$74+ 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 3/6. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SFO
Mar 5 — Mar 121
1 adult, Economy
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Find cheap flights from Illinois to San Francisco with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Illinois to San Francisco
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Cheapest flights from Illinois to San FranciscoExplore 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 February 3, 2026.
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 February 3, 2026.
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/68:12 pm
STL
- SFO
2 stops24h 18m
Frontier
Tue 3/109:04 pm
SFO
- STL
1 stop10h 45m
Frontier
Deal found 2/1![Frontier logo]()
$189
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/231:54 pm
STL
- SFO
1 stop12h 34m
Frontier
Wed 2/257:20 am
SFO
- STL
1 stop6h 33m
Frontier
Deal found 2/2![Frontier logo]()
$190
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/28:22 pm
STL
- SFO
2 stops27h 39m
Frontier
Mon 3/99:24 pm
SFO
- STL
1 stop19h 47m
Frontier
Deal found 2/2![Frontier logo]()
$192
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/45:18 pm
STL
- SFO
1 stop9h 10m
Frontier
Tue 3/106:00 am
SFO
- STL
2 stops26h 37m
Frontier
Deal found 2/1![Frontier logo]()
$193
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/279:02 pm
STL
- SFO
1 stop22h 56m
Frontier
Mon 3/210:58 pm
SFO
- STL
1 stop29h 53m
Frontier
Deal found 2/1![Frontier logo]()
$201
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/282:51 pm
STL
- SFO
1 stop11h 37m
Frontier
Mon 3/210:58 pm
SFO
- STL
1 stop29h 53m
Frontier
Deal found 2/1![Frontier logo]()
$203
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/210:11 pm
STL
- SFO
1 stop22h 09m
Frontier
Thu 3/58:43 am
SFO
- STL
1 stop24h 36m
Frontier
Deal found 2/2![Frontier logo]()
$204
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/243:49 pm
STL
- SFO
2 stops31h 50m
Frontier
Tue 3/38:25 am
SFO
- STL
1 stop29h 28m
Frontier
Deal found 2/2![Frontier logo]()
$208
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/271:59 pm
STL
- SFO
1 stop20h 04m
Frontier
Sun 3/18:48 am
SFO
- STL
1 stop26h 21m
Frontier
Deal found 2/2![Frontier logo]()
$210
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/142:51 pm
STL
- SFO
1 stop11h 37m
Frontier
Sat 2/216:15 am
SFO
- STL
1 stop5h 41m
Frontier
Deal found 2/1![Frontier logo]()
$211
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/2610:11 pm
STL
- SFO
1 stop11h 37m
Frontier
Sun 3/16:15 am
SFO
- STL
1 stop28h 54m
Frontier
Deal found 2/1![Frontier logo]()
$214
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.
Wed 4/157:41 am
ORD
- SFO
2 stops11h 11m
Multiple Airlines
Sun 4/199:33 pm
SFO
- ORD
1 stop7h 14m
Multiple Airlines
Deal found 1/31![Multiple Airlines logo]()
$242
Best flights from Illinois to San FranciscoDiscover carefully curated flight deals from Illinois to San Francisco that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 3, 2026.
Discover carefully curated flight deals from Illinois to San Francisco that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 3, 2026.
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/45:18 pm
STL
- SFO
2 stops16h 02m
Frontier
Wed 3/117:32 pm
SFO
- STL
1 stop21h 39m
Frontier
Deal found 2/2![Frontier logo]()
$227
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/119:05 pm
MDW
- SFO
Nonstop4h 40m
Southwest
Wed 3/1810:55 pm
SFO
- MDW
1 stop8h 25m
Southwest
Deal found 2/1![Southwest logo]()
$247
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.
Wed 2/256:25 am
ORD
- SFO
Nonstop5h 02m
United Airlines
Mon 3/211:59 pm
SFO
- ORD
Nonstop4h 20m
United Airlines
Deal found 2/2![United Airlines logo]()
$250
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.
Wed 3/41:29 pm
MDW
- SFO
1 stop7h 07m
Delta
Mon 3/99:35 pm
SFO
- MDW
1 stop10h 21m
Delta
Deal found 2/1![Delta logo]()
$252
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.
Tue 4/147:05 pm
PIA
- SFO
1 stop6h 54m
American Airlines
Sat 4/183:02 pm
SFO
- PIA
1 stop6h 31m
American Airlines
Deal found 2/2![American Airlines logo]()
$309
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/247:00 am
STL
- SFO
1 stop9h 02m
Alaska Airlines
Tue 2/246:27 pm
SFO
- STL
1 stop17h 24m
Alaska Airlines
Deal found 2/2![Alaska Airlines logo]()
$330
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/17:55 am
MDW
- SFO
Nonstop5h 00m
Southwest
Tue 3/105:40 am
SFO
- MDW
Nonstop4h 00m
Southwest
Deal found 2/2![Southwest logo]()
$250
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.
