Cheap flights from Ontario (ONT) from $23

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Fly to

Route

Depart

Return

Price

Cheapest one-way

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 9/30

11:45 am-3:07 pm

Nonstop2h 22m

$23

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Thu 9/10

11:45 am-3:07 pm

Nonstop2h 22m

$23

Quickest one-way

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Wed 11/18

6:00 am-7:30 am

Nonstop1h 30m

$59

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Sat 11/7

6:00 am-7:30 am

Nonstop1h 30m

$59

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Tue 11/17

3:50 pm-8:30 pm

1 stop4h 40m

$76

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Tue 9/8

3:35 pm-9:40 pm

1 stop6h 05m

$76

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Sat 10/17

4:29 pm-9:59 pm

1 stop4h 30m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 12/9

1:23 pm-7:22 pm

1 stop4h 59m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Sat 10/24

6:00 am-11:56 am

1 stop4h 56m

$99

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Tue 9/15

1:04 pm-7:40 pm

1 stop5h 36m

$99

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

Where can I directly fly to from Ontario?

Currently, 15 destinations can be reached directly via flights from Ontario.

Flights from Ontario to

Austin

from$118

Flights from Ontario to

Boise

from$138

Flights from Ontario to

Denver

from$104

Flights from Ontario to

Honolulu

from$162

Flights from Ontario to

Las Vegas

from$64

Flights from Ontario to

León, Guanajuato

from$99

Flights from Ontario to

Morelia

from$78

Flights from Ontario to

Oakland, California

from$88

Flights from Ontario to

Sacramento

from$105

Flights from Ontario to

San Francisco

from$41

Flights from Ontario to

San Jose, California

from$48

Flights from Ontario to

San José del Cabo

from$100

Flights from Ontario to

San Salvador

from$364

Flights from Ontario to

Santa Rosa

from$108

Flights from Ontario to

Seattle

from$59

Find the cheapest flights from Ontario

One-way

Last minute

International

Domestic

Cheap one-way flights from Ontario

Enter your travel dates to find the best prices.

11:45 am - 3:07 pmONT Ontario-DEN Denver Intl

2h 22mnonstop

$23Frontier

Wed, Sep 30

11:45 am - 3:07 pmONT Ontario-DEN Denver Intl

2h 22mnonstop

$23Frontier

Thu, Sep 10

6:00 am - 7:30 amONT Ontario-SFO San Francisco

1h 30mnonstop

$59United Airlines

Wed, Nov 18

6:00 am - 7:30 amONT Ontario-SFO San Francisco

1h 30mnonstop

$59United Airlines

Sat, Nov 7

3:50 pm - 8:30 pmONT Ontario-SFO San Francisco

4h 40m1 stop Phoenix Sky Harbor Intl

$76Southwest

Tue, Nov 17

3:35 pm - 9:40 pmONT Ontario-SFO San Francisco

6h 05m1 stop Phoenix Sky Harbor Intl

$76Southwest

Tue, Sep 8

4:29 pm - 9:59 pmONT Ontario-DEN Denver Intl

4h 30m1 stop Phoenix Sky Harbor Intl

$89American Airlines

Sat, Oct 17

1:23 pm - 7:22 pmONT Ontario-DEN Denver Intl

4h 59m1 stop Phoenix Sky Harbor Intl

$89American Airlines

Wed, Dec 9

6:00 am - 11:56 amONT Ontario-DEN Denver Intl

4h 56m1 stop Salt Lake City

$99Delta

Sat, Oct 24

1:04 pm - 7:40 pmONT Ontario-DEN Denver Intl

5h 36m1 stop Salt Lake City

$99Delta

Tue, Sep 15

Last-minute flight deals from Ontario

Enter your travel dates to find the best prices.

