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$66+ Cheap flights from San Francisco (SFO) to Illinois

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 1/31. Fares are subject to change and may not be available on all flights or dates of travel.
SFO — ORD
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
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Cheap flight deals from San Francisco to Illinois

Cheapest flights from San Francisco to Illinois
Explore the most affordable flight options available from San Francisco to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 12, 2025.

This Kiwi.com deal was found by Cheapflights users on 12/9. 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.
Wed 12/316:24 amSFO - ORD
1 stop15h 48mMultiple Airlines
Tue 1/62:12 pmORD - SFO
1 stop7h 37mMultiple Airlines
Deal found 12/9$269
This Frontier deal was found by Cheapflights users on 12/9. 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 12/186:00 amSFO - ORD
1 stop6h 17mFrontier
Fri 1/95:50 amORD - SFO
1 stop9h 28mFrontier
Deal found 12/9$270
This Kiwi.com deal was found by Cheapflights users on 12/9. 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.
Wed 12/316:24 amSFO - ORD
1 stop15h 48mMultiple Airlines
Sun 1/410:49 pmORD - SFO
2 stops23h 41mMultiple Airlines
Deal found 12/9$271
This Kiwi.com deal was found by Cheapflights users on 12/9. 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.
Wed 12/316:24 amSFO - ORD
1 stop15h 48mFrontier
Sun 1/410:49 pmORD - SFO
2 stops27h 03mFrontier
Deal found 12/9$273
This Expedia deal was found by Cheapflights users on 12/11. 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.
Sun 12/286:24 amSFO - MDW
1 stop13h 26mFrontier
Sat 1/176:10 amMDW - SFO
1 stop9h 14mFrontier
Deal found 12/11$276
This CheapOair deal was found by Cheapflights users on 12/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/112:13 pmSFO - ORD
1 stop19h 29mFrontier
Sun 12/2110:49 pmORD - SFO
1 stop25h 00mFrontier
Deal found 12/9$279
This Cheapflightsfares deal was found by Cheapflights users on 12/9. 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.
Mon 12/156:30 amSFO - ORD
1 stop15h 42mFrontier
Thu 12/183:27 pmORD - SFO
1 stop8h 09mFrontier
Deal found 12/9$283
This Delta deal was found by Cheapflights users on 12/10. 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 12/255:50 amSFO - ORD
1 stop9h 32mDelta
Tue 1/67:30 amORD - SFO
1 stop8h 08mDelta
Deal found 12/10$286
This CheapOair deal was found by Cheapflights users on 12/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3011:20 pmSFO - MDW
1 stop12h 01mFrontier
Fri 1/96:10 amMDW - SFO
1 stop9h 08mFrontier
Deal found 12/10$289
This CheapOair deal was found by Cheapflights users on 12/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/138:43 amSFO - ORD
1 stop24h 59mFrontier
Fri 1/239:38 pmORD - SFO
1 stop14h 30mFrontier
Deal found 12/9$289
This Cheapflightsfares deal was found by Cheapflights users on 12/8. 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.
Sun 12/146:00 amSFO - ORD
1 stop27h 42mFrontier
Thu 12/183:27 pmORD - SFO
1 stop8h 09mFrontier
Deal found 12/8$291
This Kiwi.com deal was found by Cheapflights users on 12/9. 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 12/296:24 amSFO - ORD
1 stop15h 48mMultiple Airlines
Tue 1/67:57 pmORD - SFO
2 stops17h 57mMultiple Airlines
Deal found 12/9$292

Find flight deals from San Francisco to Illinois

Keep the following information in mind while searching for San Francisco to Illinois flight deals. Data was last updated December 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$142
(Kiwi.com)

One-way from

$66
(WAYA)

Popular in

December

Cheapest in

February

Average price

$457

Good round-trip deal

$322 or less

Good one-way deal

$168 or less
Provider with most accurate pricing for San Francisco-Chicago (CHI) flight deals.
Search Deals
Provider most trusted by Cheapflights users for San Francisco-Chicago (CHI) flights.
Search Deals
From San Francisco to Illinois
Search Deals
One-way flight from San Francisco to Illinois
Search Deals
Highest demand for flights based on searches. 14% potential increase in price ($58 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 December 2025
Search Deals
Price to beat on a round-trip flight from San Francisco to Illinois.
Search Deals
Price to beat on a one-way flight from San Francisco to Illinois.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from San Francisco to Illinois 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 December 12, 2025.
Use the filters below to find and compare flights from San Francisco to Illinois that are best for you.

