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Flights from Ontario to St. Louis
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Flights from Ontario to St. Louis Starting at NZD 81

We've found these cheap flights for you. You can book one-way or return flight tickets.

  • One way
  • Round-trip
      • ONT00:59
        6h 7m
        1 stop
        STL09:06
        Mon, Apr 7|Ontario - St. Louis|Frontier Airlines
        NZD 81NZD 136
        40% OFF
        40% OFF
        NZD 136NZD 81

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Mon, Apr 7, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 81 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Mon, Feb 24|Ontario - St. Louis|Frontier Airlines
        NZD 84NZD 136
        38% OFF
        38% OFF
        NZD 136NZD 84

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Mon, Feb 24, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 84 including taxes and charges.

      • ONT21:06
        18h 30m
        1 stop
        STL17:36
        Mon, Mar 3|Ontario - St. Louis|Frontier Airlines
        NZD 93NZD 136
        32% OFF
        32% OFF
        NZD 136NZD 93

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Mon, Mar 3, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 93 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Wed, Feb 19|Ontario - St. Louis|Frontier Airlines
        NZD 97
        NZD 97

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Wed, Feb 19, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 97 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Sat, Feb 15|Ontario - St. Louis|Frontier Airlines
        NZD 97
        NZD 97

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Sat, Feb 15, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 97 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Wed, Feb 12|Ontario - St. Louis|Frontier Airlines
        NZD 98
        NZD 98

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Wed, Feb 12, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 98 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Wed, Mar 5|Ontario - St. Louis|Frontier Airlines
        NZD 100
        NZD 100

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Wed, Mar 5, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 100 including taxes and charges.

      • ONT00:59
        6h 7m
        1 stop
        STL09:06
        Wed, Apr 9|Ontario - St. Louis|Frontier Airlines
        NZD 101
        NZD 101

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Wed, Apr 9, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 101 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Mon, Mar 10|Ontario - St. Louis|Frontier Airlines
        NZD 101
        NZD 101

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Mon, Mar 10, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 101 including taxes and charges.

      • ONT00:59
        6h 17m
        1 stop
        STL09:16
        Wed, Mar 12|Ontario - St. Louis|Frontier Airlines
        NZD 101
        NZD 101

        Choose Frontier Airlines flights from Ontario to St. Louis. The one-way connecting flight with Frontier Airlines departs from Ontario International Airport on Wed, Mar 12, arriving at St. Louis Lambert International Airport. One-way Prices start from NZD 101 including taxes and charges.

      • ONT01:00 pm
        3h 5m
        Nonstop
        STL02:00 pm
        Sat, Feb 15|Ontario - St. Louis|Frontier Airlines
        Find More Flights
        Find More Flights

Crossed out prices are calculated based on the average price of the corresponding route on Trip.com.

Los Angeles to St. Louis flight time & flight schedules

Flight info.
Departure
Arrival
Weekly Schedule

  1. F91500

    Frontier Airlines

    00:59

    ONT

    2.3h

    04:17

    DEN

    SMTWTFS
    Search

  2. F93302

    Frontier Airlines

    06:00

    DEN

    2.1h

    09:09

    STL

    SMTWTFS

  3. F92232

    Frontier Airlines

    10:52

    ONT

    1.2h

    12:04

    LAS

    SMTWTFS
    Search

  4. F93108

    Frontier Airlines

    15:39

    LAS

    3.4h

    21:05

    STL

    ---WT--

  5. F91262

    Frontier Airlines

    12:16

    ONT

    2.3h

    15:35

    DEN

    SMTW-FS
    Search

  6. F93302

    Frontier Airlines

    06:00

    DEN

    2.1h

    09:09

    STL

    SMTWTFS

  7. F91358

    Frontier Airlines

    14:42

    ONT

    1.2h

    15:53

    LAS

    SMTWTFS
    Search

  8. F91994

    Frontier Airlines

    00:59

    LAS

    2.0h

    03:59

    DEN

    --TWTF-

  9. F93302

    Frontier Airlines

    06:00

    DEN

    2.1h

    09:09

    STL

    SMTWTFS

  10. F91358

    Frontier Airlines

    14:42

    ONT

    1.2h

    15:53

    LAS

    SMTWTFS
    Search

  11. F92430

    Frontier Airlines

    00:59

    LAS

    1.9h

    03:54

    DEN

    SMTWTFS

  12. F93302

    Frontier Airlines

    06:00

    DEN

    2.1h

    09:09

    STL

    SMTWTFS

  13. F91358

    Frontier Airlines

    14:42

    ONT

    1.2h

    15:53

    LAS

    SMTWTFS
    Search

  14. F92018

    Frontier Airlines

    06:00

    LAS

    3.2h

    11:10

    STL

    SMTWTFS

  15. F92908

    Frontier Airlines

    21:19

    ONT

    2.3h

    00:37

    DEN

    ---WT--
    Search

  16. F93302

    Frontier Airlines

    06:00

    DEN

    2.1h

    09:09

    STL

    SMTWTFS

  17. F94206

    Frontier Airlines

    22:39

    ONT

    1.3h

    23:59

    LAS

    SMTWTFS
    Search

  18. F93108

    Frontier Airlines

    15:39

    LAS

    3.4h

    21:05

    STL

    ---WT--

  19. F94206

    Frontier Airlines

    22:39

    ONT

    1.3h

    23:59

    LAS

    SMTWTFS
    Search

  20. F92018

    Frontier Airlines

    06:00

    LAS

    3.2h

    11:10

    STL

    SMTWTFS
Find more flights and airlines

Find the best time to fly from Ontario to St. Louis

We monitor flight fares to help you find the best deals effortlessly

Displayed prices are calculated based on the cheapest average weekly prices of the corresponding route on Trip.com.

FAQ

  • When are flight tickets from Ontario (ONT) to St. Louis (STL) the cheapest?

    Airlines adjust prices for flights from Ontario to St. Louis based on the departure date and time of your selection. By analyzing data from all airlines, we've discovered that on Trip.com, you can find the lowest flight prices on Tuesdays, Wednesdays, and Saturdays.

  • How much do flights from Ontario (ONT) to St. Louis (STL) cost?

    According to Trip.com's data, the lowest price is around NZD 509.

  • What is the transportation method from the main airport to downtown in St. Louis?

    • The distance from St. Louis Lambert International Airport to downtown is about 20 km. It takes about 40 minutes by taxi.

How to find a cheap flight from Ontario to St. Louis

Wait until the last minute and flight costs are often sky-high. Plan ahead, book the right way, and your savings can soar. We have loads of saving tips to help you find a cheap flight from Ontario to St. Louis. Book your flights at the right time and save more.
1
Book Early
Once prices are gone, they're gone. Lock in deals while you can!
2
Compare Flight Prices
Compare prices on travel agency and airline websites.
3
Look Out for Deals
Check airline and travel agency websites for latest flight deals
4
Check One-way Fares
Buying two cheap one-way flights can sometimes be a better deal than a round-trip.
5
Try Different Dates
Flying during the week, early in the morning, or late at night can help save money.
6
Use the Trip.com App
Save up to £10 per person when booking your flights on Trip.com

Flight Information from Ontario to St. Louis

Cheapest nonstop flight priceNZD 81
Cheapest round-trip ticket priceNZD 353
Off-season for travelJanuary
Peak season for travelDecember
Flight distance10,023.47 km
Popular airlineFrontier Airlines

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