American Airlines flights from Chicago to Ontario

Recent searches for flights from Chicago to Ontario

Aug 2026
From$277*
Updated: 8 hours ago
Round tripIEconomy
Sep 2026
From$259*
Updated: 8 hours ago
Round tripIEconomy
Oct 2026
From$259*
Updated: 8 hours ago
Round tripIEconomy
cmp-daily-histogram-bars-legend-min-price-aria-label $259
cmp-daily-histogram-bars-legend-max-price-aria-label $608
Displaying fares for August-2026
  • ORD–ONT, 08/19/26 – 08/21/26: From $373
    19

    We

    AUG

  • ORD–ONT, 08/20/26 – 08/27/26: From $277
    20

    Th

  • ORD–ONT, 08/21/26 – 08/28/26: From $277
    21

    Fr

  • ORD–ONT, 08/22/26 – 08/29/26: From $277
    22

    Sa

  • ORD–ONT, 08/23/26 – 08/30/26: From $277
    23

    Su

  • ORD–ONT, 08/24/26 – 08/31/26: From $277
    24

    Mo

  • ORD–ONT, 08/25/26 – 09/01/26: From $277
    25

    Tu

  • ORD–ONT, 08/26/26 – 09/02/26: From $277
    26

    We

  • ORD–ONT, 08/27/26 – 09/03/26: From $377
    27

    Th

  • ORD–ONT, 08/28/26 – 09/04/26: From $277
    28

    Fr

  • ORD–ONT, 08/29/26 – 09/05/26: From $277
    29

    Sa

  • ORD–ONT, 08/30/26 – 09/06/26: From $277
    30

    Su

  • ORD–ONT, 08/31/26 – 09/07/26: From $417
    31

    Mo

  • ORD–ONT, 09/01/26 – 09/08/26: From $277
    01

    Tu

    SEP

  • ORD–ONT, 09/02/26 – 09/09/26: From $268
    02

    We

  • ORD–ONT, 09/03/26 – 09/10/26: From $268
    03

    Th

  • ORD–ONT, 09/04/26 – 09/11/26: From $298
    04

    Fr

  • ORD–ONT, 09/05/26 – 09/12/26: From $268
    05

    Sa

  • ORD–ONT, 09/06/26 – 09/13/26: From $329
    06

    Su

  • ORD–ONT, 09/07/26 – 09/14/26: From $608
    07

    Mo

  • ORD–ONT, 09/08/26 – 09/15/26: From $408
    08

    Tu

  • ORD–ONT, 09/09/26 – 09/16/26: From $259
    09

    We

  • ORD–ONT, 09/10/26 – 09/17/26: From $259
    10

    Th

  • ORD–ONT, 09/11/26 – 09/18/26: From $277
    11

    Fr

  • ORD–ONT, 09/12/26 – 09/19/26: From $259
    12

    Sa

  • ORD–ONT, 09/13/26 – 09/20/26: From $298
    13

    Su

  • ORD–ONT, 09/14/26 – 09/21/26: From $289
    14

    Mo

  • ORD–ONT, 09/15/26 – 09/22/26: From $259
    15

    Tu

  • ORD–ONT: cmp-view-offers-disclaimer. Find Offers
    16

    We

  • ORD–ONT: cmp-view-offers-disclaimer. Find Offers
    17

    Th

  • ORD–ONT: cmp-view-offers-disclaimer. Find Offers
    18

    Fr

    • range$259-$608

    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)
    10/14/26 - 10/21/26

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

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

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

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

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

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

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    09/24/26 - 10/01/26

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    09/26/26 - 10/03/26

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

    Ontario (ONT)
    09/29/26 - 10/06/26

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 hours ago

    Chicago (ORD)to

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

    Round trip

    Economy

    from
    $259Fare subject to changes
    Updated: 8 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

    Earn up to $500 back on your next American Airlines flight plus, 30,000 bonus miles. Offers vary elsewhere. Opens another site in a new window that may not meet accessibility guidelines.

    Upgrade your flight with Main Cabin Extra

    Make your trip more comfortable with Main Cabin Extra. Enjoy benefits like:

    • 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