Fly from

San Francisco

Fly to

Illinois

Route

Depart

Return

Price

San FranciscoSt. Louis

SFO - STL

SFOSTL

San Francisco

Tue 2/24

6:55 am-6:51 am

2 stops21h 56m

Lambert-St Louis

Wed 2/25

4:51 pm-12:28 am

1 stop9h 37m

$207

San FranciscoSt. Louis

SFO - STL

SFOSTL

San Francisco

Sat 1/10

10:35 am-11:25 pm

2 stops10h 50m

Lambert-St Louis

Sat 1/17

7:00 am-5:49 pm

2 stops12h 49m

$254

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Thu 1/1

10:45 pm-9:01 am

1 stop8h 16m

Chicago O'Hare Intl

Tue 1/6

2:20 pm-11:28 pm

1 stop11h 08m

$270

San FranciscoChicago

SFO - MDW

SFOMDW

San Francisco

Sat 2/28

6:55 am-12:55 pm

Nonstop4h 00m

Chicago Midway

Mon 3/2

8:15 am-11:15 am

Nonstop5h 00m

$273

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Tue 1/6

11:56 pm-6:25 am

Nonstop4h 29m

Chicago O'Hare Intl

Thu 1/8

6:29 pm-9:30 pm

Nonstop5h 01m

$273

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Fri 2/6

2:30 pm-11:50 pm

1 stop7h 20m

Chicago O'Hare Intl

Tue 3/31

3:20 pm-10:10 pm

1 stop8h 50m

$273

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Sat 1/31

2:35 pm-11:53 pm

1 stop7h 18m

Chicago O'Hare Intl

Sun 2/1

6:15 am-2:40 pm

2 stops10h 25m

$275

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Tue 1/6

5:45 am-5:26 pm

1 stop9h 41m

Chicago O'Hare Intl

Tue 1/13

2:20 pm-10:55 pm

2 stops10h 35m

$275

San FranciscoChicago

SFO - MDW

SFOMDW

San Francisco

Wed 2/4

5:05 am-2:45 pm

1 stop7h 40m

Chicago Midway

Sat 2/7

8:15 am-11:15 am

Nonstop5h 00m

$280

San FranciscoChicago

SFO - ORD

SFOORD

San Francisco

Thu 1/22

2:35 pm-11:53 pm

1 stop7h 18m

Chicago O'Hare Intl

Thu 1/29

8:50 am-7:23 pm

2 stops12h 33m

$282

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/10

Showing 1-10 of 60 results
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Best time to book a flight from San Francisco to Illinois

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

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

Currently, December is the cheapest month in which you can book a flight from San Francisco to Illinois (average of $107). Flying from San Francisco to Illinois in November is currently the most expensive (average of $210). 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 SFO to IL?

Find hourly flight availability from San Francisco to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 12, 2025.

It’s optimal to fly from San Francisco to Illinois in the evening. By choosing this option you can save up to 25% on the cost of your flight, compared to a flight in the afternoon.

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

Use this chart to determine the cheapest time to fly round-trip from San Francisco to Illinois. Price data was last updated on December 16, 2024.

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

Weekly flight availability from San Francisco to Illinois

Explore weekly flight availability from San Francisco to Illinois. 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 December 12, 2025.

The most flights from SFO to USIL are scheduled on a Wednesday (62 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (43 on average).

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated December 12, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest, and United Airlines from San Francisco to Illinois by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Alaska Airlines
8.0
Very good
11,431 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Southwest
7.9
Good
4,253 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
United Airlines
7.4
Good
9,095 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
American Airlines
7.2
Good
11,049 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Frontier
5.8
Fair
3,084 reviews
Alaska Airlines
8.0
Very good
11,431 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.

Related info for your journey

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

    Most people fly from San Francisco (SFO) if they book a flight from San Francisco to Illinois. San Francisco is conveniently located just 11.8 mi from San Francisco’s city center.

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

    For as low as $273, Frontier can have you in Illinois from San Francisco in 4h. Airlines will cover a distance of 1849 mi. This flight may include one or multiple stops.

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

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $64. Alaska Airlines flights start at $98 while deals on Hawaiian Airlines start at $98 one-way.

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

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

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

    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 San Francisco to Illinois on time: China Southern (93%), Fiji Airways (92%), Asiana Airlines (92%).

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

    Looking at all options, your cheapest flight can be booked for $127. While the most popular route (San Francisco - Chicago O'Hare Intl) can be booked for $141 on average, our data indicates $1,108 when flying from San Francisco to Illinois.

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

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

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

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

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

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

    Currently, December is the cheapest month in which you can book a flight from San Francisco to Illinois (average of $107). Flying from San Francisco to Illinois in November is currently the most expensive (average of $210). 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 San Francisco to Illinois

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

Discover the top 7 airlines that operate flights from San Francisco to Illinois. 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 December 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapest$108Average$288FlexibilityNo cancel feeOn-time85%
FrontierCheapest$128Average$240FlexibilityNo cancel feeOn-time62%
DeltaCheapest$128Average$317FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$133Average$456FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$185Average$350FlexibilityNo cancel feeOn-time63%
Alaska AirlinesCheapest$196Average$330FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$197Average$465FlexibilityNo cancel feeOn-time71%

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