Flights from Ontario/LA, CA to Denver, CO

Promo Code

Best Deals on Flights From Ontario/LA, CA (ONT) to Denver, CO (DEN)

Aug 2026
from$49*
Last seen: 22 hours ago
One-way/Economy
Sep 2026
from$24*
Last seen: 2 hours ago
One-way/Economy
Oct 2026
from$24*
Last seen: 19 hours ago
One-way/Economy
cmp-daily-histogram-bars-legend-min-price-aria-label $32
cmp-daily-histogram-bars-legend-max-price-aria-label $179
Displaying fares for August-2026
  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    09

    Sun

    AUG

  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    10

    Mon

  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    11

    Tue

  • ONT–DEN, Aug 12, 2026: from $179
    12

    Wed

  • ONT–DEN, Aug 13, 2026: from $179
    13

    Thu

  • ONT–DEN, Aug 14, 2026: from $179
    14

    Fri

  • ONT–DEN, Aug 15, 2026: from $179
    15

    Sat

  • ONT–DEN, Aug 16, 2026: from $169
    16

    Sun

  • ONT–DEN, Aug 17, 2026: from $169
    17

    Mon

  • ONT–DEN, Aug 18, 2026: from $169
    18

    Tue

  • ONT–DEN, Aug 19, 2026: from $169
    19

    Wed

  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    20

    Thu

  • ONT–DEN, Aug 21, 2026: from $169
    21

    Fri

  • ONT–DEN, Aug 22, 2026: from $129
    22

    Sat

  • ONT–DEN, Aug 23, 2026: from $129
    23

    Sun

  • ONT–DEN, Aug 24, 2026: from $129
    24

    Mon

  • ONT–DEN, Aug 25, 2026: from $129
    25

    Tue

  • ONT–DEN, Aug 26, 2026: from $129
    26

    Wed

  • ONT–DEN, Aug 27, 2026: from $129
    27

    Thu

  • ONT–DEN, Aug 28, 2026: from $129
    28

    Fri

  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    29

    Sat

  • ONT–DEN, Aug 30, 2026: from $129
    30

    Sun

  • ONT–DEN, Aug 31, 2026: from $49
    31

    Mon

  • ONT–DEN, Sep 1, 2026: from $54
    01

    Tue

    SEP

  • ONT–DEN, Sep 2, 2026: from $77
    02

    Wed

  • ONT–DEN, Sep 3, 2026: from $128
    03

    Thu

  • ONT–DEN, Sep 4, 2026: from $129
    04

    Fri

  • ONT–DEN, Sep 5, 2026: from $32
    05

    Sat

  • ONT–DEN, Sep 6, 2026: from $32
    06

    Sun

  • ONT–DEN, Sep 7, 2026: from $100
    07

    Mon

  • ONT–DEN, Sep 8, 2026: from $128
    08

    Tue

    • Range$32-$179

    *Prices found by others in the previous 48 hours for round-trip flights. Prices shown may also require membership in our travel club, Discount Den.

    Flights Deals from Ontario/LA, CA to Denver, CO on Frontier

    $
    Flights Deals from Ontario/LA, CA to Denver, CO on Frontier
    From
    To
    Ontario/LA, CA (ONT)Denver, CO (DEN)One-way
    /
    Discount Den Basic Fare    		Departing Nov 18, 2026

    From

    $83

    Last seen: 4 hours ago

    *Prices found by others in the previous 48 hours for one-way flights. Prices shown may also require membership in our travel club, Discount Den®.

    Ontario/LA, CA Denver, CO

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