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$104+ Cheap flights from Illinois to San Francisco (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 8/17. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SFO
Jul 21 — Jul 281
Tue 7/21
Tue 7/28
1 adult, Economy
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Cheap flight deals from Illinois to San Francisco

Cheapest flights from Illinois to San Francisco
Explore the most affordable flight options available from Illinois to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 21, 2026.

This Frontier deal was found by Cheapflights users on 6/16. 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.
Thu 10/156:05 am
ORD
-
SFO
1 stop13h 35m
Frontier
Wed 10/217:17 pm
SFO
-
ORD
1 stop12h 44m
Frontier
Deal found 6/16$297
This Kiwi.com deal was found by Cheapflights users on 6/16. 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 7/279:57 pm
ORD
-
SFO
1 stop15h 46m
Frontier
Wed 8/54:30 pm
SFO
-
ORD
1 stop11h 07m
Frontier
Deal found 6/16$298
This Expedia deal was found by Cheapflights users on 6/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/54:45 pm
MDW
-
SFO
1 stop8h 09m
Frontier
Sun 8/910:10 pm
SFO
-
MDW
1 stop9h 41m
Frontier
Deal found 6/16$299
This Frontier deal was found by Cheapflights users on 6/16. 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.
Sun 11/17:00 am
ORD
-
SFO
1 stop8h 17m
Frontier
Tue 11/104:00 pm
SFO
-
ORD
1 stop11h 35m
Frontier
Deal found 6/16$299
This Kiwi.com deal was found by Cheapflights users on 6/16. 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 7/287:15 am
ORD
-
SFO
2 stops16h 23m
Frontier
Tue 8/49:00 pm
SFO
-
ORD
1 stop6h 37m
Frontier
Deal found 6/16$300
This Cheapflightsfares deal was found by Cheapflights users on 6/16. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/319:13 pm
ORD
-
SFO
1 stop25h 32m
Frontier
Mon 8/106:04 pm
SFO
-
ORD
1 stop24h 48m
Frontier
Deal found 6/16$301
This Travelocity deal was found by Cheapflights users on 6/16. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/194:10 pm
MDW
-
SFO
1 stop8h 52m
Frontier
Tue 7/2110:10 pm
SFO
-
MDW
1 stop10h 57m
Frontier
Deal found 6/16$303
This Expedia deal was found by Cheapflights users on 6/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/26:55 am
ORD
-
SFO
1 stop14h 31m
Frontier
Fri 7/109:39 pm
SFO
-
ORD
1 stop21h 13m
Frontier
Deal found 6/16$303
This Frontier deal was found by Cheapflights users on 6/17. 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.
Thu 7/912:11 pm
MDW
-
SFO
1 stop9h 07m
Frontier
Sat 7/1111:00 pm
SFO
-
MDW
1 stop10h 07m
Frontier
Deal found 6/17$304
This Frontier deal was found by Cheapflights users on 6/16. 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.
Wed 7/297:15 am
ORD
-
SFO
1 stop10h 10m
Frontier
Sun 8/912:54 am
SFO
-
ORD
1 stop13h 06m
Frontier
Deal found 6/16$304
This Frontier deal was found by Cheapflights users on 6/16. 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.
Thu 8/1311:06 am
MDW
-
SFO
1 stop10h 07m
Frontier
Sun 8/1610:10 pm
SFO
-
MDW
1 stop9h 41m
Frontier
Deal found 6/16$305
This Frontier deal was found by Cheapflights users on 6/17. 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.
Thu 8/66:05 am
MDW
-
SFO
1 stop15h 08m
Frontier
Sun 8/910:10 pm
SFO
-
MDW
1 stop9h 41m
Frontier
Deal found 6/17$306

Find flight deals from Illinois to San Francisco

Keep the following information in mind while searching for Illinois to San Francisco flight deals. Data was last updated June 21, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$297
(Frontier)

One-way from

$104
(Trip.com)

Popular in

June

Cheapest in

September

Average price

$461

Good round-trip deal

$311 or less

Good one-way deal

$203 or less
Provider with most accurate pricing for Chicago (CHI)-San Francisco flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-San Francisco flights.
Search Deals
From Illinois to San Francisco
Search Deals
One-way flight from Illinois to San Francisco
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($18 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from Illinois to San Francisco.
Search Deals
Price to beat on a one-way flight from Illinois to San Francisco.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Illinois 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 June 21, 2026.
Use the filters below to find and compare flights from Illinois to San Francisco that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