Thu 4/301:23 pm
MDW
- SFO
1 stop7h 40m
Delta
Tue 5/512:06 pm
SFO
- MDW
1 stop8h 22m
Delta
Deal found 2/1![Delta logo]()
$252
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/159:00 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Fri 4/175:15 am
SFO
- MDW
Nonstop4h 10m
Southwest
Deal found 1/31![Southwest logo]()
$250
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/235:37 pm
ORD
- SFO
1 stop7h 48m
Delta
Tue 3/32:05 pm
SFO
- ORD
1 stop7h 51m
Delta
Deal found 2/2![Delta logo]()
$252
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/156:17 am
ORD
- SFO
Nonstop5h 05m
United Airlines
Sat 3/216:44 pm
SFO
- ORD
Nonstop4h 15m
United Airlines
Deal found 1/31![United Airlines logo]()
$282
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 3/167:10 pm
ORD
- SFO
1 stop6h 49m
Delta
Tue 3/175:50 am
SFO
- ORD
1 stop8h 53m
Delta
Deal found 2/1![Delta logo]()
$252
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/186:00 am
MDW
- SFO
1 stop6h 25m
Southwest
Tue 4/282:50 pm
SFO
- MDW
1 stop6h 30m
Southwest
Deal found 1/31![Southwest logo]()
$254
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.
Mon 3/25:23 pm
PIA
- SFO
1 stop7h 47m
American Airlines
Sun 3/812:30 am
SFO
- PIA
1 stop8h 09m
American Airlines
Deal found 2/1![American Airlines logo]()
$309
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.
Fri 5/1510:45 pm
ORD
- SFO
Nonstop4h 50m
United Airlines
Sun 5/1711:56 pm
SFO
- ORD
Nonstop4h 24m
United Airlines
Deal found 2/1![United Airlines logo]()
$283
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/15:37 pm
ORD
- SFO
1 stop7h 48m
Delta
Tue 3/310:00 pm
SFO
- ORD
1 stop8h 41m
Delta
Deal found 1/31![Delta logo]()
$252
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/72:46 pm
BMI
- SFO
1 stop9h 52m
American Airlines
Tue 5/126:00 am
SFO
- BMI
1 stop6h 16m
American Airlines
Deal found 2/3![American Airlines logo]()
$309
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.
Fri 3/66:17 am
ORD
- SFO
Nonstop5h 05m
United Airlines
Mon 3/166:44 pm
SFO
- ORD
Nonstop4h 15m
United Airlines
Deal found 2/2![United Airlines logo]()
$283
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/1910:11 pm
STL
- SFO
2 stops11h 52m
Frontier
Sun 2/228:48 am
SFO
- STL
1 stop26h 21m
Frontier
Deal found 2/2![Frontier logo]()
$345
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/48:10 am
MDW
- SFO
1 stop7h 35m
Southwest
Sun 3/85:05 am
SFO
- MDW
Nonstop4h 00m
Southwest
Deal found 2/2![Southwest logo]()
$260
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/262:47 pm
STL
- SFO
1 stop9h 08m
Alaska Airlines
Sun 3/17:50 am
SFO
- STL
2 stops14h 09m
Alaska Airlines
Deal found 2/2![Alaska Airlines logo]()
$368
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.
Wed 3/43:45 pm
BMI
- SFO
1 stop8h 22m
American Airlines
Wed 3/116:00 am
SFO
- BMI
1 stop6h 26m
American Airlines
Deal found 2/2![American Airlines logo]()
$309
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/910:05 am
MDW
- SFO
1 stop8h 00m
Southwest
Wed 3/115:40 am
SFO
- MDW
Nonstop4h 00m
Southwest
Deal found 2/2![Southwest logo]()
$260
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.
Thu 3/127:45 am
ORD
- SFO
Nonstop5h 10m
United Airlines
Sun 3/2211:59 pm
SFO
- ORD
Nonstop4h 20m
United Airlines
Deal found 2/2![United Airlines logo]()
$288
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/21:29 pm
MDW
- SFO
1 stop7h 07m
Delta
Mon 3/910:40 pm
SFO
- MDW
1 stop8h 13m
Delta
Deal found 2/2![Delta logo]()
$267
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 3/231:19 pm
ORD
- SFO
1 stop7h 00m
Delta
Mon 3/3010:40 pm
SFO
- ORD
1 stop8h 30m
Delta
Deal found 2/1![Delta logo]()
$267
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/159:00 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Mon 4/209:15 pm
SFO
- MDW
1 stop8h 20m
Southwest
Deal found 1/31![Southwest logo]()
$270
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/159:31 pm
ORD
- SFO
Nonstop4h 59m
United Airlines
Mon 5/2510:45 pm
SFO
- ORD
Nonstop4h 23m
United Airlines
Deal found 1/31![United Airlines logo]()
$298
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 3/185:00 am
BMI
- SFO
1 stop8h 40m
American Airlines
Wed 3/2511:32 am
SFO
- BMI
1 stop9h 09m
American Airlines
Deal found 2/1![American Airlines logo]()
$331
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/49:40 pm
MDW
- SFO
Nonstop4h 40m
Southwest
Sun 4/1211:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Deal found 2/1![Southwest logo]()
$270
Last-minute flights from Illinois to San FranciscoDiscover last-minute flight deals from Illinois to San Francisco. Data last updated February 3, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to San Francisco. Data last updated February 3, 2026 and is based on user searches.
