$69+ 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 2/28. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SFO
Mar 12 — Mar 191
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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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 10, 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 10, 2026.
This CheapOair deal was found by Cheapflights users on 2/9. 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 4/168:12 pm
STL
- SFO
1 stop6h 10m
Frontier
Fri 4/179:33 pm
SFO
- STL
1 stop15h 48m
Frontier
Deal found 2/9![Frontier logo]()
$201
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/168:12 pm
STL
- SFO
1 stop30h 16m
Frontier
Mon 3/236:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/7![Frontier logo]()
$202
This Kiwi.com deal was found by Cheapflights users on 2/9. 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.
Tue 4/214:55 pm
STL
- SFO
2 stops32h 30m
Frontier
Sat 4/256:00 am
SFO
- STL
1 stop11h 12m
Frontier
Deal found 2/9![Frontier logo]()
$203
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 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 2/8![Frontier logo]()
$207
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/92:09 pm
STL
- SFO
1 stop31h 05m
Frontier
Mon 3/166:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/8![Frontier logo]()
$209
This Frontier deal was found by Cheapflights users on 2/9. 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.
Wed 2/184:51 pm
STL
- SFO
1 stop9h 37m
Frontier
Sat 2/286:15 am
SFO
- STL
1 stop5h 41m
Frontier
Deal found 2/9![Frontier logo]()
$211
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/178:06 pm
STL
- SFO
1 stop24h 31m
Frontier
Mon 3/236:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/7![Frontier logo]()
$217
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/238:22 pm
STL
- SFO
1 stop27h 17m
Frontier
Fri 2/278:18 pm
SFO
- STL
2 stops15h 38m
Frontier
Deal found 2/8![Frontier logo]()
$218
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/168:12 pm
STL
- SFO
2 stops23h 34m
Frontier
Sun 4/196:00 am
SFO
- STL
1 stop11h 12m
Frontier
Deal found 2/8![Frontier logo]()
$219
This CheapOair deal was found by Cheapflights users on 2/7. 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.
Fri 2/201:59 pm
STL
- SFO
1 stop20h 04m
Frontier
Wed 2/257:20 am
SFO
- STL
1 stop6h 33m
Frontier
Deal found 2/7![Frontier logo]()
$222
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/21:35 pm
MDW
- SFO
2 stops10h 20m
Southwest
Wed 3/46:05 am
SFO
- MDW
1 stop7h 20m
Southwest
Deal found 2/9![Southwest logo]()
$242
This Kiwi.com deal was found by Cheapflights users on 2/9. 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.
Sun 3/14:42 pm
ORD
- SFO
1 stop30h 57m
Frontier
Wed 3/410:58 pm
SFO
- ORD
1 stop9h 53m
Frontier
Deal found 2/9![Frontier 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 10, 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 10, 2026.
