American Airlines flights from Chicago to Ontario

Recent searches for flights from Chicago to Ontario

Sep 2026
From$297*
Updated: 10 hours ago
Round tripIEconomy
Oct 2026
From$297*
Updated: 10 hours ago
Round tripIEconomy
Nov 2026
From$297*
Updated: 10 hours ago
Round tripIEconomy
cmp-daily-histogram-bars-legend-min-price-aria-label $297
cmp-daily-histogram-bars-legend-max-price-aria-label $672
Displaying fares for September-2026
  • ORD–ONT, 09/08/26 – 09/15/26: From $672
    08

    Tu

    SEP

  • ORD–ONT, 09/09/26 – 09/16/26: From $297
    09

    We

  • ORD–ONT, 09/10/26 – 09/17/26: From $297
    10

    Th

  • ORD–ONT, 09/11/26 – 09/18/26: From $297
    11

    Fr

  • ORD–ONT, 09/12/26 – 09/19/26: From $297
    12

    Sa

  • ORD–ONT, 09/13/26 – 09/16/26: From $297
    13

    Su

  • ORD–ONT, 09/14/26 – 09/21/26: From $637
    14

    Mo

  • ORD–ONT, 09/15/26 – 09/22/26: From $297
    15

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  • ORD–ONT, 09/16/26 – 09/23/26: From $297
    16

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  • ORD–ONT, 09/17/26 – 09/24/26: From $297
    17

    Th

  • ORD–ONT, 09/18/26 – 09/25/26: From $427
    18

    Fr

  • ORD–ONT, 09/19/26 – 09/26/26: From $297
    19

    Sa

  • ORD–ONT, 09/20/26 – 09/27/26: From $368
    20

    Su

  • ORD–ONT, 09/21/26 – 09/28/26: From $498
    21

    Mo

  • ORD–ONT, 09/22/26 – 09/29/26: From $297
    22

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  • ORD–ONT, 09/23/26 – 09/30/26: From $297
    23

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  • ORD–ONT, 09/24/26 – 10/01/26: From $297
    24

    Th

  • ORD–ONT, 09/25/26 – 10/02/26: From $297
    25

    Fr

  • ORD–ONT, 09/26/26 – 10/03/26: From $297
    26

    Sa

  • ORD–ONT, 09/27/26 – 10/04/26: From $297
    27

    Su

  • ORD–ONT, 09/28/26 – 10/05/26: From $427
    28

    Mo

  • ORD–ONT, 09/29/26 – 10/06/26: From $297
    29

    Tu

  • ORD–ONT, 09/30/26 – 10/07/26: From $297
    30

    We

  • ORD–ONT, 10/01/26 – 10/08/26: From $318
    01

    Th

    OCT

  • ORD–ONT, 10/02/26 – 10/09/26: From $339
    02

    Fr

  • ORD–ONT, 10/03/26 – 10/10/26: From $297
    03

    Sa

  • ORD–ONT, 10/04/26 – 10/11/26: From $318
    04

    Su

  • ORD–ONT, 10/05/26 – 10/12/26: From $318
    05

    Mo

  • ORD–ONT: cmp-view-offers-disclaimer. Find Offers
    06

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  • ORD–ONT: cmp-view-offers-disclaimer. Find Offers
    07

    We

    • range$297-$672

    DisclaimerFares displayed have been collected within the last 24hrs and may no longer be available at time of booking. Modifying this information may result in a different fare. To find the most updated fare, please visit aa.com. Fares listed may be Basic Economy, which class is subject to additional terms and conditions. Additional baggage fees and charges for optional products and services may apply.

    Find deals on Chicago to Ontario flights

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    Chicago (ORD)to

    Ontario (ONT)
    10/03/26 - 10/10/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    10/14/26 - 10/21/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    10/23/26 - 10/30/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    10/24/26 - 10/31/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    10/26/26 - 11/02/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    10/27/26 - 11/03/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    09/09/26 - 09/16/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    09/11/26 - 09/18/26

    Round trip

    Economy

    from
    $297Fare subject to changes
    Updated: 10 hours ago

    *Fares displayed have been collected within the last 24hrs and may no longer be available at time of booking. Some fares listed may include one or more connections that are Basic Economy, which class is subject to additional terms and conditions. Modifying this information may result in a different fare. To find the most updated fare, please visit aa.com. Additional baggage fees and charges for optional products and services may apply.

    Finding cheap flights from Chicago to Ontario

    Looking for lower fares on your trip from Chicago to Ontario? Here are a few ways to save.

    • Book early: Booking 1 to 3 months ahead can help you find lower fares
    • Be flexible with dates: Midweek travel, like Tuesdays and Wednesdays, can be more affordable
    • Travel during less busy periods: Flying outside peak travel times can help find lower fares and avoid crowds

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    • Extra legroom: More space with seats at the front of the Main Cabin or in exit rows.
    • Early boarding: Preferred Group 5 boarding allows easier access to overhead bins.
    • Complimentary drinks: Enjoy beer, wine and spirits on flights with full beverage service.

    Discover how Main Cabin Extra can enhance your trip.

    American Airlines flights from Chicago to Ontario