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$138+ Cheap flights from San Juan to Ontario (ONT)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/1. Fares are subject to change and may not be available on all flights or dates of travel.
SJU — ONT
Jun 9 — Jun 161
Tue 6/9
Tue 6/16
1 adult, Economy
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Cheap flight deals from San Juan to Ontario

Cheapest flights from San Juan to Ontario
Explore the most affordable flight options available from San Juan to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 10, 2026.

This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/172:26 pm
SJU
-
ONT
1 stop10h 30m
Delta
Fri 9/2510:59 pm
ONT
-
SJU
1 stop9h 49m
Delta
Deal found 5/6$374
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/127:30 am
SJU
-
ONT
1 stop13h 31m
Delta
Fri 9/2510:59 pm
ONT
-
SJU
1 stop9h 49m
Delta
Deal found 5/6$427
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/1412:56 pm
SJU
-
ONT
2 stops13h 52m
Delta
Tue 7/285:10 pm
ONT
-
SJU
2 stops17h 01m
Delta
Deal found 5/6$430
This United Airlines deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/162:20 pm
SJU
-
ONT
1 stop10h 39m
United Airlines
Tue 9/225:45 am
ONT
-
SJU
2 stops15h 05m
United Airlines
Deal found 5/6$464
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1412:58 pm
SJU
-
ONT
1 stop11h 58m
Delta
Fri 9/2510:59 pm
ONT
-
SJU
1 stop11h 17m
Delta
Deal found 5/6$472
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/127:30 am
SJU
-
ONT
1 stop13h 31m
Delta
Mon 9/2110:59 pm
ONT
-
SJU
1 stop11h 17m
Delta
Deal found 5/6$480
This American Airlines deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/127:05 pm
SJU
-
ONT
2 stops27h 50m
American Airlines
Tue 9/2211:59 pm
ONT
-
SJU
2 stops11h 46m
American Airlines
Deal found 5/6$486
This American Airlines deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/126:30 am
SJU
-
ONT
2 stops19h 36m
American Airlines
Wed 9/2311:59 pm
ONT
-
SJU
2 stops21h 00m
American Airlines
Deal found 5/6$491
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/1312:58 pm
SJU
-
ONT
1 stop11h 58m
Delta
Wed 9/2310:59 pm
ONT
-
SJU
1 stop11h 17m
Delta
Deal found 5/6$520
This Faresmojo deal was found by Cheapflights users on 5/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Faresmojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/171:14 pm
SJU
-
ONT
1 stop11h 34m
JetBlue
Sat 5/307:05 am
ONT
-
SJU
1 stop10h 25m
JetBlue
Deal found 5/5$524
This Delta deal was found by Cheapflights users on 5/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1412:58 pm
SJU
-
ONT
1 stop11h 58m
Delta
Mon 9/2110:59 pm
ONT
-
SJU
1 stop11h 17m
Delta
Deal found 5/6$525

Find flight deals from San Juan to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from San Juan (PR1) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated May 10, 2026.

Round-trip from

$374
(Delta)

One-way from

$138
(Frontier)

Popular in

March

Cheapest in

January

Average price

$428
From San Juan to Ontario
Search Deals
One-way flight from San Juan to Ontario
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($14 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from San Juan to Ontario 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, Cheapflights users made 2,558,603 searches. Data last updated May 10, 2026.
Use the filters below to find and compare flights from San Juan to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Tue 7/7

