Cheap flights from Ontario to San Diego from $70

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to San Diego departing on 9/24. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from Ontario to San Diego

Cheap round-trip flights

 Logo
10:28 pm - 6:42 pmONT-SAN
20h 14m1 stop
 Logo
7:47 pm - 8:26 amSAN-ONT
12h 39m1 stop
Mon, Sep 8 - Wed, Sep 10
Frontier Logo
8:00 am - 9:24 pmONT-SAN
13h 24m1 stop
Frontier Logo
8:00 am - 9:56 pmSAN-ONT
13h 56m1 stop
$158Frontier
Find Deal
Wed, Sep 24 - Wed, Oct 1
Frontier Logo
5:15 pm - 11:04 pmONT-SAN
5h 49m1 stop
Frontier Logo
4:06 pm - 7:47 amSAN-ONT
15h 41m1 stop
$192Frontier
Find Deal
Fri, Oct 24 - Sun, Oct 26
Frontier Logo
2:45 pm - 11:17 pmONT-SAN
8h 32m1 stop
Frontier Logo
8:00 am - 7:54 pmSAN-ONT
11h 54m2 stops
$202Frontier
Find Deal
Mon, Sep 8 - Wed, Sep 10
Frontier Logo
8:00 am - 9:24 pmONT-SAN
13h 24m1 stop
Frontier Logo
10:16 am - 9:56 pmSAN-ONT
11h 40m2 stops
$210Frontier
Find Deal
Wed, Sep 24 - Wed, Oct 1
United Airlines Logo
9:36 am - 10:44 pmONT-SAN
13h 08m1 stop
United Airlines Logo
7:28 pm - 12:13 pmSAN-ONT
16h 45m1 stop
$317United Airlines
Find Deal
Mon, Oct 20 - Tue, Oct 21
Alaska Airlines Logo
6:00 am - 2:48 pmONT-SAN
8h 48m1 stop
Alaska Airlines Logo
7:45 pm - 10:44 amSAN-ONT
14h 59m1 stop
$432Alaska Airlines
Find Deal
Wed, Sep 24 - Wed, Sep 24
American Airlines Logo
4:45 pm - 9:52 pmONT-SAN
5h 07m1 stop
American Airlines Logo
4:40 pm - 9:48 pmSAN-ONT
5h 08m1 stop
$729American Airlines
Find Deal
Thu, Sep 18 - Sun, Sep 21
American Airlines Logo
4:45 pm - 9:52 pmONT-SAN
5h 07m1 stop
American Airlines Logo
1:06 pm - 6:12 pmSAN-ONT
5h 06m1 stop
$730American Airlines
Find Deal
Thu, Sep 18 - Sun, Sep 21
Alaska Airlines Logo
7:10 am - 1:07 pmONT-SAN
5h 57m1 stop
Alaska Airlines Logo
7:15 am - 2:12 pmSAN-ONT
6h 57m1 stop
$757Alaska Airlines
Find Deal
Tue, Sep 9 - Tue, Sep 16

American Airlines flights from Ontario to San Diego

Our best American Airlines deals on Ontario to San Diego flight tickets
American Airlines
Sep 18
ONT4:45 pmOntario
5h 07m
1 stop
SAN9:52 pmSan Diego
Sep 21
SAN4:40 pmSan Diego
5h 08m
1 stop
ONT9:48 pmOntario
American Airlines
Sep 18
ONT4:45 pmOntario
5h 07m
1 stop
SAN9:52 pmSan Diego
Sep 21
SAN1:06 pmSan Diego
5h 06m
1 stop
ONT6:12 pmOntario
American Airlines
Sep 18
ONT4:45 pmOntario
5h 07m
1 stop
SAN9:52 pmSan Diego
Sep 21
SAN4:40 pmSan Diego
5h 08m
1 stop
ONT9:48 pmOntario

Frontier flights from Ontario to San Diego

Our best Frontier deals on Ontario to San Diego flight tickets
Frontier
Sep 24
ONT8:00 amOntario
13h 24m
1 stop
SAN9:24 pmSan Diego
Oct 1
SAN8:00 amSan Diego
13h 56m
1 stop
ONT9:56 pmOntario
Frontier
Oct 24
ONT5:15 pmOntario
5h 49m
1 stop
SAN11:04 pmSan Diego
Oct 26
SAN4:06 pmSan Diego
15h 41m
1 stop
ONT7:47 amOntario
Frontier
Sep 8
ONT2:45 pmOntario
8h 32m
1 stop
SAN11:17 pmSan Diego
Sep 10
SAN8:00 amSan Diego
11h 54m
2 stops
ONT7:54 pmOntario

momondo Fare Finder

 
Customize your flight search to find flights from Ontario to San Diego that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated August 28, 2025.
Use the filters below to find and compare flights from Ontario to San Diego that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Mon 9/8