5:17 pm - 8:02 pmONT Ontario-SEA Seattle/Tacoma Intl

2h 45mnonstop

11:54 am - 2:45 pmSEA Seattle/Tacoma Intl-ONT Ontario

2h 51mnonstop

$165Frontier

Sun, Aug 23 - Wed, Aug 26

3:13 pm - 4:40 pmONT Ontario-SFO San Francisco

1h 27mnonstop

11:20 am - 3:49 pmSFO San Francisco-ONT Ontario

4h 29m1 stop Las Vegas Harry Reid Intl

$169Frontier

Wed, Aug 26 - Tue, Sep 1

7:13 pm - 7:16 amONT Ontario-ORD Chicago O'Hare Intl

10h 03m1 stop San Francisco

8:06 pm - 10:35 pmORD Chicago O'Hare Intl-ONT Ontario

4h 29mnonstop

$267United Airlines

Mon, Aug 24 - Fri, Aug 28

1:18 pm - 11:59 pmONT Ontario-ORD Chicago O'Hare Intl

8h 41m1 stop Denver Intl

8:06 pm - 10:35 pmORD Chicago O'Hare Intl-ONT Ontario

4h 29mnonstop

$267United Airlines

Wed, Aug 26 - Mon, Aug 31

1:06 pm - 9:33 pmONT Ontario-ORD Chicago O'Hare Intl

6h 27m1 stop Salt Lake City

1:51 pm - 8:05 pmORD Chicago O'Hare Intl-ONT Ontario

8h 14m1 stop Atlanta Hartsfield-Jackson

$268Delta

Sat, Aug 22 - Thu, Sep 10

1:06 pm - 9:33 pmONT Ontario-ORD Chicago O'Hare Intl

6h 27m1 stop Salt Lake City

5:30 am - 11:05 amORD Chicago O'Hare Intl-ONT Ontario

7h 35m1 stop Atlanta Hartsfield-Jackson

$268Delta

Sat, Aug 22 - Wed, Sep 9

12:59 pm - 10:00 pmONT Ontario-ORD Chicago O'Hare Intl

7h 01m1 stop Phoenix Sky Harbor Intl

12:10 pm - 6:58 pmORD Chicago O'Hare Intl-ONT Ontario

8h 48m1 stop Dallas/Fort Worth

$277American Airlines

Wed, Aug 26 - Sat, Aug 29

2:43 pm - 12:18 amONT Ontario-ORD Chicago O'Hare Intl

7h 35m1 stop Dallas/Fort Worth

5:00 am - 9:34 amORD Chicago O'Hare Intl-ONT Ontario

6h 34m1 stop Dallas/Fort Worth

$277American Airlines

Sat, Aug 22 - Thu, Aug 27

12:00 pm - 11:59 pmONT Ontario-ORD Chicago O'Hare Intl

9h 59m1 stop Seattle/Tacoma Intl

2:41 pm - 11:50 pmORD Chicago O'Hare Intl-ONT Ontario

11h 09m1 stop Denver Intl

$313Multiple Airlines

Wed, Aug 26 - Sat, Aug 29

7:59 pm - 6:20 amONT Ontario-ORD Chicago O'Hare Intl

8h 21m1 stop Seattle/Tacoma Intl

8:45 am - 7:01 pmORD Chicago O'Hare Intl-ONT Ontario

12h 16m1 stop Houston George Bush Intcntl

$313Multiple Airlines

Mon, Aug 24 - Wed, Aug 26

Cheapest international flights from Ontario

Enter your travel dates to find the best prices.