ChicagoSan Francisco

ORD - SFO

ORDSFO

Chicago O'Hare Intl

Tue 7/14

7:30 am-10:19 am

Nonstop4h 49m

San Francisco

Tue 7/21

4:21 pm-10:59 pm

Nonstop4h 38m

$329

ChicagoSan Francisco

ORD - SFO

ORDSFO

Chicago O'Hare Intl

Sat 7/18

6:10 am-8:47 am

Nonstop4h 37m

San Francisco

Mon 7/20

3:10 pm-9:38 pm

Nonstop4h 28m

$332
Quickest round-trip

ChicagoSan Francisco

MDW - SFO

MDWSFO

Chicago Midway

Wed 8/12

10:25 am-12:55 pm

Nonstop4h 30m

San Francisco

Mon 8/17

5:35 am-11:40 am

Nonstop4h 05m

$335

MolineSan Francisco

MLI - SFO

MLISFO

Moline Quad-City

Fri 10/16

5:00 pm-12:15 am

1 stop9h 15m

San Francisco

Sat 10/24

6:00 am-4:22 pm

1 stop8h 22m

$340

ChicagoSan Francisco

ORD - SFO

ORDSFO

Chicago O'Hare Intl

Fri 9/18

7:40 am-10:26 am

Nonstop4h 46m

San Francisco

Tue 9/22

11:30 pm-5:59 am

Nonstop4h 29m

$341

ChicagoSan Francisco

MDW - SFO

MDWSFO

Chicago Midway

Fri 9/4

9:10 pm-11:45 pm

Nonstop4h 35m

San Francisco

Mon 9/7

11:40 pm-5:50 am

Nonstop4h 10m

$344

ChicagoSan Francisco

MDW - SFO

MDWSFO

Chicago Midway

Thu 7/30

9:30 pm-12:15 am

Nonstop4h 45m

San Francisco

Mon 8/3

11:40 pm-5:55 am

Nonstop4h 15m

$344

ChicagoSan Francisco

ORD - SFO

ORDSFO

Chicago O'Hare Intl

Sat 7/11

6:10 am-8:47 am

Nonstop4h 37m

San Francisco

Fri 7/17

3:10 pm-9:38 pm

Nonstop4h 28m

$344

PeoriaSan Francisco

PIA - SFO

PIASFO

Greater Peoria

Wed 7/1

1:13 pm-6:49 pm

1 stop7h 36m

San Francisco

Sat 7/4

12:50 am-10:09 am

1 stop7h 19m

$345

MolineSan Francisco

MLI - SFO

MLISFO

Moline Quad-City

Fri 10/30

5:55 am-1:42 pm

1 stop9h 47m

San Francisco

Mon 11/2

10:30 pm-10:26 am

1 stop9h 56m

$349

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/20

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Illinois to San Francisco

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

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

Currently, September is the cheapest month in which you can book a flight from Illinois to San Francisco (average of $340). Flying from Illinois to San Francisco in June is currently the most expensive (average of $533). 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.

What is the cheapest time of day to fly from IL to SFO?

Find hourly flight availability from Illinois to San Francisco. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 21, 2026.

It’s optimal to fly from Illinois to San Francisco in the morning. By choosing this option you can save up to 14% on the cost of your flight, compared to a flight in the afternoon.

Weekly flight availability from Illinois to San Francisco

Explore weekly flight availability from Illinois to San Francisco. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated June 21, 2026.

The most flights from USIL to SFO are scheduled on a Sunday (94 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (57 on average).

How much does it cost to fly round-trip from Illinois to San Francisco?

How far ahead should I book a flight from Illinois to San Francisco?

Booking 63 days in advance of your planned departure date is, on average, the best time to get cheap flights from Illinois to San Francisco. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest day to fly from Illinois to San Francisco?

Use this chart to determine the cheapest time to fly round-trip from Illinois to San Francisco. Price data was last updated on June 20, 2026.

Travelers seeking maximum savings on their Illinois to San Francisco flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Related info for your journey

Find useful and relevant information for your journey from Illinois to San Francisco. 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 San Francisco from Illinois?

    If you book a flight to San Francisco from Illinois, you will be flying to San Francisco, which is the city’s only airport. San Francisco (SFO) is located 11.0 mi from the center of San Francisco.

  • How long is the flight from Illinois to San Francisco?

    United Airlines, Southwest, and Delta can get you from Illinois to San Francisco in just under 4h 30m. Your travel time can differ by up to 4h 45m. Airlines will cover a distance of 1849 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines to fly from Illinois to San Francisco one-way?

    The cheapest airline one-way is JetBlue, with whom users have recently found tickets for as low as $73. However, be on the lookout for offers from Alaska Airlines and Frontier, as they are both options that can get you from Illinois to San Francisco for a low price.

  • What are the most popular routes from Illinois to San Francisco?

    The most popular route from Illinois to San Francisco is Chicago O'Hare Intl - San Francisco. You may also consider Chicago Midway - San Francisco or Lambert-St Louis - San Francisco.

  • What are the most reliable airlines from Illinois to San Francisco?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Illinois to San Francisco on time: ANA (85%), Air China (76%), China Southern (68%).

  • What are the cheapest flights from Illinois to San Francisco?

    While on average a flight from Illinois to San Francisco is generally $1,106, our data shows the cheapest flight currently is $144. When looking at the most popular route, (Chicago O'Hare Intl - San Francisco), you can expect to pay $246 for that flight.

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

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

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

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

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

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

    Currently, September is the cheapest month in which you can book a flight from Illinois to San Francisco (average of $340). Flying from Illinois to San Francisco in June is currently the most expensive (average of $533). 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
South San Francisco
Santa Cruz
Santa Clara
Fairfield
Rancho Cordova
Roseville
Cupertino
Emeryville
Newark
Watsonville
San Bruno
San Ramon
Vacaville
San Carlos
Redwood City
Daly City
Turlock
Sunnyvale
Vallejo
San Lorenzo

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Alternative routes for Illinois to San Francisco

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from Illinois to San Francisco

Discover the top 7 airlines that operate flights from Illinois to San Francisco. 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 June 21, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$116Average$242FlexibilityNo cancel feeOn-time62%
DeltaCheapest$128Average$395FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$138Average$371FlexibilityNo cancel feeOn-time63%
JetBlueCheapest$159Average$301FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$207Average$465FlexibilityNo cancel feeOn-time71%
Alaska AirlinesCheapest$217Average$390FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$240Average$444FlexibilityNo cancel feeOn-time69%

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