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/142:51 pm
STL
- SFO
1 stop11h 37m
Frontier
Sat 2/216:15 am
SFO
- STL
1 stop5h 41m
Frontier
Deal found 2/1![Frontier logo]()
$211
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/231:54 pm
STL
- SFO
1 stop12h 34m
Frontier
Wed 2/257:20 am
SFO
- STL
1 stop6h 33m
Frontier
Deal found 2/2![Frontier logo]()
$190
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/243:49 pm
STL
- SFO
2 stops31h 50m
Frontier
Tue 3/38:25 am
SFO
- STL
1 stop29h 28m
Frontier
Deal found 2/2![Frontier logo]()
$208
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/2610:11 pm
STL
- SFO
1 stop11h 37m
Frontier
Sun 3/16:15 am
SFO
- STL
1 stop28h 54m
Frontier
Deal found 2/1![Frontier logo]()
$214
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/279:02 pm
STL
- SFO
1 stop22h 56m
Frontier
Mon 3/210:58 pm
SFO
- STL
1 stop29h 53m
Frontier
Deal found 2/1![Frontier logo]()
$201
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/271:59 pm
STL
- SFO
1 stop20h 04m
Frontier
Sun 3/18:48 am
SFO
- STL
1 stop26h 21m
Frontier
Deal found 2/2![Frontier logo]()
$210
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/282:51 pm
STL
- SFO
1 stop11h 37m
Frontier
Mon 3/210:58 pm
SFO
- STL
1 stop29h 53m
Frontier
Deal found 2/1![Frontier logo]()
$203
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/28:22 pm
STL
- SFO
2 stops27h 39m
Frontier
Mon 3/99:24 pm
SFO
- STL
1 stop19h 47m
Frontier
Deal found 2/2![Frontier logo]()
$192
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/210:11 pm
STL
- SFO
1 stop22h 09m
Frontier
Thu 3/56:15 am
SFO
- STL
1 stop25h 34m
Frontier
Deal found 2/1![Frontier logo]()
$204
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/45:18 pm
STL
- SFO
1 stop9h 10m
Frontier
Tue 3/106:00 am
SFO
- STL
2 stops26h 37m
Frontier
Deal found 2/1![Frontier logo]()
$193
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/68:12 pm
STL
- SFO
2 stops24h 18m
Frontier
Tue 3/109:04 pm
SFO
- STL
1 stop10h 45m
Frontier
Deal found 2/1![Frontier logo]()
$189
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/189:28 am
ORD
- SFO
1 stop11h 46m
Frontier
Wed 3/256:00 am
SFO
- ORD
2 stops14h 39m
Frontier
Deal found 2/1![Frontier logo]()
$243
One-way flights from Illinois to San FranciscoSearch for one-way flight options from Illinois to San Francisco. Find affordable one-way fares based on user searches. Data last updated February 3, 2026.
Search for one-way flight options from Illinois to San Francisco. Find affordable one-way fares based on user searches. Data last updated February 3, 2026.
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/68:12 pm
STL
- SFO
1 stop23h 36m
Frontier
Deal found 2/1![Frontier logo]()
$74
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/98:12 pm
STL
- SFO
1 stop25h 57m
Frontier
Deal found 2/2![Frontier logo]()
$79
This Orbitz 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/282:51 pm
STL
- SFO
1 stop19h 12m
Frontier
Deal found 2/2![Frontier logo]()
$80
This Trip.com 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/254:51 pm
STL
- SFO
1 stop9h 37m
Frontier
Deal found 2/1![Frontier logo]()
$87
This Super.com 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/2610:11 pm
STL
- SFO
1 stop11h 37m
Frontier
Deal found 2/2![Frontier logo]()
$88
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/2310:11 pm
STL
- SFO
1 stop22h 09m
Frontier
Deal found 2/2![Frontier logo]()
$90
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/28:22 pm
STL
- SFO
2 stops27h 39m
Frontier
Deal found 2/2![Frontier logo]()
$93
This Super.com 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/2412:14 pm
STL
- SFO
1 stop8h 23m
Frontier
Deal found 2/2![Frontier logo]()
$94
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/1112:14 pm
STL
- SFO
1 stop8h 23m
Frontier
Deal found 2/1![Frontier logo]()
$95
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/308:12 pm
STL
- SFO
1 stop30h 16m
Frontier
Deal found 2/2![Frontier logo]()
$97
This Super.com 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/184:51 pm
STL
- SFO
1 stop17h 12m
Frontier
Deal found 2/1![Frontier logo]()
$99
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/55:16 pm
MDW
- SFO
2 stops50h 32m
Frontier
Deal found 2/1![Frontier logo]()
$123
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 February 3, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $189 (Kiwi.com) |
One-way from | $74 (Kiwi.com) |
Popular in | December |
Cheapest in | July |
Average price | $315 |
Good round-trip deal | $259 or less |
Good one-way deal | $141 or less |
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 February 3, 2026.