12:07 pm - 9:10 pmONT Ontario-YVR Vancouver Intl

9h 03m1 stop San Francisco

7:00 am - 7:40 pmYVR Vancouver Intl-ONT Ontario

12h 40m1 stop San Francisco

$244Multiple Airlines

Mon, Oct 5 - Mon, Oct 26

8:24 pm - 12:15 amONT Ontario-YVR Vancouver Intl

27h 51m2 stops Las Vegas Harry Reid Intl Calgary

7:00 am - 7:40 pmYVR Vancouver Intl-ONT Ontario

12h 40m1 stop San Francisco

$278Multiple Airlines

Mon, Oct 5 - Mon, Oct 26

11:45 am - 4:50 pmONT Ontario-YVR Vancouver Intl

29h 05m2 stops Denver Intl Calgary

3:30 pm - 7:40 pmYVR Vancouver Intl-ONT Ontario

28h 10m1 stop San Francisco

$288Multiple Airlines

Wed, Sep 30 - Wed, Oct 7

1:38 pm - 11:40 pmONT Ontario-YVR Vancouver Intl

10h 02m1 stop Las Vegas Harry Reid Intl

10:40 am - 9:09 amYVR Vancouver Intl-ONT Ontario

22h 29m2 stops Calgary Las Vegas Harry Reid Intl

$295Multiple Airlines

Thu, Oct 8 - Tue, Oct 13

11:45 am - 4:50 pmONT Ontario-YVR Vancouver Intl

29h 05m2 stops Denver Intl Calgary

9:40 am - 4:59 pmYVR Vancouver Intl-ONT Ontario

7h 19m1 stop Las Vegas Harry Reid Intl

$299Multiple Airlines

Wed, Sep 9 - Fri, Sep 11

2:30 pm - 4:15 pmONT Ontario-YVR Vancouver Intl

25h 45m1 stop Las Vegas Harry Reid Intl

3:30 pm - 7:40 pmYVR Vancouver Intl-ONT Ontario

28h 10m1 stop San Francisco

$303Multiple Airlines

Wed, Sep 30 - Wed, Oct 7

8:24 pm - 4:15 pmONT Ontario-YVR Vancouver Intl

19h 51m1 stop Las Vegas Harry Reid Intl

6:45 am - 9:09 amYVR Vancouver Intl-ONT Ontario

26h 24m2 stops Calgary Las Vegas Harry Reid Intl

$305Multiple Airlines

Mon, Sep 14 - Mon, Sep 21

2:30 pm - 4:15 pmONT Ontario-YVR Vancouver Intl

25h 45m1 stop Las Vegas Harry Reid Intl

8:20 am - 11:47 pmYVR Vancouver Intl-ONT Ontario

15h 27m2 stops Los Angeles Denver Intl

$309Multiple Airlines

Wed, Sep 9 - Sat, Sep 12

8:00 am - 8:30 pmONT Ontario-YVR Vancouver Intl

12h 30m1 stop Las Vegas Harry Reid Intl

5:00 am - 10:30 amYVR Vancouver Intl-ONT Ontario

29h 30m2 stops Calgary Denver Intl

$310Multiple Airlines

Thu, Sep 10 - Mon, Sep 14

8:00 am - 4:15 pmONT Ontario-YVR Vancouver Intl

8h 15m1 stop Las Vegas Harry Reid Intl

5:00 am - 10:30 amYVR Vancouver Intl-ONT Ontario

29h 30m2 stops Calgary Denver Intl

$312Multiple Airlines

Thu, Sep 10 - Fri, Sep 11

Flights from Ontario - Travel Insights & Trends

Get data-powered insights and trends into flights from Ontario to help you craft the best travel plan.

Prices

Other information

What are the most popular domestic flights out of Ontario?

According to searches, the most popular destinations for domestic flights from Ontario among momondo users are San Jose, California, Phoenix, Denver, Chicago and Honolulu.

What are the cheapest cities to fly to from Ontario?

The cheapest city to fly to from Ontario currently is San Francisco at $41. The next cheapest destinations are San Jose, Seattle, Las Vegas, Houston and Phoenix.

Frequently asked questions regarding flights from Ontario

Which airlines are currently offering the cheapest flights from Ontario?

Our data suggests that currently, the cheapest flights from Ontario are being offered by Frontier, Alaska Airlines, and JetBlue. For example, Frontier flights from Ontario to San Jose, California, start at $29, Alaska Airlines flights from Ontario to San Francisco cost around $51, and JetBlue flights from Ontario to Las Vegas are around $56.

What is the cheapest flight available from Ontario?

Currently, the cheapest flight from Ontario found by our users is for $41 to San Francisco. Prices will vary according to several factors such as the departure date and time, but on average you can expect to pay around $1,917 to travel from Ontario to San Francisco.

Which destinations have the most frequent flights from Ontario?

Dallas/Fort Worth Airport, Seattle and Atlanta are currently the destinations served most frequently from Ontario, with 19, 13 and 12 flights per day on average, respectively.

Which airlines can you fly with from Ontario?

Airlines including American Airlines, Delta and United Airlines frequently fly from Ontario. You can view other airlines by performing a quick search in the form above.

What is the cheapest first class flight from Ontario?

If you are looking for a cheap first class flight, consider flights to San Francisco, for which the starting price of a first class seat can be as low as $337.

When did momondo last update prices for flights from Ontario Airport?

Prices for flights from Ontario Airport refresh daily.

How many operators does momondo search for flights from Ontario Airport?

As of August 2026, there are 28 operators available to choose from for flights from Ontario Airport.

How old do you have to be to fly from Ontario Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Ontario Airport.

What documentation or ID do you need to fly to Ontario Airport?

The required travel and health documents for your Ontario Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.