This Travelocity deal was found by Cheapflights users on 2/9. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/113:02 pm
STL
- SFO
1 stop9h 29m
Frontier
Fri 5/156:00 am
SFO
- STL
1 stop11h 12m
Frontier
Deal found 2/9![Frontier logo]()
$211
This Delta deal was found by Cheapflights users on 2/9. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/277:16 pm
MDW
- SFO
1 stop6h 38m
Delta
Wed 5/611:59 pm
SFO
- MDW
1 stop6h 43m
Delta
Deal found 2/9![Delta logo]()
$247
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/206:17 am
ORD
- SFO
Nonstop5h 05m
United Airlines
Wed 3/255:15 pm
SFO
- ORD
Nonstop4h 23m
United Airlines
Deal found 2/9![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/129:25 pm
MDW
- SFO
Nonstop4h 40m
Southwest
Mon 3/165:10 am
SFO
- MDW
Nonstop4h 00m
Southwest
Deal found 2/9![Southwest logo]()
$250
This Alaska Airlines deal was found by Cheapflights users on 2/9. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/108:20 am
ORD
- SFO
2 stops12h 24m
Alaska Airlines
Tue 3/174:21 pm
SFO
- ORD
1 stop12h 18m
Alaska Airlines
Deal found 2/9![Alaska Airlines logo]()
$261
This American Airlines deal was found by Cheapflights users on 2/8. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/295:40 pm
PIA
- SFO
1 stop7h 29m
American Airlines
Sat 5/25:32 am
SFO
- PIA
1 stop9h 36m
American Airlines
Deal found 2/8![American Airlines logo]()
$309
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/1912:17 pm
MLI
- SFO
1 stop21h 41m
Multiple Airlines
Tue 3/248:09 pm
SFO
- MLI
2 stops37h 18m
Multiple Airlines
Deal found 2/7![Multiple Airlines logo]()
$397
This Expedia deal was found by Cheapflights users on 2/9. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/109:55 pm
STL
- SFO
1 stop12h 23m
Frontier
Sat 5/166:00 am
SFO
- STL
1 stop11h 12m
Frontier
Deal found 2/9![Frontier logo]()
$211
This Delta deal was found by Cheapflights users on 2/9. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/297:16 pm
MDW
- SFO
1 stop6h 38m
Delta
Wed 5/612:05 am
SFO
- MDW
1 stop6h 37m
Delta
Deal found 2/9![Delta logo]()
$247
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/129:25 pm
MDW
- SFO
Nonstop4h 40m
Southwest
Wed 3/1811:25 pm
SFO
- MDW
Nonstop4h 05m
Southwest
Deal found 2/9![Southwest logo]()
$250
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/79:45 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Sun 5/104:05 pm
SFO
- MDW
1 stop7h 50m
Southwest
Deal found 2/9![Southwest logo]()
$260
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/296:25 am
ORD
- SFO
Nonstop4h 51m
United Airlines
Sun 5/36:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Deal found 2/9![United Airlines logo]()
$294
This Delta deal was found by Cheapflights users on 2/8. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/71:29 pm
MDW
- SFO
1 stop7h 07m
Delta
Sat 3/146:00 am
SFO
- MDW
1 stop7h 25m
Delta
Deal found 2/8![Delta logo]()
$278
This American Airlines deal was found by Cheapflights users on 2/7. 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 4/146:00 am
PIA
- SFO
1 stop8h 38m
American Airlines
Sat 4/185:34 am
SFO
- PIA
1 stop9h 34m
American Airlines
Deal found 2/7![American Airlines logo]()
$309
This Southwest deal was found by Cheapflights users on 2/6. 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.
Tue 3/38:10 am
MDW
- SFO
1 stop7h 35m
Southwest
Thu 3/511:25 pm
SFO
- MDW
Nonstop4h 05m
Southwest
Deal found 2/6![Southwest logo]()
$260
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/253:45 pm
ORD
- SFO
Nonstop4h 53m
United Airlines
Sun 5/36:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Deal found 2/9![United Airlines logo]()
$294
This Kiwi.com deal was found by Cheapflights users on 2/9. 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.
Fri 3/1312:16 pm
STL
- SFO
1 stop8h 58m
Frontier
Mon 3/166:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/9![Frontier logo]()
$298
This American Airlines deal was found by Cheapflights users on 2/8. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/85:26 pm
MLI
- SFO
1 stop7h 31m
American Airlines
Sat 8/155:45 am
SFO
- MLI
1 stop9h 11m
American Airlines
Deal found 2/8![American Airlines logo]()
$309
This Alaska Airlines deal was found by Cheapflights users on 2/7. 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.
Sat 4/187:00 am
STL
- SFO
1 stop17h 27m
Alaska Airlines
Wed 4/228:00 am
SFO
- STL
2 stops13h 59m
Alaska Airlines
Deal found 2/7![Alaska Airlines logo]()
$348
This Southwest deal was found by Cheapflights users on 2/7. 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.
