San Juan

$144+ Cheap flights from Ontario (ONT) to San Juan

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 2/21. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SJU
Mar 6 — Mar 131
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Cheap flight deals from Ontario to San Juan

Cheapest flights from Ontario to San Juan
Explore the most affordable flight options available from Ontario to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 4, 2026.

This United Airlines deal was found by Cheapflights users on 2/1. 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.
Sat 4/257:00 am
ONT
-
SJU
1 stop10h 34m
United Airlines
Sat 5/27:40 am
SJU
-
ONT
1 stop13h 21m
United Airlines
Deal found 2/1$284
This Kiwi.com deal was found by Cheapflights users on 1/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/75:18 pm
ONT
-
SJU
1 stop14h 49m
Multiple Airlines
Mon 4/139:10 pm
SJU
-
ONT
2 stops29h 45m
Multiple Airlines
Deal found 1/31$315
This Delta deal was found by Cheapflights users on 2/1. 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 3/25:00 pm
ONT
-
SJU
2 stops16h 01m
Delta
Fri 3/66:15 am
SJU
-
ONT
1 stop9h 47m
Delta
Deal found 2/1$336
This United Airlines deal was found by Cheapflights users on 2/3. 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 4/295:10 am
ONT
-
SJU
2 stops13h 14m
United Airlines
Thu 5/71:40 pm
SJU
-
ONT
1 stop9h 56m
United Airlines
Deal found 2/3$342
This United Airlines deal was found by Cheapflights users on 2/1. 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.
Mon 10/126:30 pm
ONT
-
SJU
2 stops15h 04m
United Airlines
Fri 10/162:55 pm
SJU
-
ONT
1 stop9h 26m
United Airlines
Deal found 2/1$348
This American Airlines deal was found by Cheapflights users on 2/2. 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 2/215:02 pm
ONT
-
SJU
2 stops12h 58m
American Airlines
Wed 2/258:00 am
SJU
-
ONT
2 stops12h 19m
American Airlines
Deal found 2/2$350
This Kiwi.com deal was found by Cheapflights users on 1/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/244:00 pm
ONT
-
SJU
1 stop16h 07m
Multiple Airlines
Fri 4/36:55 pm
SJU
-
ONT
2 stops27h 24m
Multiple Airlines
Deal found 1/31$354
This American Airlines deal was found by Cheapflights users on 2/1. 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.
Wed 4/112:22 pm
ONT
-
SJU
2 stops17h 38m
American Airlines
Tue 4/146:56 pm
SJU
-
ONT
2 stops18h 13m
American Airlines
Deal found 2/1$362
This Kiwi.com deal was found by Cheapflights users on 2/3. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/22:06 pm
ONT
-
SJU
1 stop17h 31m
Multiple Airlines
Sat 3/77:00 am
SJU
-
ONT
2 stops20h 59m
Multiple Airlines
Deal found 2/3$365
This American Airlines deal was found by Cheapflights users on 2/4. 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.
Fri 9/1811:59 pm
ONT
-
SJU
1 stop11h 04m
American Airlines
Mon 9/217:05 pm
SJU
-
ONT
2 stops17h 12m
American Airlines
Deal found 2/4$371
This United Airlines deal was found by Cheapflights users on 2/2. 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.
Tue 9/226:53 pm
ONT
-
SJU
2 stops15h 52m
United Airlines
Mon 9/282:55 pm
SJU
-
ONT
1 stop9h 26m
United Airlines
Deal found 2/2$373

Find flight deals from Ontario to San Juan

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to San Juan (PR1). 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 February 4, 2026.

Round-trip from

$284
(American Airlines)

One-way from

$144
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$480
From Ontario to San Juan
One-way flight from Ontario to San Juan
Highest demand for flights based on searches. 13% potential increase in price ($90 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($22 potential savings vs. average RT price).
Average for round-trip flights in February 2026

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to San Juan 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 February 4, 2026.
Use the filters below to find and compare flights from Ontario to San Juan that are best for you.

