Cheap flights To Union (STL) from $28

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Cheap Flights to Union from $28 One Way, $57 Round Trip

Prices found within past 7 days. Prices and availability subject to change. Additional terms may apply.

Sat, Apr 25 - Sat, May 2
DEN
Denver Intl.
STL
Lambert-St. Louis Intl.
$57 Roundtrip, found 2 hours ago
$57
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Sat, Apr 25 from Denver Intl. to Lambert-St. Louis Intl., returning Sat, May 2, priced at $57 found 2 hours ago
Sat, Apr 18 - Sat, Apr 25
DEN
Denver Intl.
STL
Lambert-St. Louis Intl.
$57 Roundtrip, found 4 hours ago
$57
Roundtrip
found 4 hours ago
Select Frontier Airlines flight, departing Sat, Apr 18 from Denver Intl. to Lambert-St. Louis Intl., returning Sat, Apr 25, priced at $57 found 4 hours ago
Wed, Mar 18 - Sat, May 9
DEN
Denver Intl.
STL
Lambert-St. Louis Intl.
$63 Roundtrip, found 2 days ago
$63
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, Mar 18 from Denver Intl. to Lambert-St. Louis Intl., returning Sat, May 9, priced at $63 found 2 days ago
Tue, Mar 24 - Tue, Mar 31
ATL
Hartsfield-Jackson Atlanta Intl.
STL
Lambert-St. Louis Intl.
$66 Roundtrip, found 6 hours ago
$66
Roundtrip
found 6 hours ago
Select Frontier Airlines flight, departing Tue, Mar 24 from Hartsfield-Jackson Atlanta Intl. to Lambert-St. Louis Intl., returning Tue, Mar 31, priced at $66 found 6 hours ago
Wed, Apr 15 - Wed, Apr 22
ATL
Hartsfield-Jackson Atlanta Intl.
STL
Lambert-St. Louis Intl.
$67 Roundtrip, found 8 hours ago
$67
Roundtrip
found 8 hours ago
Select Frontier Airlines flight, departing Wed, Apr 15 from Hartsfield-Jackson Atlanta Intl. to Lambert-St. Louis Intl., returning Wed, Apr 22, priced at $67 found 8 hours ago
Wed, Mar 18 - Wed, Mar 18
DEN
Denver Intl.
STL
Lambert-St. Louis Intl.
$69 Roundtrip, found 15 hours ago
$69
Roundtrip
found 15 hours ago
Select Frontier Airlines flight, departing Wed, Mar 18 from Denver Intl. to Lambert-St. Louis Intl., returning Wed, Mar 18, priced at $69 found 15 hours ago
Sat, May 9 - Fri, May 15
DEN
Denver Intl.
STL
Lambert-St. Louis Intl.
$70 Roundtrip, found 6 hours ago
$70
Roundtrip
found 6 hours ago
Select Frontier Airlines flight, departing Sat, May 9 from Denver Intl. to Lambert-St. Louis Intl., returning Fri, May 15, priced at $70 found 6 hours ago
Thu, Apr 30 - Sun, May 3
MCO
Orlando Intl.
STL
Lambert-St. Louis Intl.
$118 Roundtrip, found 6 days ago
$118
Roundtrip
found 6 days ago
Select Frontier Airlines flight, departing Thu, Apr 30 from Orlando Intl. to Lambert-St. Louis Intl., returning Sun, May 3, priced at $118 found 6 days ago
Mon, Apr 27 - Mon, May 4
DFW
Dallas-Fort Worth Intl.
STL
Lambert-St. Louis Intl.
$136 Roundtrip, found 1 day ago
$136
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Mon, Apr 27 from Dallas-Fort Worth Intl. to Lambert-St. Louis Intl., returning Mon, May 4, priced at $136 found 1 day ago
Thu, Apr 30 - Thu, May 7
LGA
LaGuardia
STL
Lambert-St. Louis Intl.
$160 Roundtrip, found 1 day ago
$160
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Thu, Apr 30 from LaGuardia to Lambert-St. Louis Intl., returning Thu, May 7, priced at $160 found 1 day ago

