STL - IDA

$259 Find Cheap Flights from St. Louis to Idaho Falls

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Idaho Falls departing on 3/14. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Idaho Falls

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Idaho Falls, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Idaho Falls, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$365
Multiple Airlines
Sun 2/1Thu 2/5
STL - IDA • 1 stop
Cheapest one-way
$259
United Airlines
Sat 3/14
STL - IDA • 1 stop
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Idaho Falls!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from St. Louis to Idaho Falls (STL-IDA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Idaho Falls that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Idaho Falls

Sun, Feb 1 - Thu, Feb 5
Multiple Airlines Logo
9:32 pm - 2:19 pm
STL
-
IDA
17h 47m1 stop
Multiple Airlines Logo
1:34 pm - 6:44 pm
IDA
-
STL
28h 10m2 stops
$365Multiple Airlines
Sun, Feb 1 - Thu, Feb 5
Multiple Airlines Logo
9:32 pm - 2:19 pm
STL
-
IDA
17h 47m1 stop
Multiple Airlines Logo
1:34 pm - 12:08 pm
IDA
-
STL
21h 34m1 stop
$389Multiple Airlines
Fri, Mar 6 - Wed, Mar 11
United Airlines Logo
5:15 am - 9:56 am
STL
-
IDA
5h 41m1 stop
United Airlines Logo
10:50 am - 4:49 pm
IDA
-
STL
4h 59m1 stop
$406United Airlines
Fri, Mar 6 - Wed, Mar 11
United Airlines Logo
5:15 am - 9:56 am
STL
-
IDA
5h 41m1 stop
United Airlines Logo
10:50 am - 10:59 pm
IDA
-
STL
11h 09m2 stops
$412United Airlines
Mon, Feb 9 - Mon, Feb 16
Alaska Airlines Logo
2:50 pm - 10:59 pm
STL
-
IDA
9h 09m1 stop
Alaska Airlines Logo
8:00 am - 11:59 pm
IDA
-
STL
14h 59m1 stop
$428Alaska Airlines
Sun, Jan 25 - Thu, Jan 29
American Airlines Logo
2:38 pm - 10:36 pm
STL
-
IDA
8h 58m1 stop
American Airlines Logo
2:07 pm - 10:59 pm
IDA
-
STL
7h 52m1 stop
$431American Airlines
Sun, Jan 25 - Thu, Jan 29
United Airlines Logo
8:45 am - 1:30 pm
STL
-
IDA
5h 45m1 stop
United Airlines Logo
10:51 am - 10:58 pm
IDA
-
STL
11h 07m2 stops
$436United Airlines
Sun, Jan 25 - Thu, Jan 29
United Airlines Logo
6:30 am - 1:30 pm
STL
-
IDA
8h 00m2 stops
United Airlines Logo
10:51 am - 10:58 pm
IDA
-
STL
11h 07m2 stops
$442United Airlines
Fri, Mar 6 - Wed, Mar 11
Alaska Airlines Logo
7:00 am - 11:36 pm
STL
-
IDA
17h 36m1 stop
Alaska Airlines Logo
5:20 pm - 1:51 pm
IDA
-
STL
19h 31m1 stop
$452Alaska Airlines
Sat, Jan 24 - Tue, Jan 27
United Airlines Logo
8:45 am - 1:30 pm
STL
-
IDA
5h 45m1 stop
United Airlines Logo
2:40 pm - 8:58 pm
IDA
-
STL
5h 18m1 stop
$546United Airlines
Booking Insights

KAYAK's insights & trends for St. Louis to Idaho Falls flights

Get data-powered insights and trends into flights from St. Louis to Idaho Falls to help you find the cheapest flights, the best time to fly and much more.

Which airlines fly non-stop between St. Louis and Idaho Falls?

Airline and price data is aggregated from results in KAYAK’s search results from the last 2 weeks for round-trip flights from St. Louis to Idaho Falls.

There are 2 airlines that fly nonstop from St. Louis to Idaho Falls. They are Delta and United Airlines. The cheapest airline for this route is Delta, with the best round-trip deal found costing $192. On average, the best prices for this route can be found at Delta.

Good to know

Low seasonAugust
Cheapest flight$259
Best time to beat the crowds with an average 27% drop in price.
Most popular time to fly and prices are also 5% lower on average.
Flight from St. Louis to Idaho Falls

When to book flights from St. Louis to Idaho Falls

Are your dates flexible? Find out the best times to travel from St. Louis to Idaho Falls based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from St. Louis to Idaho Falls

  • What is the cheapest flight from St. Louis to Idaho Falls?

    In the last 3 days, the lowest price for a flight from St. Louis to Idaho Falls was $259 for a one-way ticket and $365 for a round-trip.

  • Do I need a passport to fly between St. Louis and Idaho Falls?

    No

  • Which airports will I be using when flying from St. Louis to Idaho Falls?