Thu 3/58:15 pm
MDW
- SFO
1 stop6h 35m
Southwest
Wed 3/1810:55 pm
SFO
- MDW
1 stop8h 25m
Southwest
Deal found 2/7![Southwest logo]()
$267
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/77:50 pm
ORD
- SFO
Nonstop5h 06m
United Airlines
Tue 3/103:15 pm
SFO
- ORD
Nonstop4h 22m
United Airlines
Deal found 2/9![United Airlines logo]()
$294
This Delta deal was found by Cheapflights users on 2/6. 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 4/162:20 pm
STL
- SFO
2 stops11h 17m
Delta
Sat 4/1810:32 am
SFO
- STL
2 stops8h 59m
Delta
Deal found 2/6![Delta logo]()
$308
This American Airlines deal was found by Cheapflights users on 2/7. 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 3/1812:40 pm
MLI
- SFO
1 stop10h 16m
American Airlines
Mon 3/2312:25 am
SFO
- MLI
1 stop9h 46m
American Airlines
Deal found 2/7![American Airlines logo]()
$309
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/69:15 pm
ORD
- SFO
Nonstop5h 01m
United Airlines
Mon 3/910:45 pm
SFO
- ORD
Nonstop4h 22m
United Airlines
Deal found 2/9![United Airlines logo]()
$294
This Alaska Airlines deal was found by Cheapflights users on 2/7. 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.
Fri 4/177:00 am
STL
- SFO
1 stop17h 27m
Alaska Airlines
Wed 4/229:20 am
SFO
- STL
2 stops12h 39m
Alaska Airlines
Deal found 2/7![Alaska Airlines logo]()
$358
This Southwest deal was found by Cheapflights users on 2/6. 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.
Tue 3/175:35 pm
MDW
- SFO
1 stop7h 10m
Southwest
Mon 3/239:20 pm
SFO
- MDW
1 stop8h 25m
Southwest
Deal found 2/6![Southwest logo]()
$270
This American Airlines deal was found by Cheapflights users on 2/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/113:45 pm
BMI
- SFO
1 stop9h 31m
American Airlines
Wed 3/186:00 am
SFO
- BMI
1 stop6h 26m
American Airlines
Deal found 2/9![American Airlines logo]()
$309
This Kiwi.com deal was found by Cheapflights users on 2/9. 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 3/238:12 pm
STL
- SFO
1 stop25h 57m
Frontier
Thu 3/269:33 pm
SFO
- STL
2 stops10h 16m
Frontier
Deal found 2/9![Frontier logo]()
$351
This United Airlines deal was found by Cheapflights users on 2/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/283:45 pm
ORD
- SFO
Nonstop4h 53m
United Airlines
Sun 5/36:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Deal found 2/9![United Airlines logo]()
$294
This Southwest deal was found by Cheapflights users on 2/7. 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 5/47:35 pm
ORD
- SFO
2 stops17h 30m
Southwest
Sat 5/911:05 am
SFO
- ORD
1 stop9h 15m
Southwest
Deal found 2/7![Southwest logo]()
$272
Last-minute flights from Illinois to San FranciscoDiscover last-minute flight deals from Illinois to San Francisco. Data last updated February 10, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to San Francisco. Data last updated February 10, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 2/9. 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.
Wed 2/184:51 pm
STL
- SFO
1 stop9h 37m
Frontier
Sat 2/286:15 am
SFO
- STL
1 stop5h 41m
Frontier
Deal found 2/9![Frontier logo]()
$211
This CheapOair deal was found by Cheapflights users on 2/7. 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.
Fri 2/201:59 pm
STL
- SFO
1 stop20h 04m
Frontier
Wed 2/257:20 am
SFO
- STL
1 stop6h 33m
Frontier
Deal found 2/7![Frontier logo]()
$222
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/238:22 pm
STL
- SFO
1 stop27h 17m
Frontier
Fri 2/278:18 pm
SFO
- STL
2 stops15h 38m
Frontier
Deal found 2/8![Frontier logo]()
$218
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 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 2/8![Frontier logo]()
$207
This Kiwi.com deal was found by Cheapflights users on 2/9. 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.
