San Francisco

$149+ Cheap flights from Islip to San Francisco (ISP - SFO)

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 10/28. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — SFO
oct. 22 — oct. 291
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Cheap flight deals from Islip to San Francisco

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to San Francisco (SFO). 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 septiembre 22, 2025.

Round-trip from

$263
(Frontier)

One-way from

$149
(JetBlue)

Popular in

December

Cheapest in

February

Average price

$402
From Islip Long Island to San Francisco
One-way flight from Islip Long Island to San Francisco
Highest demand for flights based on searches. 7% potential increase in price ($34 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($12 potential savings vs. average RT price).
Average for round-trip flights in September 2025

Find flight deals from Islip to San Francisco

Cheapest flights from Islip to San Francisco
Explore the most affordable flight options available from Islip to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on septiembre 22, 2025.

This Frontier deal was found by Cheapflights users on 9/19. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/99:27 pmISP - SFO
2 stops17h 48mFrontier
jue. 11/131:10 pmSFO - ISP
2 stops18h 27mFrontier
Deal found 9/19$263
This Booking.com deal was found by Cheapflights users on 9/21. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/65:05 pmISP - SFO
2 stops31h 17mFrontier
vie. 10/109:23 pmSFO - ISP
2 stops44h 29mFrontier
Deal found 9/21$283
This JetBlue deal was found by Cheapflights users on 9/21. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/271:57 pmISP - SFO
1 stop12h 34mJetBlue
mié. 10/299:44 pmSFO - ISP
1 stop12h 18mJetBlue
Deal found 9/21$297
This Booking.com deal was found by Cheapflights users on 9/20. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 10/59:49 amISP - SFO
2 stops30h 28mFrontier
jue. 10/96:34 amSFO - ISP
2 stops23h 30mFrontier
Deal found 9/20$325
This Booking.com deal was found by Cheapflights users on 9/22. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 10/79:37 pmISP - SFO
2 stops27h 50mFrontier
sáb. 10/116:44 amSFO - ISP
2 stops23h 15mFrontier
Deal found 9/22$334
This Booking.com deal was found by Cheapflights users on 9/20. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 9/275:05 pmISP - SFO
2 stops18h 10mFrontier
mar. 9/308:00 amSFO - ISP
2 stops23h 40mFrontier
Deal found 9/20$344
This JetBlue deal was found by Cheapflights users on 9/20. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/271:57 pmISP - SFO
1 stop12h 34mJetBlue
vie. 10/319:44 pmSFO - ISP
1 stop12h 18mJetBlue
Deal found 9/20$352
This Frontier deal was found by Cheapflights users on 9/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 10/199:47 pmISP - SFO
2 stops21h 13mFrontier
jue. 10/233:25 pmSFO - ISP
2 stops16h 12mFrontier
Deal found 9/21$383
This Kiwi.com deal was found by Cheapflights users on 9/22. 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.
mar. 10/79:37 pmISP - SFO
2 stops27h 50mMultiple Airlines
sáb. 10/1112:39 pmSFO - ISP
1 stop22h 00mMultiple Airlines
Deal found 9/22$418
This JetBlue deal was found by Cheapflights users on 9/21. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 10/301:57 pmISP - SFO
1 stop12h 34mJetBlue
dom. 11/29:44 pmSFO - ISP
1 stop12h 08mJetBlue
Deal found 9/21$421
This JetBlue deal was found by Cheapflights users on 9/20. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/151:50 pmISP - SFO
1 stop12h 41mJetBlue
lun. 11/247:00 amSFO - ISP
1 stop9h 04mJetBlue
Deal found 9/20$542
This Frontier deal was found by Cheapflights users on 9/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 9/2511:40 amISP - SFO
2 stops14h 22mFrontier
lun. 9/297:07 pmSFO - ISP
2 stops12h 33mFrontier
Deal found 9/20$600

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to San Francisco 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 septiembre 22, 2025.
Use the filters below to find and compare flights from Islip to San Francisco that are best for you.

Fly from

Islip

Fly to

San Francisco

Route

Depart

Return

Price

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

lun. 10/27

1:57 pm-11:31 pm

1 stop12h 34m

San Francisco

mié. 10/29

9:44 pm-1:02 pm

1 stop12h 18m

$297

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

dom. 10/5

9:49 am-1:17 pm

2 stops30h 28m

San Francisco

jue. 10/9

6:34 am-9:04 am

2 stops23h 30m

$325

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

mar. 10/7

9:37 pm-10:27 pm

2 stops27h 50m

San Francisco

sáb. 10/11

6:44 am-8:59 am

2 stops23h 15m

$334

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

lun. 10/27

1:57 pm-11:31 pm

1 stop12h 34m

San Francisco

vie. 10/31

9:44 pm-1:02 pm

1 stop12h 18m

$352

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

mar. 10/7

9:37 pm-10:27 pm

2 stops27h 50m

San Francisco

sáb. 10/11

12:39 pm-1:39 pm

1 stop22h 00m

$418

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

jue. 10/30

1:57 pm-11:31 pm

1 stop12h 34m

San Francisco

dom. 11/2

9:44 pm-12:52 pm

1 stop12h 08m

$421

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

sáb. 11/15

1:50 pm-11:31 pm

1 stop12h 41m

San Francisco

lun. 11/24

7:00 am-7:04 pm

1 stop9h 04m

$542

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

jue. 10/30

1:57 pm-11:31 pm

1 stop12h 34m

San Francisco

sáb. 11/1

9:43 pm-1:52 pm

1 stop13h 09m

$601

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

dom. 11/23

5:50 am-3:05 pm

2 stops12h 15m

San Francisco

dom. 11/30

6:30 am-10:10 pm

2 stops12h 40m

$839

IslipSan Francisco

ISP - SFO

ISPSFO

Islip Long Island

lun. 10/6

8:47 pm-12:05 pm

2 stops18h 18m

San Francisco

vie. 10/10

12:47 pm-8:05 pm

3 stops28h 18m

$892

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/22

Showing 1-10 of 22 results
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Best time to book a flight from Islip to San Francisco

Have a flexible travel schedule? Discover the best time to fly to San Francisco from Islip 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 Islip to San Francisco

What is the cheapest month to book a flight from Islip to San Francisco?

Currently, January is the cheapest month in which you can book a flight from Islip to San Francisco (average of $276). Flying from Islip to San Francisco in June is currently the most expensive (average of $357). 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.

Related info for your journey

Find useful and relevant information for your journey from Islip to San Francisco. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • How long is the flight from Islip to San Francisco?

    JetBlue and Frontier can get you from Islip to San Francisco in just under 12h 34m. Your travel time can differ by up to 17h 54m. There are 2611 mi between Islip and San Francisco. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • Can I find deals for flights from Islip to San Francisco that include hotel bookings?

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

  • How can I find direct flights from Islip to San Francisco?

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

  • Can I find deals for business class flights from Islip to San Francisco?

    Yes. Cheapflights offers flight deals from Islip to San Francisco 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 Islip to San Francisco?

    Currently, January is the cheapest month in which you can book a flight from Islip to San Francisco (average of $276). Flying from Islip to San Francisco in June is currently the most expensive (average of $357). 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

Traveling to a place near San Francisco?

Book flights to San Francisco if you plan to visit one of these locations
Roseville
Santa Cruz
Livermore
South San Francisco
Turlock
Antioch
Watsonville
Santa Clara
Manteca
Sunnyvale
Hollister
Vacaville
Foster City
Union City
Vallejo
Burlingame
Redwood City
San Mateo
San Leandro
Lathrop

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