Union Flight Information

Traveling To
Union
Destination Airport IATA Code
STL
Number of Airlines Serving
Airlines
Frontier Airlines
Flight Price
$57
Earliest Departing Flight
Latest Departing Flight

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Union economy flight packages

Price found within the past 48 hours. Click for updated prices.
The Wildwood Hotel
3.5-star property

The Wildwood Hotel

Apr 9 - Apr 14

5 night stay

Milwaukee (MKE) to St. Louis (STL)

Southwest Airlines • Roundtrip • Coach
Save 100% on your flight
Price was $944, price is now $532 per person
$532
per person
found 1 day ago
Angad Arts Hotel St. Louis, Tapestry Collection by Hilton
4.0-star property

Angad Arts Hotel St. Louis, Tapestry Collection by Hilton

Apr 9 - Apr 14

5 night stay

Milwaukee (MKE) to St. Louis (STL)

Southwest Airlines • Roundtrip • Coach
Price was $893, price is now $669 per person
$669
per person
found 1 day ago
The Cheshire
4.0-star property

The Cheshire

Apr 9 - Apr 14

5 night stay

Milwaukee (MKE) to St. Louis (STL)

Southwest Airlines • Roundtrip • Coach
Price was $909, price is now $692 per person
$692
per person
found 1 day ago
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Union

Start your search for cheap flights to Union on Orbitz. Orbitz is where you will discover guaranteed low prices on Union flights, as well as all of the following conveniences:

Travel Updates on Your Mobile Device

Orbitz offers cutting-edge mobile tools for your smartphone. Whether you own an iPhone or an Android phone, you can benefit from Orbitz’s flight status updates and even book your future Union flights. You can also review and reserve hotel rooms for when your Union flights land and see other special offers.

Low Prices Guaranteed on Flights to Union

Orbitz offers large discounts on a wide range of Union flights. Through our easy-to-use site, you can find, plan, and reserve your desired flights to Union while taking advantage of the lowest fares around.

Customer Care When You Need It

Orbitz is dedicated to making your flight booking experience as stress-free as possible. If you need to cancel your reservation, you can do so at your own convenience by going to the Orbitz website. If you need to change your flights to Union to another time or date, you can contact our customer service representatives by phone, and they help you make the flight adjustments you need.

Loyalty Program Participation Opportunities

Orbitz lets you add your loyalty or frequent flyer account numbers when you book qualifying flights to Union. So don’t worry about missing out on earning miles or points simply because you aren’t booking with the airline directly. You can save on your flights, and rack up miles too.

Frequently asked questions

Which airlines fly to Union?
With 20 airlines to pick from, finding the ideal flight that suits your travel dates and budget will be a breeze. Lambert-St. Louis Intl. Airport (STL) is a major gateway to Union and where you'll likely be touching down. These well-known international airlines are ready to take you there:

  • Air Canada - 35 flights to Union per month
  • Frontier Airlines - 17 flights to Union per month
  • Lufthansa - 3 flights to Union per month

How much is a flight to Union?
If you're hunting down a return flight, fares ranged from $57 to $160 this week. The most affordable prices for one-way tickets were $28, originating from Denver (DEN).
How to book the cheapest flight to Union?
Scoring cheap flights to Union is as easy as booking your ticket with Orbitz. But if you'd love to make sure you're nabbing the best flight deals around, here are a few tips your budget will love:

  • Consider departing from or arriving at nearby airports for a cheaper fare. Enter your preferred departure and arrival points in the form fields, then select the 'Nearby airports' function below. It will list the available options.
  • If your plans aren't etched in stone, click on the 'Show flexible dates' link to see the flight deals across different departure dates. Go with any suitable cheaper fare that pops up.
  • Hit 'Show options' to fine tune your search results. You can pick your preferred seating class and airline here. Under 'Sort & Filter' to the left, you can even specify whether you'd like to fly in the morning, afternoon or evening.
  • Book your airfare as soon as you've decided on your travel dates. While it does happen now and then, airline tickets rarely get more affordable as your date of departure gets closer.
  • Consider combining your flights, hotels and car rentals into one convenient package deal to stretch your budget even further.
  • Don't travel during the busy season if you can. By avoiding summer and school vacations, you can make amazing savings on your airfare.

