Cheap flights from St. Louis to Belfast from $749
This is the cheapest round-trip flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Belfast departing on 9/13. 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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British Airways flights from St. Louis to Belfast
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Aer Lingus flights from St. Louis to Belfast
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How to get the cheapest flight ticket from St. Louis to Belfast
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?
The cheapest day to depart from St. Louis to Belfast is on a Tuesday when prices can be found for as low as $674. 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 for around $870.
What is the cheapest time of day to depart on your flight to Belfast?
Our data shows that the cheapest St. Louis to Belfast flights are usually those with departure times in the afternoon. Our users have found flights to Belfast in the afternoon for as low as $785. Try not to purchase tickets at noon because they tend to be around $1,429. Of course, these prices can vary depending on the time of year and what airport you fly to.
Cheap St. Louis to Belfast flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Belfast
How far is Lambert-St Louis to Belfast by plane?
The straight-line distance from Lambert-St Louis to Belfast is 3891.1 mi. Flights usually cover this in 14h 50m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Lambert-St Louis Airport to Belfast?
Prices for flights from Lambert-St Louis Airport to Belfast are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Belfast?
As of April 2025, there is 1 operator available to choose from for flights from Lambert-St Louis Airport to Belfast.
How old do you have to be to fly from Lambert-St Louis Airport to Belfast?
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.
What documentation or ID do you need to fly to Belfast?
The travel and health documents required for your trip to Belfast 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. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
Best airlines flying from St. Louis to Belfast
Compare and see reviews for airlines that fly from St. Louis to Belfast with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $658 | Free Cancellation | Rating 7.2 10,000 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from St. Louis to Belfast?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Belfast from St. Louis.
Can I find flights from St. Louis to Belfast with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for St. Louis to Belfast flights to just show those with 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?
Yes momondo offers price alerts on flights to Belfast from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.