Cheap flights from Idaho Falls to St. Louis (IDA - STL) from $357

This is the cheapest one-way flight price, found on 9/19. Prices may vary by date and flight preferences.
IDA — STL
Sep 26 — Oct 31

How to find the cheapest flight from Idaho Falls (IDA) to St. Louis (STL)

All the information you need to plan the best IDA to STL flight in 2023: compare Idaho Falls to St. Louis flight prices with the expected peak season, weather and rainfall in St. Louis.

Popular in

June

Cheapest in

October

Average price

$490

Round-trip from

$299
High demand for flights, 47% potential price rise
Best time to find cheap flights, 47% potential price drop
Average for round-trip flights in September 2023
From Idaho Falls Fanning Field to Lambert-St Louis

IDA - STL

Price

$299 - $477

STL

Temperature

32 - 80.6 °F

STL

Rainfall

2.2 - 4.7 inches

What is the cheapest month to fly from Idaho Falls to St. Louis?

Our data shows that October tends to be the cheapest month to fly to St. Louis from Idaho Falls. Users have commonly found prices around $664 for the month, but tickets can be as low as $355. Due to multiple factors, prepare for potentially higher prices in June.

When is the cheapest time to fly from Idaho Falls to St. Louis (IDA - STL)?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Idaho Falls to St. Louis as you normally would.

Cheap Delta flights from Idaho Falls to St. Louis

Peruse some of the lowest-priced Delta flights we've found from Idaho Falls to St. Louis. Be sure to come back soon if the deals available don't appeal to you at this time.

Cheap United Airlines flights from Idaho Falls to St. Louis

To aid your search, here are some of the cheapest United Airlines flights we've found from Idaho Falls to St. Louis. Ensure the flight price, dates, time, and airline match your criteria before you book.

Cheap Idaho Falls to St. Louis flights in September & October 2023

The best prices found for IDA to STL flights for September, October
Scroll through some of the best deals on flights from Idaho Falls to St. Louis in 2023. Check back regularly for other flight deals.

Idaho Falls to St. Louis 2023 flight deals

Cheap flights to St. Louis from Idaho Falls found for this year
Scroll through some of the best deals on flights from Idaho Falls to St. Louis in 2023. Check back regularly for other flight deals.

Find flights from Idaho Falls to St. Louis within your budget

Use the slider to find flights from Idaho Falls to St. Louis that fit your budget.

Fly from

Any airport

Fly to

Any airport

Budget

$357 - $706

Route

Depart

Return

Price

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 10/23

1 stop5h 14m

Lambert-St Louis

Wed 10/25

1 stop4h 47m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 10/23

1 stop5h 14m

Lambert-St Louis

Wed 10/25

1 stop5h 06m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Sat 12/16

2 stops12h 47m

Lambert-St Louis

Tue 12/19

1 stop4h 55m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Sat 12/16

1 stop5h 58m

Lambert-St Louis

Tue 12/19

1 stop4h 55m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 10/23

2 stops12h 47m

Lambert-St Louis

Wed 10/25

1 stop5h 06m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 10/23

2 stops12h 47m

Lambert-St Louis

Tue 10/24

1 stop5h 06m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Mon 10/23

2 stops17h 13m

Lambert-St Louis

Wed 10/25

2 stops24h 48m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Sun 12/17

1 stop4h 47m

Lambert-St Louis

Wed 12/20

1 stop16h 26m

Idaho Falls Fanning FieldLambert-St Louis

IDA - STL

IDASTL

Idaho Falls Fanning Field

Sat 12/16

2 stops20h 21m

Lambert-St Louis

Tue 12/19

2 stops11h 21m

Flights are sorted by cheapest first

Deals found on 9/19

Reviews of airlines servicing St. Louis

Read through reviews of airlines operating flights from Idaho Falls to St. Louis, such as Delta and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
3,017 reviews

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Overall

7.9

Crew

8.5

Reviews

1 / 10

Even if you have delta comfort plus, they will move your overhead bag. One of the perks for upgrading is that you have dedicated space for your carry on with comfort plus with delta. They moved my carry on luggage (3) compartments back and put in bags for other passengers that should have gone under their respective seats. When deboarding the plane, there was no help from anyone to retrieve my luggage back several rows. Delta is turning into pure garbage.

Delta
7.9
Good
3,017 reviews
Delta
7.9
Good
3,017 reviews

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Overall

7.9

Crew

8.5

Reviews

1 / 10

Even if you have delta comfort plus, they will move your overhead bag. One of the perks for upgrading is that you have dedicated space for your carry on with comfort plus with delta. They moved my carry on luggage (3) compartments back and put in bags for other passengers that should have gone under their respective seats. When deboarding the plane, there was no help from anyone to retrieve my luggage back several rows. Delta is turning into pure garbage.

United Airlines
7.4
Good
1,887 reviews
Delta
7.9
Good
3,017 reviews

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Overall

7.9

Crew

8.5

Reviews

1 / 10

Even if you have delta comfort plus, they will move your overhead bag. One of the perks for upgrading is that you have dedicated space for your carry on with comfort plus with delta. They moved my carry on luggage (3) compartments back and put in bags for other passengers that should have gone under their respective seats. When deboarding the plane, there was no help from anyone to retrieve my luggage back several rows. Delta is turning into pure garbage.

Related info for your journey

Useful info, stats and facts about Idaho Falls to St. Louis flights.

Can I find flights from Idaho Falls to St. Louis for under $400 on Cheapflights?

Yes, there are multiple flights from Idaho Falls to St. Louis for under $400. The cheapest flight booked recently is on Delta for just $357, but on average you can expect to pay $609.

What are the cheapest airlines flying from Idaho Falls to St. Louis round-trip?

Cheapflights users have booked flights from Idaho Falls to St. Louis round-trip from $357. Another airline that can offer you cheap pricing is United Airlines. Users have found that Delta is 46% cheaper than the other options available to this destination.

What does IDA to STL mean?

IDA and STL are unique codes to identify airports used in the aviation industry. They are defined by IATA (International Air Transport Association) and are commonly called IATA codes. IDA to STL refers to a flight route from Idaho Falls Fanning Field Airport to Lambert-St Louis Airport.

Top airline flying from Idaho Falls to St. Louis

The chart below displays the airlines Cheapflights users traveling from Idaho Falls to St. Louis choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$497Average$721FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
100% Free
Cheapflights is completely free to use, so you can start saving the moment you arrive.
Book with Flexibility
Our users can plan ahead with confidence and find flights with no change fees
Travel Smart
Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.