Sun 3/14:42 pm
ORD
- SFO
1 stop30h 57m
Frontier
Wed 3/410:58 pm
SFO
- ORD
1 stop9h 53m
Frontier
Deal found 2/9![Frontier logo]()
$242
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/21:35 pm
MDW
- SFO
2 stops10h 20m
Southwest
Wed 3/46:05 am
SFO
- MDW
1 stop7h 20m
Southwest
Deal found 2/9![Southwest logo]()
$242
This Kiwi.com deal was found by Cheapflights users on 2/9. 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.
Thu 3/510:11 pm
STL
- SFO
1 stop11h 47m
Frontier
Sun 3/810:40 pm
SFO
- STL
1 stop12h 39m
Frontier
Deal found 2/9![Frontier logo]()
$224
This CheapOair deal was found by Cheapflights users on 2/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/78:12 pm
STL
- SFO
1 stop6h 16m
Frontier
Mon 3/99:24 pm
SFO
- STL
1 stop19h 47m
Frontier
Deal found 2/8![Frontier logo]()
$229
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/92:09 pm
STL
- SFO
1 stop31h 05m
Frontier
Mon 3/166:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/8![Frontier logo]()
$209
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/168:12 pm
STL
- SFO
1 stop30h 16m
Frontier
Mon 3/236:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/7![Frontier logo]()
$202
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/178:06 pm
STL
- SFO
1 stop24h 31m
Frontier
Mon 3/236:41 pm
SFO
- STL
2 stops37h 08m
Frontier
Deal found 2/7![Frontier logo]()
$217
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/178:06 pm
STL
- SFO
2 stops27h 32m
Multiple Airlines
Tue 3/249:04 pm
SFO
- STL
1 stop10h 45m
Multiple Airlines
Deal found 2/7![Multiple Airlines logo]()
$227
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 10, 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 10, 2026.
This Trip.com deal was found by Cheapflights users on 2/8. 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 Trip.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
Deal found 2/8![Frontier logo]()
$69
This Trip.com deal was found by Cheapflights users on 2/8. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/188:12 pm
STL
- SFO
1 stop14h 56m
Frontier
Deal found 2/8![Frontier logo]()
$76
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/208:12 pm
STL
- SFO
1 stop29h 13m
Frontier
Deal found 2/10![Frontier logo]()
$77
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 5/48:12 pm
STL
- SFO
1 stop29h 13m
Frontier
Deal found 2/7![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/258:12 pm
STL
- SFO
1 stop14h 56m
Frontier
Deal found 2/10![Frontier logo]()
$82
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/248:12 pm
STL
- SFO
1 stop29h 13m
Frontier
Deal found 2/10![Frontier logo]()
$84
This Super.com deal was found by Cheapflights users on 2/8. 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 Super.com 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
Deal found 2/8![Frontier logo]()
$89
This Trip.com deal was found by Cheapflights users on 2/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/78:12 pm
STL
- SFO
1 stop14h 56m
Frontier
Deal found 2/10![Frontier logo]()
$92
This Kiwi.com deal was found by Cheapflights users on 2/7. 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 3/92:09 pm
STL
- SFO
2 stops32h 00m
Frontier
Deal found 2/7![Frontier logo]()
$93
This Super.com deal was found by Cheapflights users on 2/9. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/188:12 pm
STL
- SFO
1 stop6h 16m
Frontier
Deal found 2/9![Frontier logo]()
$94
This Southwest deal was found by Cheapflights users on 2/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/1110:05 am
MDW
- SFO
1 stop8h 25m
Southwest
Deal found 2/9![Southwest logo]()
$119
This Delta deal was found by Cheapflights users on 2/9. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/25:37 pm
ORD
- SFO
1 stop7h 48m
Delta
Deal found 2/9![Delta logo]()
$119
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 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $201 (CheapOair) |
One-way from | $69 (Trip.com) |
Popular in | December |
Cheapest in | July |
Average price | $397 |