Use the filters below to find and compare flights from Illinois to San Francisco that are best for you.
Fly from
Illinois
Fly to
San Francisco
Route
Depart
Return
Price
St. LouisSan Francisco
STL - SFO
STLSFO
Lambert-St Louis
Wed 3/4
5:18 pm-7:20 am
2 stops16h 02m
San Francisco
Wed 3/11
7:32 pm-7:11 pm
1 stop21h 39m
$227
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Wed 3/11
9:05 pm-11:45 pm
Nonstop4h 40m
San Francisco
Wed 3/18
10:55 pm-9:20 am
1 stop8h 25m
$247
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Wed 2/25
6:25 am-9:27 am
Nonstop5h 02m
San Francisco
Mon 3/2
11:59 pm-6:19 am
Nonstop4h 20m
$250
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Sun 3/1
7:55 am-10:55 am
Nonstop5h 00m
San Francisco
Tue 3/10
5:40 am-11:40 am
Nonstop4h 00m
$250
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Wed 4/15
9:00 pm-11:35 pm
Nonstop4h 35m
San Francisco
Fri 4/17
5:15 am-11:25 am
Nonstop4h 10m
$250
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Wed 3/4
1:29 pm-6:36 pm
1 stop7h 07m
San Francisco
Mon 3/9
9:35 pm-9:56 am
1 stop10h 21m
$252
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Thu 4/30
1:23 pm-7:03 pm
1 stop7h 40m
San Francisco
Tue 5/5
12:06 pm-10:28 pm
1 stop8h 22m
$252
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Mon 2/23
5:37 pm-11:25 pm
1 stop7h 48m
San Francisco
Tue 3/3
2:05 pm-11:56 pm
1 stop7h 51m
$252
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Mon 3/16
7:10 pm-11:59 pm
1 stop6h 49m
San Francisco
Tue 3/17
5:50 am-4:43 pm
1 stop8h 53m
$252
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Sun 3/1
5:37 pm-11:25 pm
1 stop7h 48m
San Francisco
Tue 3/3
10:00 pm-8:41 am
1 stop8h 41m
$252
Showing 1-10 of 60 results
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.
STL-SFO
ORD-SFO
MDW-SFO
PIA-SFO
BMI-SFO
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
USIL-SFO
STL-SFO
ORD-SFO
MDW-SFO
PIA-SFO
What is the cheapest month to book a flight from Illinois to San Francisco?
Currently, October is the cheapest month in which you can book a flight from Illinois to San Francisco (average of $80). Flying from Illinois to San Francisco in November is currently the most expensive (average of $207). 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 February 3, 2026.
It’s optimal to fly from Illinois to San Francisco in the evening. By choosing this option you can save up to 19% on the cost of your flight, compared to a flight in the afternoon.
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 January 31, 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.
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 February 3, 2026.
The most flights from USIL to SFO are scheduled on a Friday (54 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (30 on average).
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.
Traveling to a place near San Francisco?
Book flights to San Francisco if you plan to visit one of these locationsSouth San Francisco
Santa Cruz
Santa Clara
Roseville
Livermore
Watsonville
San Bruno
Daly City
Sunnyvale
Turlock
Vacaville
San Carlos
San Ramon
San Lorenzo
Davis
Hollister
Redwood City
Manteca
Union City
Elk Grove
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes for Illinois to San Francisco
See prices for flight routes from nearby airports that may be better suited for you.
Top 9 airlines flying from Illinois to San Francisco
Discover the top 9 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 February 3, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$90 | Average$222 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$108 | Average$217 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$112 | Average$374 | FlexibilityNo cancel fee | On-time83% | |
| Cheapest$128 | Average$325 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$138 | Average$387 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$183 | Average$304 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$187 | Average$281 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$197 | Average$459 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$207 | Average$407 | FlexibilityNo cancel fee | On-time69% |