10:28 pm-6:42 pm

1 stop20h 14m

San Diego

Wed 9/10

7:47 pm-8:26 am

1 stop12h 39m

$133

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Wed 9/24

8:00 am-9:24 pm

1 stop13h 24m

San Diego

Wed 10/1

8:00 am-9:56 pm

1 stop13h 56m

$158

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Fri 10/24

5:15 pm-11:04 pm

1 stop5h 49m

San Diego

Sun 10/26

4:06 pm-7:47 am

1 stop15h 41m

$192

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Mon 9/8

2:45 pm-11:17 pm

1 stop8h 32m

San Diego

Wed 9/10

8:00 am-7:54 pm

2 stops11h 54m

$202

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Wed 9/24

8:00 am-9:24 pm

1 stop13h 24m

San Diego

Wed 10/1

10:16 am-9:56 pm

2 stops11h 40m

$210

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Mon 10/20

9:36 am-10:44 pm

1 stop13h 08m

San Diego

Tue 10/21

7:28 pm-12:13 pm

1 stop16h 45m

$317

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Wed 9/24

6:00 am-2:48 pm

1 stop8h 48m

San Diego

Wed 9/24

7:45 pm-10:44 am

1 stop14h 59m

$432

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Thu 9/18

4:45 pm-9:52 pm

1 stop5h 07m

San Diego

Sun 9/21

4:40 pm-9:48 pm

1 stop5h 08m

$729

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Thu 9/18

4:45 pm-9:52 pm

1 stop5h 07m

San Diego

Sun 9/21

1:06 pm-6:12 pm

1 stop5h 06m

$730

OntarioSan Diego

ONT - SAN

ONTSAN

Ontario

Tue 9/9

7:10 am-1:07 pm

1 stop5h 57m

San Diego

Tue 9/16

7:15 am-2:12 pm

1 stop6h 57m

$757

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to San Diego from

How to get the cheapest flight ticket from Ontario to San Diego

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest day to depart on your flight to San Diego?

The cheapest day to depart from Ontario to San Diego is on a Tuesday. Travelers who choose to depart for San Diego on a Tuesday will often find tickets for as low as $179. If your travel schedule is flexible, try to avoid departing on a Monday because tickets tend to average around $407. These prices are subject to change though, so be sure to set up a Price Alert for flights to San Diego.

What is the cheapest time of day to depart on your flight to San Diego?

The cheapest time of day to fly to San Diego is at noon when flights can be purchased for as low as $179. Flights in the afternoon are often more expensive with an average ticket price of $261.

When to book flights from Ontario to San Diego

Are you open to changing your travel dates? Check out the ideal times to fly from Ontario to San Diego according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Ontario to San Diego (ONT to SAN) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to San Diego

Direct flights

None
There are no direct flights from Ontario to San Diego. There are no popular flight routes from Ontario to San Diego.
  • How far is Ontario to San Diego by plane?

    A flight from Ontario to San Diego will travel around 97.3 mi. By plane, this route typically takes 5h 07m.

  • When did momondo last update prices for flights from Ontario Airport to San Diego Airport?

    Prices for flights from Ontario Airport to San Diego Airport are updated daily.

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

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario Airport to San Diego Airport.

  • What documentation or ID do you need to fly to San Diego Airport?

    The necessary travel and health documents for your San Diego Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

Traveling to a place near San Diego?

Book flights to San Diego if you plan to visit one of these locations
Coronado
Chula Vista
El Cajon
Julian
La Mesa
National City
Imperial Beach
Poway
San Ysidro
Borrego Springs
Alpine
Lemon Grove
Santee

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to San Diego?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Ontario to San Diego. momondo saves you time and could save you money on your trip.

Can I find flights from Ontario to San Diego with flexible booking policies on momondo?

Yes. momondo allows you to filter the results for Ontario to San Diego flights to just show those with flexible booking policies.

How can momondo help me find flights from Ontario to San Diego?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to San Diego from Ontario.

I’m not ready to book a flight from Ontario to San Diego right now. Can momondo alert me if prices change?

Of course. momondo tracks the price of Ontario to San Diego flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

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1 adult
Tue 9/2
Tue 9/9

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