$953 Cheap Flights from St. Louis (STL) to Monrovia (ROB)

View $953 flight on Sun, Nov 23, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Monrovia (ROB-Roberts Intl.)

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Cheap Flights from St. Louis to Monrovia (STL-ROB)

Prices were available within the past 7 days and start at $953 for one-way flights and $1,498 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Tue, Apr 21 - Tue, May 19
STL
St. Louis
ROB
Monrovia
$1,498 Roundtrip, found 14 hours ago
$1,498
Roundtrip
found 14 hours ago
Select United flight, departing Tue, Apr 21 from St. Louis to Monrovia, returning Tue, May 19, priced at $1,498 found 14 hours ago
United
Tue, Nov 18 - Mon, Nov 24
STL
St. Louis
ROB
Monrovia
$1,591 Roundtrip, found 3 days ago
$1,591
Roundtrip
found 3 days ago
Select United flight, departing Tue, Nov 18 from St. Louis to Monrovia, returning Mon, Nov 24, priced at $1,591 found 3 days ago
United
Mon, Feb 2 - Fri, Feb 13
STL
St. Louis
ROB
Monrovia
$1,617 Roundtrip, found 1 day ago
$1,617
Roundtrip
found 1 day ago
Select United flight, departing Mon, Feb 2 from St. Louis to Monrovia, returning Fri, Feb 13, priced at $1,617 found 1 day ago
Delta
Mon, Nov 17 - Thu, Nov 27
STL
St. Louis
ROB
Monrovia
$1,620 Roundtrip, found 3 days ago
$1,620
Roundtrip
found 3 days ago
Select Delta flight, departing Mon, Nov 17 from St. Louis to Monrovia, returning Thu, Nov 27, priced at $1,620 found 3 days ago
United
Mon, Feb 2 - Fri, Feb 13
STL
St. Louis
ROB
Monrovia
$1,623 Roundtrip, found 1 day ago
$1,623
Roundtrip
found 1 day ago
Select United flight, departing Mon, Feb 2 from St. Louis to Monrovia, returning Fri, Feb 13, priced at $1,623 found 1 day ago
United
Mon, Feb 2 - Fri, Feb 13
STL
St. Louis
ROB
Monrovia
$1,625 Roundtrip, found 1 day ago
$1,625
Roundtrip
found 1 day ago
Select United flight, departing Mon, Feb 2 from St. Louis to Monrovia, returning Fri, Feb 13, priced at $1,625 found 1 day ago
United
Tue, Apr 21 - Tue, May 19
STL
St. Louis
ROB
Monrovia
$1,673 Roundtrip, found 14 hours ago
$1,673
Roundtrip
found 14 hours ago
Select United flight, departing Tue, Apr 21 from St. Louis to Monrovia, returning Tue, May 19, priced at $1,673 found 14 hours ago
United
Sun, Nov 23 - Thu, Nov 27
STL
St. Louis
ROB
Monrovia
$1,684 Roundtrip, found 3 days ago
$1,684
Roundtrip
found 3 days ago
Select United flight, departing Sun, Nov 23 from St. Louis to Monrovia, returning Thu, Nov 27, priced at $1,684 found 3 days ago
Brussels Airlines
Mon, Feb 2 - Fri, Feb 13
STL
St. Louis
ROB
Monrovia
$1,759 Roundtrip, found 1 day ago
$1,759
Roundtrip
found 1 day ago
Select Brussels Airlines flight, departing Mon, Feb 2 from St. Louis to Monrovia, returning Fri, Feb 13, priced at $1,759 found 1 day ago
American Airlines
Wed, Dec 3 - Wed, Dec 17
STL
St. Louis
ROB
Monrovia
$2,137 Roundtrip, just found
$2,137
Roundtrip
just found
Select American Airlines flight, departing Wed, Dec 3 from St. Louis to Monrovia, returning Wed, Dec 17, priced at $2,137 just found

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB) cost?
Snag a cheap one-way flight from $953 or cheap return flight from $1,498 from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB) 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 Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB)?
The cheapest month to fly from STL to ROB is April, when there's less demand. Off-peak months are often when better flight deals are available between these airports.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB)?
Expedia's filter tool lets you easily compare airlines, flight times and baggage options all in one place. Customize the search to your preferences, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest STL to ROB flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB)?
Nonstop flights from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB) aren't available daily, so you'll have to take a flight with a layover. Explore your options with our filter tool. Enter your travel dates and pick either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to ROB?
Usually you'll find the most flight options available on a Friday. Tuesdays are often the quietest.* But this can change depending on the airline, season 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 Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB)?
Book a flight from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB) that takes off before 3 PM to reduce the likelihood of delays and cancellations. Departures after this hour have a 22% higher chance of being canceled, on average.**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 Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB) last-minute?
Last-minute bookings from STL to ROB are usually more expensive. To secure the best rates, start looking for flights ahead of time. That said, if your travel plans are flexible, you may land a cheap fare right before your journey.
Is it cheaper to book a STL to ROB flight and hotel package?
You'll generally save money by booking a STL to ROB flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's simple to manage everything in one place. After selecting your preferred flights and accommodations, you can add extras like car rentals, tours and activities.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Roberts Intl. Airport (ROB)?
You can usually reschedule or cancel your STL to ROB flight. However, if it's been more than 24 hours since booking, additional charges may apply. Check your airline's policies in your itinerary to see what changes are allowed and whether any costs are involved. You'll also find further details on our Customer Service portal.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Roberts Intl.
Airlines serving
Brussels Airlines, United
Roundtrip price
$1,498
Distance
5410 mi

Book with confidence

St. Louis to Monrovia Flights

The cheapest times to fly from St. Louis to Monrovia

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 St. Louis to Monrovia are during the month of April. You can find some of the cheapest flights from St. Louis to Monrovia with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Monrovia

Sunday is one of the best days to book for cheap flights from St. Louis to Monrovia: 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 St. Louis to Monrovia

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 St. Louis to Monrovia in 2025. You can also book with separate airlines for your outbound and return journeys, from $953 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 St. Louis to Monrovia 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 St. Louis to Monrovia 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.

 

St. Louis to Monrovia Flights
*Available to One Key members.