Cheap flights from Ontario (ONT) from $33

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Fly to

Route

Depart

Return

Price

Cheapest one-way

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Tue 10/27

6:25 am-9:46 am

Nonstop2h 21m

$33

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 10/21

6:15 am-9:41 am

Nonstop2h 26m

$33

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Tue 12/29

6:00 am-7:33 am

Nonstop1h 33m

$59

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

Thu 11/5

6:50 pm-12:10 am

1 stop5h 20m

$76

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Mon 11/2

6:50 pm-12:05 am

1 stop5h 15m

$76

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Sat 10/31

1:05 pm-6:13 pm

1 stop4h 08m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 2/3

4:19 pm-9:48 pm

1 stop4h 29m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Tue 10/27

6:00 am-11:56 am

1 stop4h 56m

$99

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Sat 10/24

1:35 pm-7:34 pm

1 stop4h 59m

$99

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

Where can I directly fly to from Ontario?

Currently, 16 destinations can be reached directly via flights from Ontario.

Flights from Ontario to

Boise

from$197

Flights from Ontario to

Denver

from$116

Flights from Ontario to

Guadalajara

from$120

Flights from Ontario to

Honolulu

from$162

Flights from Ontario to

Las Vegas

from$63

Flights from Ontario to

León, Guanajuato

from$106

Flights from Ontario to

Morelia

from$102

Flights from Ontario to

Oakland, California

from$118

Flights from Ontario to

Portland

from$159

Flights from Ontario to

Sacramento

from$99

Flights from Ontario to

San Francisco

from$31

Flights from Ontario to

San Jose, California

from$58

Flights from Ontario to

San José del Cabo

from$100

Flights from Ontario to

San Salvador

from$407

Flights from Ontario to

Santa Rosa

from$108

Flights from Ontario to

Seattle

from$50

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.

6:25 am - 9:46 amONT Ontario-DEN Denver Intl

2h 21mnonstop

$33Frontier

Tue, Oct 27

6:15 am - 9:41 amONT Ontario-DEN Denver Intl

2h 26mnonstop

$33Frontier

Wed, Oct 21

6:00 am - 7:33 amONT Ontario-SFO San Francisco

1h 33mnonstop

$59United Airlines

Tue, Dec 29

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

1h 30mnonstop

$59United Airlines

Wed, Nov 18

6:50 pm - 12:10 amONT Ontario-SFO San Francisco

5h 20m1 stop Las Vegas Harry Reid Intl

$76Southwest

Thu, Nov 5

6:50 pm - 12:05 amONT Ontario-SFO San Francisco

5h 15m1 stop Las Vegas Harry Reid Intl

$76Southwest

Mon, Nov 2

1:05 pm - 6:13 pmONT Ontario-DEN Denver Intl

4h 08m1 stop Phoenix Sky Harbor Intl

$89American Airlines

Sat, Oct 31

4:19 pm - 9:48 pmONT Ontario-DEN Denver Intl

4h 29m1 stop Phoenix Sky Harbor Intl

$89American Airlines

Wed, Feb 3

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

4h 56m1 stop Salt Lake City

$99Delta

Tue, Oct 27

1:35 pm - 7:34 pmONT Ontario-DEN Denver Intl

4h 59m1 stop Salt Lake City

$99Delta

Sat, Oct 24

Last-minute flight deals from Ontario

Enter your travel dates to find the best prices.