Good round-trip deal | $283 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 10, 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
Mon 5/11
3:02 pm-10:31 pm
1 stop9h 29m
San Francisco
Fri 5/15
6:00 am-7:12 pm
1 stop11h 12m
$211
St. LouisSan Francisco
STL - SFO
STLSFO
Lambert-St Louis
Sun 5/10
9:55 pm-8:18 am
1 stop12h 23m
San Francisco
Sat 5/16
6:00 am-7:12 pm
1 stop11h 12m
$211
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Mon 4/27
7:16 pm-11:54 pm
1 stop6h 38m
San Francisco
Wed 5/6
11:59 pm-8:42 am
1 stop6h 43m
$247
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Fri 3/20
6:17 am-9:22 am
Nonstop5h 05m
San Francisco
Wed 3/25
5:15 pm-11:38 pm
Nonstop4h 23m
$247
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Wed 4/29
7:16 pm-11:54 pm
1 stop6h 38m
San Francisco
Wed 5/6
12:05 am-8:42 am
1 stop6h 37m
$247
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Thu 3/12
9:25 pm-12:05 am
Nonstop4h 40m
San Francisco
Mon 3/16
5:10 am-11:10 am
Nonstop4h 00m
$250
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Thu 3/12
9:25 pm-12:05 am
Nonstop4h 40m
San Francisco
Wed 3/18
11:25 pm-5:30 am
Nonstop4h 05m
$250
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Thu 5/7
9:45 pm-12:20 am
Nonstop4h 35m
San Francisco
Sun 5/10
4:05 pm-1:55 am
1 stop7h 50m
$260
ChicagoSan Francisco
MDW - SFO
MDWSFO
Chicago Midway
Tue 3/3
8:10 am-1:45 pm
1 stop7h 35m
San Francisco
Thu 3/5
11:25 pm-5:30 am
Nonstop4h 05m
$260
ChicagoSan Francisco
ORD - SFO
ORDSFO
Chicago O'Hare Intl
Tue 3/10
8:20 am-6:44 pm
2 stops12h 24m
San Francisco
Tue 3/17
4:21 pm-6:39 am
1 stop12h 18m
$261
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
MDW-SFO
ORD-SFO
PIA-SFO
MLI-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
MDW-SFO
ORD-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 February is currently the most expensive (average of $208). 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 10, 2026.
It’s optimal to fly from Illinois to San Francisco in the evening. By choosing this option you can save up to 28% 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 February 7, 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 10, 2026.
The most flights from USIL to SFO are scheduled on a Monday (58 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (3 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 locationsSanta Cruz
South San Francisco
Santa Clara
Roseville
Livermore
Watsonville
San Bruno
Daly City
Sunnyvale
Turlock
Vacaville
San Carlos
San Ramon
Redwood City
Rancho Cordova
San Lorenzo
Davis
Hollister
Manteca
Union City
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.
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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.
Complete your trip
Complete your trip to San Francisco by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Illinois to San Francisco by cabin class
Find flights from Illinois to San Francisco, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Illinois and San Francisco flights
Browse other Illinois and San Francisco flight options. Last updated on February 10, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to San Francisco
Explore flights to San Francisco departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on February 10, 2026.
Illinois to San Francisco flights
Consider these flights traveling from Illinois to San Francisco.
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 10, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$108 | Average$217 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$110 | Average$228 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$112 | Average$374 | FlexibilityNo cancel fee | On-time83% | |
| Cheapest$128 | Average$324 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$138 | Average$385 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$183 | Average$304 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$186 | Average$277 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$197 | Average$457 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$207 | Average$411 | FlexibilityNo cancel fee | On-time69% |