2:05 am-9:55 pm

1 stop22h 50m

Ontario

Sat 8/8

1:18 pm-5:29 am

2 stops13h 11m

$667
Quickest round-trip

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Thu 7/23

1:40 pm-8:42 pm

1 stop10h 02m

Ontario

Fri 7/31

5:00 am-5:38 pm

1 stop9h 38m

$677

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Sun 5/24

5:45 am-3:00 pm

1 stop12h 15m

Ontario

Sun 5/24

9:55 pm-12:10 pm

1 stop11h 15m

$716

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Sat 5/23

2:48 pm-9:48 pm

1 stop10h 00m

Ontario

Wed 5/27

10:00 pm-12:01 pm

1 stop11h 01m

$723

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Sat 5/23

2:48 pm-9:48 pm

1 stop10h 00m

Ontario

Sat 5/30

7:05 am-10:17 pm

1 stop12h 12m

$723

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Tue 6/2

9:54 am-8:47 pm

1 stop13h 53m

Ontario

Mon 6/8

10:41 pm-1:16 pm

1 stop11h 35m

$832

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Tue 6/2

2:05 am-9:55 pm

1 stop22h 50m

Ontario

Thu 6/4

5:45 am-8:38 pm

1 stop11h 53m

$857

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Tue 6/2

2:05 am-9:55 pm

1 stop22h 50m

Ontario

Tue 6/9

5:45 am-8:38 pm

1 stop11h 53m

$857

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Sun 7/5

2:05 am-9:55 pm

1 stop22h 50m

Ontario

Fri 7/17

1:50 pm-8:34 pm

2 stops27h 44m

$864

San JuanOntario

SJU - ONT

SJUONT

San Juan Luis Munoz Marin Intl

Fri 5/22

2:05 am-8:42 pm

2 stops21h 37m

Ontario

Wed 5/27

5:00 am-5:38 pm

1 stop9h 38m

$890

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/6

Showing 1-10 of 21 resultsSorted by cheapest first
1
2
3

Best time to book a flight from San Juan to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from San Juan with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from San Juan to Ontario

How far ahead should I book a flight from San Juan to Ontario?

The best time to book flights from San Juan to Ontario is 86 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from San Juan to Ontario?

Currently, May is the cheapest month in which you can book a flight from San Juan to Ontario (average of $283). Flying from San Juan to Ontario in March is currently the most expensive (average of $556). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

How much does it cost to fly round-trip from San Juan to Ontario?

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated May 10, 2026.
Read through reviews of airlines operating flights from San Juan to Ontario, such as United Airlines and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,694 reviews

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.
United Airlines
7.4
Good
9,694 reviews
United Airlines
7.4
Good
9,694 reviews

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.
American Airlines
7.1
Good
11,667 reviews
United Airlines
7.4
Good
9,694 reviews

Boarding

7.7

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.

Related info for your journey

Find useful and relevant information for your journey from San Juan to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ontario from San Juan?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly into when you book flights from San Juan to Ontario. 2 airlines have flights to Ontario from San Juan on a regular basis. Booking flights from San Juan to Ontario should not be difficult; the airport handles an average of 0 inbound flights from San Juan per day.

  • How long is the flight from San Juan to Ontario?

    A quick flight from San Juan to Ontario can take about 10h. United Airlines provides one of the quickest options available for as low as $723. The distance from San Juan to Ontario is about 3334 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from San Juan to Ontario round-trip?

    Flying on American Airlines is currently your cheapest option to Ontario, with prices starting at $365. Another option worth looking into is United Airlines, starting at $367 round trip. You may be able to fly from San Juan to Ontario for 19% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from San Juan to Ontario one-way?

    One-way options have recently been found by users for as low as $178 on American Airlines. Other airlines that offer cheap prices include Southwest from $192 and United Airlines from $228 one-way.

  • Can I find deals for flights from San Juan to Ontario that include hotel bookings?

    Yes. In addition to deals on San Juan to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from San Juan to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from San Juan to Ontario.

  • Can I find deals for business class flights from San Juan to Ontario?

    Yes. Cheapflights offers flight deals from San Juan to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from San Juan to Ontario?

    Currently, May is the cheapest month in which you can book a flight from San Juan to Ontario (average of $283). Flying from San Juan to Ontario in March is currently the most expensive (average of $556). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Top 2 airlines flying from San Juan to Ontario

Discover the top 2 airlines that operate flights from San Juan to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$365Average$600FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$367Average$520FlexibilityNo cancel feeOn-time69%

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