Flights from Ontario/LA, CA to Denver, CO

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

Sep 2026
from$214*
Last seen: 6 hours ago
One-way/Economy
Oct 2026
from$32*
Last seen: 23 hours ago
One-way/Economy
Nov 2026
from$32*
Last seen: 2 hours ago
One-way/Economy
cmp-daily-histogram-bars-legend-min-price-aria-label $32
cmp-daily-histogram-bars-legend-max-price-aria-label $220
Displaying fares for September-2026
  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    24

    Thu

    SEP

  • ONT–DEN: cmp-view-offers-disclaimer. Find Offers
    25

    Fri

  • ONT–DEN, Sep 26, 2026: from $214
    26

    Sat

  • ONT–DEN, Sep 27, 2026: from $220
    27

    Sun

  • ONT–DEN, Sep 28, 2026: from $214
    28

    Mon

  • ONT–DEN, Sep 29, 2026: from $214
    29

    Tue

  • ONT–DEN, Sep 30, 2026: from $214
    30

    Wed

  • ONT–DEN, Oct 1, 2026: from $214
    01

    Thu

    OCT

  • ONT–DEN, Oct 2, 2026: from $214
    02

    Fri

  • ONT–DEN, Oct 3, 2026: from $214
    03

    Sat

  • ONT–DEN, Oct 4, 2026: from $214
    04

    Sun

  • ONT–DEN, Oct 5, 2026: from $214
    05

    Mon

  • ONT–DEN, Oct 6, 2026: from $177
    06

    Tue

  • ONT–DEN, Oct 7, 2026: from $88
    07

    Wed

  • ONT–DEN, Oct 8, 2026: from $139
    08

    Thu

  • ONT–DEN, Oct 9, 2026: from $119
    09

    Fri

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

    Sat

  • ONT–DEN, Oct 11, 2026: from $160
    11

    Sun

  • ONT–DEN, Oct 12, 2026: from $119
    12

    Mon

  • ONT–DEN, Oct 13, 2026: from $88
    13

    Tue

  • ONT–DEN, Oct 14, 2026: from $43
    14

    Wed

  • ONT–DEN, Oct 15, 2026: from $60
    15

    Thu

  • ONT–DEN, Oct 16, 2026: from $81
    16

    Fri

  • ONT–DEN, Oct 17, 2026: from $83
    17

    Sat

  • ONT–DEN, Oct 18, 2026: from $176
    18

    Sun

  • ONT–DEN, Oct 19, 2026: from $83
    19

    Mon

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

    Tue

  • ONT–DEN, Oct 21, 2026: from $43
    21

    Wed

  • ONT–DEN, Oct 22, 2026: from $32
    22

    Thu

  • ONT–DEN, Oct 23, 2026: from $81
    23

    Fri

    • Range$32-$220

    *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 Dec 24, 2026

    From

    $78

    Last seen: 23 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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