should be relatively easy as there are 0 daily outbound flights to Bucharest Otopeni Intl from 2 different airlines.

  • How long is the flight from St. Louis to Bucharest Otopeni Intl Airport?

    For as low as $653, United Airlines can have you in Bucharest Otopeni Intl Airport from St. Louis in 14h 20m. The distance between St. Louis and Bucharest Otopeni Intl Airport is about 5451 mi.

  • What are the cheapest airlines flying from St. Louis to Bucharest Otopeni Intl Airport round-trip?

    According to our current data, Lufthansa ($772), and United Airlines ($784) offers the cheapest pricing from St. Louis to Bucharest Otopeni Intl Airport. You may be able to fly from St. Louis to Bucharest Otopeni Intl Airport for 30% less than the average price by searching for these airlines.

  • Can I find deals for flights from St. Louis to Otopeni Intl that include hotel bookings?

    Yes. In addition to deals on St. Louis to Otopeni Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Otopeni Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Otopeni Intl.

  • Can I find deals for business class flights from St. Louis to Otopeni Intl?

    Yes. Cheapflights offers flight deals from St. Louis to Otopeni Intl 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 St. Louis to Bucharest Otopeni Intl Airport?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to Bucharest Otopeni Intl Airport (average of $604). Flying from St. Louis to Bucharest Otopeni Intl Airport in June is currently the most expensive (average of $1,128). 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

Traveling to a place near Bucharest Otopeni Intl Airport?

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Otopeni

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Alternative routes for St. Louis to Otopeni Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Springfield to Otopeni Intl flights
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Top 2 airlines flying from St. Louis to Otopeni Intl

Discover the top 2 airlines that operate flights from St. Louis to Otopeni Intl. 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 September 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest$772Average$1,068FlexibilityNo cancel feeOn-time76%
United AirlinesCheapest$784Average$941FlexibilityNo cancel feeOn-time69%

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