ISP - ONT

$202 Find Cheap Flights from Islip to Ontario - Compare and Save

1 adult
1 adult, Economy, 0 bags

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Everything you should know

Cheapest round-trip
$567
Typical prices: $425-$572
Southwest
Sat 10/6Sat 10/20
ISP - ONT • 2 stops
Cheapest one-way
$202
Typical prices: $212-$443
Frontier
Fri 10/26
ISP - ONT • 2 stops
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Flight Deals

Cheap Flights from Islip to Ontario (ISP-ONT)

 
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Islip to Ontario

Tue, Oct 6 - Tue, Oct 20
Southwest Logo
12:50 pm - 9:25 pmISP  Islip Long Island-ONT Ontario
11h 35m2 stops Baltimore/Washington Las Vegas Harry Reid Intl
Southwest Logo
8:35 am - 8:00 pmONT  Ontario-ISP Islip Long Island
8h 25m2 stops Nashville Intl Baltimore/Washington
$567Southwest
Tue, Oct 6 - Tue, Oct 20
Southwest Logo
6:05 am - 2:45 pmISP  Islip Long Island-ONT Ontario
11h 40m2 stops Baltimore/Washington Houston Hobby
Southwest Logo
8:35 am - 10:40 pmONT  Ontario-ISP Islip Long Island
11h 05m2 stops Nashville Intl Baltimore/Washington
$603Southwest
Tue, Oct 6 - Wed, Oct 7
Frontier Logo
5:43 pm - 10:30 amISP  Islip Long Island-ONT Ontario
19h 47m2 stops Orlando Denver Intl
Frontier Logo
2:30 pm - 5:30 pmONT  Ontario-ISP Islip Long Island
24h 00m2 stops Las Vegas Harry Reid Intl Orlando
$606Frontier
Sun, Nov 8 - Sat, Nov 14
Frontier Logo
6:33 pm - 10:35 amISP  Islip Long Island-ONT Ontario
19h 02m2 stops Orlando Denver Intl
Frontier Logo
6:25 am - 5:31 pmONT  Ontario-ISP Islip Long Island
32h 06m2 stops Denver Intl Orlando
$668Frontier
Fri, Nov 6 - Sun, Nov 15
Frontier Logo
6:54 pm - 11:51 pmISP  Islip Long Island-ONT Ontario
31h 57m2 stops Orlando Denver Intl
Frontier Logo
11:52 am - 5:56 pmONT  Ontario-ISP Islip Long Island
27h 04m2 stops Denver Intl Orlando
$670Frontier
Sat, Nov 21 - Sun, Nov 22
Frontier Logo
4:43 pm - 6:20 amISP  Islip Long Island-ONT Ontario
16h 37m2 stops Orlando Dallas/Fort Worth
Frontier Logo
6:08 pm - 3:45 pmONT  Ontario-ISP Islip Long Island
42h 37m2 stops Dallas/Fort Worth Orlando
$748Frontier
Wed, Dec 23 - Thu, Dec 31
Frontier Logo
9:56 am - 6:15 amISP  Islip Long Island-ONT Ontario
23h 19m2 stops Orlando Las Vegas Harry Reid Intl
Frontier Logo
4:46 pm - 9:01 amONT  Ontario-ISP Islip Long Island
13h 15m2 stops Denver Intl Orlando
$923Frontier
Wed, Oct 21 - Wed, Oct 28
Multiple Airlines Logo
12:30 pm - 12:18 pmISP  Islip Long Island-ONT Ontario
26h 48m2 stops Boston Logan Intl San Francisco
Multiple Airlines Logo
5:00 am - 11:09 amONT  Ontario-ISP Islip Long Island
27h 09m2 stops Denver Intl Boston Logan Intl
$1,016Multiple Airlines
Sat, Oct 10 - Sun, Oct 11
Frontier Logo
6:25 pm - 10:29 amISP  Islip Long Island-ONT Ontario
19h 04m2 stops Orlando Denver Intl
Frontier Logo
1:38 pm - 6:00 pmONT  Ontario-ISP Islip Long Island
25h 22m2 stops Las Vegas Harry Reid Intl Orlando
$1,087Frontier
Tue, Oct 6 - Tue, Oct 20
Multiple Airlines Logo
7:31 am - 10:49 pmISP  Islip Long Island-ONT Ontario
18h 18m2 stops Boston Logan Intl Chicago O'Hare Intl
Multiple Airlines Logo
1:22 pm - 11:09 amONT  Ontario-ISP Islip Long Island
18h 47m2 stops Denver Intl Boston Logan Intl
$1,105Multiple Airlines
Booking Insights

Price, demand and travel trends for Islip to Ontario flights

Use KAYAK data on prices, travel dates, airlines and seasonal trends to compare options and book flights with more confidence.

How much is a round-trip flight from Islip to Ontario?

Round-trip flights from Islip to Ontario typically range from $425 to $572. The lowest price found in the past 5 days was $567, on Southwest.

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Key details for Islip to Ontario flights

Cheapest flight

$202
One-way flight from Islip to Ontario

When to book flights from Islip to Ontario

Are your dates flexible? Find out the best times to travel from Islip to Ontario based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

Your Islip to Ontario flight questions, answered

Find helpful answers about this route, including flight times, airports, airlines and booking tips.

  • What cabin classes can I book on flights from Islip to Ontario?

    Only Economy Class is available on flights from Islip to Ontario.

  • Do I need a passport to fly from Islip to Ontario?

    No, a passport is not required for this domestic route, but you will need a real ID-compliant driver's license, a state ID or another TSA-accepted form of identification.

  • Have flight prices from Islip to Ontario changed much recently?

    Yes. Based on fares seen in the past 5 days, round-trip prices on this route showed a wide range, from about $567 to $1,525. That means the highest observed fare was about 3x higher than the lowest one.

  • How are flight prices from Islip to Ontario looking right now?

    One-way fares from Islip to Ontario are currently lower than usual. Average one-way flight prices are about $276, which is 38% below the typical average for this route.

  • What car rental options are available at Ontario Airport (ONT)?

    Ontario Airport (ONT) hosts 5 major car rental companies, with daily rates starting from around $18 for economy cars. Top options include:

    • Fox
    • Thrifty
    • Europcar
    • Dollar
    • Alamo

  • Which airports can I use when flying from Islip to Ontario?

    Flights from Islip to Ontario usually depart from Islip Long Island (ISP) and arrive at Ontario (ONT).

  • Which airports do connecting flights from Islip to Ontario pass through?

    Most connecting flights from Islip to Ontario pass through Baltimore/Washington (BWI), which handles 100% of one-stop traffic on this route.

  • Can I save money by using flexible dates for flights from Islip to Ontario?

    Yes. Flexible dates can save you up to 62% on flights from Islip to Ontario. Tuesday is the cheapest departure day at $425 round-trip on average, while Friday is the most expensive at $1,106, a difference of $681.

    KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

  • What is the time difference between Islip and Ontario?

    Ontario is 3 hours behind Islip (Pacific Time vs Eastern Time). Plan for the time shift when scheduling connections or first-day activities.

  • What popular places can I visit in Ontario?

    Some of the most popular sights in Ontario are Ontario Convention Center and Cucamonga-Guasti Regional Park. These are among the most viewed places in Ontario on KAYAK.

Your guide to booking Islip to Ontario flights

Get tips on when to book, when to fly and what to know before your trip.

More options for your flight from Islip to Ontario

Complete your trip to Ontario with a hotel stay or car rental

Car rentals in Ontario
Hotels in Ontario
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