12:07 pm - 1:43 pmONT Ontario-SFO San Francisco

1h 36mnonstop

6:02 pm - 7:40 pmSFO San Francisco-ONT Ontario

1h 38mnonstop

$118Frontier

Mon, Oct 5 - Sun, Oct 11

12:07 pm - 1:43 pmONT Ontario-SFO San Francisco

1h 36mnonstop

6:02 pm - 7:40 pmSFO San Francisco-ONT Ontario

1h 38mnonstop

$157Frontier

Fri, Oct 2 - Sun, Oct 11

5:00 pm - 10:50 pmONT Ontario-SFO San Francisco

5h 50m1 stop Phoenix Sky Harbor Intl

7:00 am - 11:55 amSFO San Francisco-ONT Ontario

4h 55m1 stop Las Vegas Harry Reid Intl

$245Southwest

Tue, Oct 6 - Wed, Nov 4

4:15 pm - 9:40 pmONT Ontario-SFO San Francisco

5h 25m1 stop Las Vegas Harry Reid Intl

7:00 am - 4:10 pmSFO San Francisco-ONT Ontario

9h 10m2 stops Las Vegas Harry Reid Intl Phoenix Sky Harbor Intl

$250Southwest

Tue, Oct 6 - Wed, Nov 4

1:52 pm - 3:21 pmONT Ontario-SFO San Francisco

1h 29mnonstop

9:25 pm - 10:51 pmSFO San Francisco-ONT Ontario

1h 26mnonstop

$279United Airlines

Sat, Oct 3 - Sat, Oct 10

1:52 pm - 3:21 pmONT Ontario-SFO San Francisco

1h 29mnonstop

8:40 am - 10:23 amSFO San Francisco-ONT Ontario

1h 43mnonstop

$279United Airlines

Tue, Oct 6 - Tue, Oct 13

6:00 am - 6:01 pmONT Ontario-ORD Chicago O'Hare Intl

10h 01m1 stop Seattle/Tacoma Intl

6:20 am - 5:12 pmORD Chicago O'Hare Intl-ONT Ontario

12h 52m2 stops Minneapolis St Paul Seattle/Tacoma Intl

$313Delta

Fri, Oct 2 - Tue, Oct 20

4:29 pm - 12:35 amONT Ontario-ORD Chicago O'Hare Intl

6h 06m1 stop Phoenix Sky Harbor Intl

7:00 pm - 10:53 pmORD Chicago O'Hare Intl-ONT Ontario

5h 53m1 stop Phoenix Sky Harbor Intl

$317American Airlines

Wed, Oct 7 - Fri, Oct 9

1:05 pm - 11:30 pmONT Ontario-ORD Chicago O'Hare Intl

8h 25m1 stop Phoenix Sky Harbor Intl

5:10 pm - 10:53 pmORD Chicago O'Hare Intl-ONT Ontario

7h 43m1 stop Phoenix Sky Harbor Intl

$317American Airlines

Wed, Oct 7 - Fri, Oct 9

6:20 am - 4:53 pmONT Ontario-ORD Chicago O'Hare Intl

8h 33m1 stop Seattle/Tacoma Intl

1:26 pm - 10:43 pmORD Chicago O'Hare Intl-ONT Ontario

11h 17m2 stops Detroit Metropolitan Wayne County Seattle/Tacoma Intl

$322Delta

Wed, Oct 7 - Fri, Oct 9

Cheapest international flights from Ontario

Enter your travel dates to find the best prices.

10:20 am - 12:35 pmLAX Los Angeles-MAD Madrid Barajas

17h 15m1 stop Casablanca Mohamed V

8:10 pm - 8:20 amMAD Madrid Barajas-LAX Los Angeles

21h 10m1 stop Casablanca Mohamed V

$575Royal Air Maroc

Tue, Oct 6 - Thu, Oct 15

8:30 am - 8:00 amLAX Los Angeles-MAD Madrid Barajas

14h 30m1 stop Montreal Pierre Elliott Trudeau Intl

6:05 am - 10:31 pmMAD Madrid Barajas-LAX Los Angeles

25h 26m2 stops Frankfurt am Main Vancouver Intl

$576Air Canada

Wed, Nov 25 - Wed, Dec 9

6:25 pm - 6:35 pmLAX Los Angeles-MAD Madrid Barajas

15h 10m1 stop London Heathrow

12:55 pm - 4:40 pmMAD Madrid Barajas-LAX Los Angeles

12h 45mnonstop

$577Iberia

Wed, Dec 2 - Wed, Dec 9

9:20 am - 10:35 pmLAX Los Angeles-BVA Paris Beauvais-Tille

28h 15m2 stops Casablanca Mohamed V Barcelona-El Prat

2:05 pm - 7:20 amBVA Paris Beauvais-Tille-LAX Los Angeles

26h 15m2 stops Barcelona-El Prat Casablanca Mohamed V

$673Multiple Airlines

Fri, Nov 13 - Thu, Nov 26

9:20 am - 10:35 pmLAX Los Angeles-BVA Paris Beauvais-Tille

28h 15m2 stops Casablanca Mohamed V Barcelona-El Prat

8:25 am - 7:20 amBVA Paris Beauvais-Tille-LAX Los Angeles

31h 55m2 stops Barcelona-El Prat Casablanca Mohamed V

$682Multiple Airlines

Fri, Nov 6 - Mon, Nov 16

7:00 am - 2:40 pmLGB Long Beach Municipal-CPH Kastrup Copenhagen

22h 40m2 stops Salt Lake City Paris Charles de Gaulle

6:45 am - 6:37 pmCPH Kastrup Copenhagen-LGB Long Beach Municipal

20h 52m2 stops Paris Charles de Gaulle Salt Lake City

$685Delta

Wed, Nov 11 - Thu, Nov 26

9:40 am - 2:40 pmBUR Hollywood Burbank-CPH Kastrup Copenhagen

20h 00m2 stops Salt Lake City Paris Charles de Gaulle

12:05 pm - 4:13 pmCPH Kastrup Copenhagen-BUR Hollywood Burbank

37h 08m2 stops Amsterdam Schiphol Salt Lake City

$685Delta

Wed, Nov 11 - Wed, Nov 25

7:00 am - 5:00 pmONT Ontario-CPH Kastrup Copenhagen

25h 00m2 stops Seattle/Tacoma Intl Paris Charles de Gaulle

9:55 am - 8:54 pmCPH Kastrup Copenhagen-ONT Ontario

19h 59m2 stops Amsterdam Schiphol Atlanta Hartsfield-Jackson

$685Delta

Mon, Nov 9 - Wed, Nov 25

9:55 pm - 1:20 amLAX Los Angeles-BKK Bangkok Suvarnabhumi

37h 25m1 stop Shenzhen

2:20 am - 6:35 pmBKK Bangkok Suvarnabhumi-LAX Los Angeles

31h 15m1 stop Shenzhen

$687Multiple Airlines

Tue, Oct 27 - Mon, Nov 2

11:30 am - 9:50 amLAX Los Angeles-BKK Bangkok Suvarnabhumi

31h 20m2 stops Shanghai Pu Dong Kunming Changshui

10:50 am - 9:05 amBKK Bangkok Suvarnabhumi-LAX Los Angeles

37h 15m3 stops Kunming Changshui Fuzhou Shanghai Pu Dong

$688China Eastern

Fri, Nov 13 - Sun, Nov 22

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 Chicago, Chicago, Phoenix, Denver 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 $31. The next cheapest destinations are Seattle, San Jose, Phoenix, Las Vegas and San José del Cabo.

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 $49, and JetBlue flights from Ontario to Las Vegas are around $57.

What is the cheapest flight available from Ontario?

Currently, the cheapest flight from Ontario found by our users is for $31 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 $915 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 15, 13 and 9 flights per day on average, respectively.

Which airlines can you fly with from Ontario?

Airlines including American Airlines, United Airlines and Delta 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 $354.

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 October 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.