Cheap flights from Ontario (ONT) from $33

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Route

Depart

Return

Price

Cheapest one-way

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Thu 11/12

11:52 am-3:13 pm

Nonstop2h 21m

$33

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Tue 11/10

11:52 am-3:13 pm

Nonstop2h 21m

$33

Quickest one-way

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Sat 10/3

8:03 am-9:30 am

Nonstop1h 27m

$59

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Tue 11/10

1:35 pm-3:05 pm

Nonstop1h 30m

$59

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Sat 9/26

2:55 pm-6:25 pm

1 stop3h 30m

$76

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Mon 11/9

5:20 pm-11:40 pm

1 stop6h 20m

$76

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Tue 2/2

11:36 am-6:56 pm

1 stop6h 20m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Mon 1/11

7:10 am-2:07 pm

1 stop5h 57m

$89

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 3/3

6:00 am-11:55 am

1 stop4h 55m

$99

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Wed 9/30

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

Boise

from$138

Flights from Ontario to

Denver

from$107

Flights from Ontario to

Guadalajara

from$142

Flights from Ontario to

Honolulu

from$162

Flights from Ontario to

Las Vegas

from$60

Flights from Ontario to

León, Guanajuato

from$101

Flights from Ontario to

Morelia

from$78

Flights from Ontario to

Oakland, California

from$109

Flights from Ontario to

Sacramento

from$89

Flights from Ontario to

San Francisco

from$41

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$367

Flights from Ontario to

Santa Rosa

from$108

Flights from Ontario to

Seattle

from$49

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.

11:52 am - 3:13 pmONT Ontario-DEN Denver Intl

2h 21mnonstop

$33Frontier

Thu, Nov 12

11:52 am - 3:13 pmONT Ontario-DEN Denver Intl

2h 21mnonstop

$33Frontier

Tue, Nov 10

8:03 am - 9:30 amONT Ontario-SFO San Francisco

1h 27mnonstop

$59United Airlines

Sat, Oct 3

1:35 pm - 3:05 pmONT Ontario-SFO San Francisco

1h 30mnonstop

$59United Airlines

Tue, Nov 10

2:55 pm - 6:25 pmONT Ontario-SFO San Francisco

3h 30m1 stop Las Vegas Harry Reid Intl

$76Southwest

Sat, Sep 26

5:20 pm - 11:40 pmONT Ontario-SFO San Francisco

6h 20m1 stop Phoenix Sky Harbor Intl

$76Southwest

Mon, Nov 9

11:36 am - 6:56 pmONT Ontario-DEN Denver Intl

6h 20m1 stop Seattle/Tacoma Intl

$89Alaska Airlines

Tue, Feb 2

7:10 am - 2:07 pmONT Ontario-DEN Denver Intl

5h 57m1 stop Portland

$89Alaska Airlines

Mon, Jan 11

6:00 am - 11:55 amONT Ontario-DEN Denver Intl

4h 55m1 stop Salt Lake City

$99Delta

Wed, Mar 3

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

5h 36m1 stop Salt Lake City

$99Delta

Wed, Sep 30

Last-minute flight deals from Ontario

Enter your travel dates to find the best prices.

8:48 am - 10:15 amONT Ontario-SFO San Francisco

1h 27mnonstop

6:02 pm - 7:36 pmSFO San Francisco-ONT Ontario

1h 34mnonstop

$68Frontier

Sun, Sep 6 - Thu, Sep 10

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

1h 36mnonstop

6:02 pm - 7:36 pmSFO San Francisco-ONT Ontario

1h 34mnonstop

$68Frontier

Thu, Sep 10 - Thu, Sep 10

6:08 am - 7:35 amONT Ontario-SFO San Francisco

1h 27mnonstop

9:25 pm - 10:59 pmSFO San Francisco-ONT Ontario

1h 34mnonstop

$252United Airlines

Tue, Sep 8 - Wed, Sep 30

6:08 am - 7:35 amONT Ontario-SFO San Francisco

1h 27mnonstop

4:40 pm - 6:11 pmSFO San Francisco-ONT Ontario

1h 31mnonstop

$257United Airlines

Thu, Sep 10 - Sat, Sep 19

5:44 pm - 8:40 pmONT Ontario-SEA Seattle/Tacoma Intl

2h 56mnonstop

8:20 am - 2:58 pmSEA Seattle/Tacoma Intl-ONT Ontario

6h 38m1 stop Portland

$257Multiple Airlines

Wed, Sep 9 - Thu, May 20

5:44 pm - 8:40 pmONT Ontario-SEA Seattle/Tacoma Intl

2h 56mnonstop

1:30 pm - 8:24 pmSEA Seattle/Tacoma Intl-ONT Ontario

6h 54m1 stop Portland

$263Multiple Airlines

Thu, Sep 10 - Sun, Sep 13

1:10 pm - 6:20 pmONT Ontario-SFO San Francisco

5h 10m1 stop Phoenix Sky Harbor Intl

11:05 am - 3:15 pmSFO San Francisco-ONT Ontario

4h 10m1 stop Las Vegas Harry Reid Intl

$277Southwest

Tue, Sep 8 - Thu, Sep 10

5:50 am - 11:35 amONT Ontario-SFO San Francisco

5h 45m1 stop Las Vegas Harry Reid Intl

6:50 am - 12:40 pmSFO San Francisco-ONT Ontario

5h 50m1 stop Las Vegas Harry Reid Intl

$277Southwest

Sat, Sep 5 - Wed, Sep 9

10:00 am - 4:02 pmONT Ontario-SFO San Francisco

6h 02m1 stop Phoenix Sky Harbor Intl

12:23 pm - 6:15 pmSFO San Francisco-ONT Ontario

5h 52m1 stop Phoenix Sky Harbor Intl

$277American Airlines

Sun, Sep 6 - Tue, Sep 8

10:00 am - 4:02 pmONT Ontario-SFO San Francisco

6h 02m1 stop Phoenix Sky Harbor Intl

5:50 am - 12:06 pmSFO San Francisco-ONT Ontario

6h 16m1 stop Phoenix Sky Harbor Intl

$277American Airlines

Sun, Sep 6 - Wed, Sep 9

Cheapest international flights from Ontario

Enter your travel dates to find the best prices.

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$288Volaris

Sun, Oct 4 - Tue, Oct 13

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$290Volaris

Sat, Oct 3 - Fri, Oct 9

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$292Volaris

Mon, Oct 5 - Tue, Oct 27

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$293Volaris

Tue, Oct 13 - Tue, Oct 20

12:55 am - 4:58 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

5:40 pm - 7:46 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$294Volaris

Tue, Oct 13 - Fri, Oct 23

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$295Volaris

Fri, Oct 23 - Tue, Oct 27

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$296Volaris

Tue, Oct 6 - Tue, Oct 13

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$297Volaris

Mon, Oct 5 - Mon, Oct 12

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

5:40 pm - 7:46 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$298Volaris

Fri, Oct 16 - Fri, Oct 23

9:36 pm - 1:39 amONT Ontario-GDL Guadalajara Miguel Hidal

3h 03mnonstop

8:59 pm - 11:05 pmGDL Guadalajara Miguel Hidal-ONT Ontario

3h 06mnonstop

$299Volaris

Sat, Oct 17 - Wed, Oct 28

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, Phoenix, Portland, Chicago and Denver.

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 Seattle, San Jose, 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 $50, 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 $1,545 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 20, 11 and 10 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 $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 September 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.