What is the best time to book a flight to Union?
Snap up a bargain and book your seats to Union in January. If you've missed this month, fear not. February and August often have low airfares as well. Just make sure you don't snooze on a sale — cheap flights come and go in the blink of an eye!
What day of the week is the cheapest to book a flight to Union?
Make a booking on a Tuesday, Wednesday or Saturday. Typically, these are the cheapest days of the week to purchase airfares to Union. The vacation of your dreams starts with a great flight deal!
What is the cheapest day of the week to fly to Union?
If you're looking for cheap flights to Union, leave earlier in the week. Orbitz data from 2020 shows Monday is the cheapest day to jet off, followed by Tuesday. Saturday has the most expensive fares, so avoid this day and do your bank account a favor.
What is the cheapest month to fly to Union?
To book cheap flights to Union, you should pack your bags and take off in August. Orbitz data has found that this is generally the best month to save loads on your fare. If you want to jet to Union in June, be aware that this is the least affordable time of year to take a trip.
Which airlines allow free cancellation?
When searching for flights on Orbitz, click on "Filter by flexible change policies." This filter will show you all the airlines offering free cancellation and no change fees. Relax knowing that if things change, your flight can too.
What do I need for the flight to Union?
There's nothing more enjoyable than flying off to a cool new destination, but it's wise to be prepared. This list of useful tips will help get your journey started on the right foot:

  • Before you step foot on the plane, you'll need to show proof of identification, such as a passport. You'll also need your boarding pass. If you're traveling with the kids, check with your airline about which documents they may need.
  • To keep you busy on your short trip to Union, download some new music or stock up the audiobook library on your tablet. Food can also be a welcome distraction while in the air, so maybe even bring some light snacks.
  • It can get very cool on the plane. If you don't want to shiver your way through the flight, dress in layers.

How do I get cheap first-class/business deals to Union?
Smart travelers know how to find first or business-class airfares to Union without the steep price tag. You can do the same with these helpful tips:

  • Be more flexible with your travel dates and hold out for deals on first or business-class airfares.
  • A lot of low-cost airlines nowadays offer superb business or premium-class seating without the pricey fees.
  • Make a bid for an upgrade. Some carriers hold online auctions that let you put down a price for a seat up the front. You may also be able to upgrade with points earned through a loyalty program.

What is the best time to go to Union?
If you want to immerse yourself in the culture of Union in the busy season, April, May and June are the prime months to visit. June 20 signals the start of summertime in the Northern Hemisphere and is a fantastic time to travel if you delight in the open air. During this time of year, average daily temperatures typically range from 65 ºF to 90 ºF.

More to Explore

Fare, taxes & fees: Fares include all taxes and fees, except baggage fees. Rates shown reflect fares found by other Orbitz users over the past 7 days. Due to rapidly changing airline prices & seat availability, these fares may no longer be available.

Refunds/changes/cancellations: Itinerary changes, if permitted for the fare, will have a $30 service fee charged by Orbitz. Additional airline charges may apply.

Other conditions: Schedules, fares and rules are subject to change without notice. Seats are limited and may not be available on all flights/dates or in all markets. Lower fares may be available. Fares will not be honored retroactively or in exchange for any wholly/partially unused ticket. Tickets are non-transferable and non-refundable. Fare rules are provided for the selected itinerary before booking.