    St. Louis and Idaho Falls are both served by 1 main airport. You will leave St. Louis from Lambert-St Louis and will be arriving at Idaho Falls Fanning Field.

  • Which aircraft models fly most regularly from St. Louis to Idaho Falls?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from St. Louis to Idaho Falls?

    SkyTeam, and Star Alliance are the airline alliances operating flights between St. Louis and Idaho Falls, with SkyTeam being the most commonly used for this route.

  • Which is the best airline for flights from St. Louis to Idaho Falls, Delta or United Airlines?

    The two airlines most popular with KAYAK users for flights from St. Louis to Idaho Falls are Delta and United Airlines. With an average price for the route of $384 and an overall rating of 7.9, Delta is the most popular choice. United Airlines is also a great choice for the route, with an average price of $578 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from St. Louis to Idaho Falls?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Idaho Falls.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Idaho Falls?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Idaho Falls from St. Louis is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Idaho Falls?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Idaho Falls with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and IDA can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Idaho Falls?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Idaho Falls from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airlines flying from St. Louis to Idaho Falls

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Idaho Falls. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Idaho Falls? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
DeltaOverall score based on 8039 reviews
8.1Boarding
7.2Food
7.9Comfort
8.5Crew
7.8Entertainment
Airline reviews

Food is basically Sun Chips, cookies or Cheezits. I had an exit row seat so I had plenty of room. The crew was very nice and efficient. Pilot kept us informed. Pretty good flight.

8.0 ExcellentG, Jan 2026
FLL - ATL
Read more Delta reviews

Food is basically Sun Chips, cookies or Cheezits. I had an exit row seat so I had plenty of room. The crew was very nice and efficient. Pilot kept us informed. Pretty good flight.

Air travel sucks. It continues to be awful for all airlines. No shame on delta alone.

It was Delta, but the flight attendants were stressful and disrespectful. I am a diamond member a travel weekly. I have not had a negative thing to share in quite some time. But this was noticeable.

Comfort Plus seat 11E seemed smaller than prior flights. The movie selection is good. Watched most of the most recent Tron movie. I'll watch the remaining part later as my movie is saved in the Delta Seatback Experience.

Flight was late from Newark to Atlanta, I asked flight attendant to please let my family of 3 out first when we landed to Atlanta because we were late for our connecting flight to Quito. She didn't and we were late for 5 minutes we couldn't board the plane and spend hours trying to get another flight with customer service for the next day.

I really liked the legroom. I am 6’4”.a at For some reason our seats were not together and using the app to fix it didn’t work. Passengers were nice enough to move for us but you should absolutely ensure a parent sits with their child.

Late delayed flight delays boarding and delays leaving and delays on arrival too. Cramped plane no room no food.

DTW line is too long. The flights from DTW to BWI are always delayed for unknown reasons.

Delta canceled our flight and we had to scramble to find another airline to get home. Phoenix is not a delta hub so they didn’t have another plane. It would have been a red eye though Salt Lake City. Getting in at 5am. No bueno.

This flight was no comparison to our prior flight. I'm thinking it all has to do with the age of the aircraft.

Teeny tiny bathrooms, crew was not realistic about when we'd arrive.

Check-in, boarding and the flight from Phoenix to Houston was quick and easy. The flight from Houston to Shreveport was delayed 5 hours. It was frustrating but I think United handled it the best they could.

They lost my luggage, so, not happy. The crew was nice but my suitcases never made it, still trying to find out what happened!

The staff was hospitable and professional. The seat had a bit of wear. The winner shade was stuck 1/4 open. I received the best of both worlds. The morning sun was able to come in and blind the screen i was trying to use while at the same time it was too low to look out and enjoy the view. Rather embarrassing for a 1st class ticket.

Perfect flight. Smooth flight. Arrived 20 minutes early at destination. Excellent service.

The flights were on time which was great give. It was holiday travel season and there’d been some weather issues. The only complaint and this is every time with United is the terrible seat design. The head rest is not built for comfort and having my neck bent forward for a cross country trip reminded me while I try not to take United flights as a rule.

I’m so sorry, I can’t remember her name, I believe it was Dimpti. She was stellar, also a mature Asian flight attendant, lots of flowers in her hair, just as amazing! But literally the crew was AWESOME . Only downside is there weren’t any charging outlets. Maybe I needed to ask a flight attendant , but it would’ve been nice to have one easily accessible.

The flight was delayed by two de-icings. The seatbelt did not work correctly. It did not stay tight.

Everything was absolutely wonderful from check in to baggage claim. Staff was very professional and sweet. Will definitely recommend United to family and friends.

Sitting on the runway after we land for almost two hours! Not sure if we should blame United or Just Dumpy Vance.

Everything you need to know for your flight from St. Louis to Idaho Falls

Information on your arrival and departure airports