Cheap flights from St. Louis to Belfast from $337
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Belfast departing on 7/27. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from St. Louis to Belfast Intl Airport
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest day to depart on your flight to Belfast Intl Airport?
The cheapest day to depart on your flight to Belfast Intl Airport is on a Tuesday when prices can be found for as low as $674. This is often the case because there is less demand to fly during this day of the week. When flying out on a Wednesday, the most expensive travel day of the week, you can expect to see flight prices from St. Louis to Belfast Intl Airport for around $870.
What is the cheapest time of day to depart on your flight to Belfast Intl Airport?
In the afternoon is the cheapest time of day to fly from St. Louis to Belfast Intl Airport when you can find flight prices for as low as $785. Flying to Belfast Intl Airport in the afternoon is an ideal time because this is during off-peak travel hours. In contrast, the most expensive time of day to depart to Belfast Intl Airport is at noon when prices are around $1,429.
When to book flights from St. Louis to Belfast Intl Airport
Cheap St. Louis to Belfast Intl Airport (STL to BFS) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Belfast Intl Airport
How far is Lambert-St Louis to Belfast Intl by plane?
Belfast Intl is 3879.0 mi away from Lambert-St Louis. A reasonable flight in good conditions will take 17h 00m.
When did momondo last update prices for flights from Lambert-St Louis Airport to Belfast Intl Airport?
Prices for flights from Lambert-St Louis Airport to Belfast Intl Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Belfast Intl Airport?
As of June 2025, there is 1 operator available to choose from for flights from Lambert-St Louis Airport to Belfast Intl Airport.
How old do you have to be to fly from Lambert-St Louis Airport to Belfast Intl Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Lambert-St Louis Airport to Belfast Intl Airport.
What documentation or ID do you need to fly to Belfast Intl Airport?
The travel and health documents required for your trip to Belfast Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Belfast Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular airline from St. Louis to Belfast Intl Airport?
Based on momondo bookings for flights between St. Louis and Belfast Intl Airport, the leading airline is American Airlines, making up 100% of the total bookings.
Best airlines flying from St. Louis to Belfast Intl Airport
Compare and see reviews for airlines that fly from St. Louis to Belfast Intl Airport with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $658 | Free Cancellation | Rating 7.2 10,000 reviews |
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Why should I use momondo to find a flight deal from St. Louis to Belfast?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Belfast. momondo saves you time and could save you money on your trip.
Can I find flights from St. Louis to Belfast with flexible booking policies on momondo?
All flight searches from St. Louis to Belfast on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from St. Louis to Belfast?
Once all potential St. Louis to Belfast flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from St. Louis to Belfast right now. Can momondo alert me if prices change?
If you are not ready to book a flight from St. Louis to Belfast now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Belfast and let you know when they change.