Fly from

Ontario

Fly to

San Juan

Route

Depart

Return

Price

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Wed 4/29

5:10 am-9:24 pm

2 stops13h 14m

San Juan Luis Munoz Marin Intl

Thu 5/7

1:40 pm-8:36 pm

1 stop9h 56m

$342

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Sat 4/11

6:05 am-8:38 pm

1 stop11h 33m

San Juan Luis Munoz Marin Intl

Thu 4/16

1:40 pm-8:36 pm

1 stop9h 56m

$374

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Sun 4/12

6:05 am-8:38 pm

1 stop11h 33m

San Juan Luis Munoz Marin Intl

Thu 4/16

1:40 pm-8:36 pm

1 stop9h 56m

$374

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Thu 4/23

5:33 pm-2:08 pm

2 stops17h 35m

San Juan Luis Munoz Marin Intl

Tue 4/28

6:49 pm-8:39 pm

1 stop28h 50m

$394

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Fri 5/15

9:55 pm-1:45 pm

1 stop12h 50m

San Juan Luis Munoz Marin Intl

Tue 5/19

5:05 am-4:20 pm

1 stop14h 15m

$397

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Mon 2/16

5:00 pm-1:01 pm

2 stops16h 01m

San Juan Luis Munoz Marin Intl

Fri 2/20

6:15 am-12:02 pm

1 stop9h 47m

$400

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Sat 4/25

5:10 am-8:38 pm

2 stops12h 28m

San Juan Luis Munoz Marin Intl

Tue 5/5

2:55 pm-9:58 pm

1 stop10h 03m

$431

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Wed 5/6

5:00 am-5:38 pm

1 stop9h 38m

San Juan Luis Munoz Marin Intl

Tue 5/12

1:40 pm-8:36 pm

1 stop9h 56m

$431

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Fri 5/15

11:25 pm-1:29 pm

1 stop11h 04m

San Juan Luis Munoz Marin Intl

Sun 5/17

12:00 pm-10:09 pm

1 stop13h 09m

$441

OntarioSan Juan

ONT - SJU

ONTSJU

Ontario

Sun 3/1

7:05 pm-10:00 am

2 stops10h 55m

San Juan Luis Munoz Marin Intl

Thu 3/5

2:23 pm-11:59 pm

2 stops13h 36m

$458

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/2

Showing 1-10 of 23 results
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Best time to book a flight from Ontario to San Juan

Have a flexible travel schedule? Discover the best time to fly to San Juan from Ontario 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 Ontario to San Juan

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to San Juan. Price data was last updated on January 30, 2026.

To ensure you get the cheapest price possible for a flight from Ontario to San Juan, you should look to book at least 24 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, April is the cheapest month in which you can book a flight from Ontario to San Juan (average of $145). Flying from Ontario to San Juan in November is currently the most expensive (average of $286). 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.

Reviews of airlines servicing San Juan

Get insights into the airlines that provide service to San Juan. 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 San Juan. Reviews last updated February 4, 2026.
Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Ontario to San Juan. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Related info for your journey

Find useful and relevant information for your journey from Ontario to San Juan. 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 from for flights from Ontario to San Juan?

    If you book a flight to San Juan from Ontario, you will be flying from Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario. There are 0 flights from Ontario to San Juan per day from 5 different airlines.

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

    Airlines like United Airlines and Delta fly from Ontario to San Juan in about 11h 33m. The time it takes to get you to your destination can typically vary by up to 4h 28m. Airlines will cover a distance of 3334 mi. This flight may include one or multiple stops.

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

    Frontier, at $73, was found to be the cheapest airline from Ontario to San Juan.Alternate airlines to your destination round-trip include Delta and United Airlines. Frontier is currently priced 87% below the average price you’ll pay for this route.

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

    $142 is the cheapest one-way deal found within the past few days, from United Airlines. You may also be able to find cheap deals on Delta and American Airlines, with prices starting from $168 and $178, respectively.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Ontario to San Juan 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 Ontario to San Juan?

    Currently, April is the cheapest month in which you can book a flight from Ontario to San Juan (average of $145). Flying from Ontario to San Juan in November is currently the most expensive (average of $286). 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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Alternative routes for Ontario to San Juan

See prices for flight routes from nearby airports that may be better suited for you.

Top 5 airlines flying from Ontario to San Juan

Discover the top 5 airlines that operate flights from Ontario to San Juan. 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 February 4, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$73Average$467FlexibilityNo cancel feeOn-time62%
DeltaCheapest$292Average$530FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$321Average$536FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$365Average$619FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$480Average$605FlexibilityNo cancel feeOn-time63%

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