$79+ 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 5/19. Fares are subject to change and may not be available on all flights or dates of travel.
SFO — ORD
Apr 20 — Apr 271
Round-trip
1 adult, Economy
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Find cheap flights from San Francisco to Illinois with Cheapflights
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Cheapest flights from San Francisco to IllinoisExplore 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 March 21, 2026.
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 March 21, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/306:29 pm
SFO
- ORD
1 stop9h 51m
Frontier
Sat 5/210:23 am
ORD
- SFO
2 stops15h 02m
Frontier
Deal found 3/16![Frontier logo]()
$243
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/58:48 pm
SFO
- ORD
1 stop7h 51m
Multiple Airlines
Mon 5/185:15 am
ORD
- SFO
1 stop17h 49m
Multiple Airlines
Deal found 3/16![Multiple Airlines logo]()
$246
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/155:25 am
SFO
- MDW
Nonstop4h 10m
Southwest
Wed 4/225:15 pm
MDW
- SFO
1 stop6h 50m
Southwest
Deal found 3/16![Southwest logo]()
$247
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/27:40 pm
SFO
- ORD
1 stop8h 28m
Multiple Airlines
Thu 5/73:52 pm
ORD
- SFO
1 stop9h 09m
Multiple Airlines
Deal found 3/16![Multiple Airlines logo]()
$247
This Kiwi.com deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/168:48 pm
SFO
- ORD
1 stop7h 51m
Frontier
Mon 5/189:42 pm
ORD
- SFO
1 stop16h 00m
Frontier
Deal found 3/21![Frontier logo]()
$248
This Cheapflightsfares deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1711:16 pm
SFO
- ORD
1 stop12h 51m
Frontier
Sun 5/37:21 pm
ORD
- SFO
1 stop28h 18m
Frontier
Deal found 3/17![Frontier logo]()
$249
This Frontier deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2811:59 pm
SFO
- MDW
1 stop12h 13m
Frontier
Sun 5/316:00 am
MDW
- SFO
1 stop15h 34m
Frontier
Deal found 3/17![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/238:56 am
SFO
- ORD
1 stop9h 41m
Frontier
Thu 5/286:55 am
ORD
- SFO
1 stop14h 39m
Frontier
Deal found 3/19![Frontier logo]()
$250
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1311:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Tue 4/219:00 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Deal found 3/17![Southwest logo]()
$251
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/22:00 pm
SFO
- ORD
Nonstop4h 39m
United Airlines
Tue 5/59:51 pm
ORD
- SFO
Nonstop4h 59m
United Airlines
Deal found 3/17![United Airlines logo]()
$251
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/1411:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Tue 4/214:00 pm
MDW
- SFO
2 stops9h 15m
Southwest
Deal found 3/17![Southwest logo]()
$252
This Kiwi.com deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:40 pm
SFO
- ORD
1 stop8h 28m
Multiple Airlines
Thu 4/169:44 pm
ORD
- SFO
2 stops25h 29m
Multiple Airlines
Deal found 3/21![Multiple Airlines logo]()
$252
Best flights from San Francisco to IllinoisDiscover carefully curated flight deals from San Francisco to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 21, 2026.
Discover carefully curated flight deals from San Francisco to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 21, 2026.
This Southwest deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/65:25 am
SFO
- MDW
Nonstop4h 10m
Southwest
Sat 5/96:10 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Deal found 3/19![Southwest logo]()
$251
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2912:45 am
SFO
- ORD
Nonstop4h 22m
United Airlines
Sat 5/22:24 pm
ORD
- SFO
Nonstop4h 57m
United Airlines
Deal found 3/17![United Airlines logo]()
$265
This Delta deal was found by Cheapflights users on 3/18. 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 4/2210:55 pm
SFO
- ORD
1 stop9h 24m
Delta
Sat 4/256:25 am
ORD
- SFO
1 stop7h 00m
Delta
Deal found 3/18![Delta logo]()
$271
This American Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/95:14 am
SFO
- BMI
1 stop8h 01m
American Airlines
Wed 5/135:00 am
BMI
- SFO
1 stop6h 52m
American Airlines
Deal found 3/16![American Airlines logo]()
$349
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/99:58 pm
SFO
- RFD
1 stop20h 36m
Multiple Airlines
Thu 8/131:24 pm
RFD
- SFO
1 stop7h 01m
Multiple Airlines
Deal found 3/17![Multiple Airlines logo]()
$369
This Expedia deal was found by Cheapflights users on 3/18. 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 5/78:45 am
SFO
- MLI
2 stops13h 09m
Alaska Airlines
Tue 5/1212:49 pm
MLI
- SFO
2 stops12h 12m
Alaska Airlines
Deal found 3/18![Alaska Airlines logo]()
$449
This Southwest deal was found by Cheapflights users on 3/18. 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 4/2811:25 am
SFO
- ORD
2 stops10h 30m
Southwest
Tue 5/57:45 am
ORD
- SFO
2 stops12h 45m
Southwest
Deal found 3/18![Southwest logo]()
$273
This Delta deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1611:59 pm
SFO
- ORD
1 stop6h 39m
Delta
Sat 4/187:00 am
ORD
- SFO
1 stop9h 55m
Delta
Deal found 3/20![Delta logo]()
$285
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/115:15 am
SFO
- MDW
Nonstop4h 10m
Southwest
Thu 5/147:40 pm
MDW
- SFO
1 stop6h 30m
Southwest
Deal found 3/16![Southwest logo]()
$275
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1611:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Sat 4/256:45 am
MDW
- SFO
1 stop7h 50m
Southwest
Deal found 3/17![Southwest logo]()
$275
This Delta deal was found by Cheapflights users on 3/18. 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 5/2012:15 am
SFO
- MDW
1 stop6h 27m
Delta
Wed 5/277:13 pm
MDW
- SFO
1 stop6h 37m
Delta
Deal found 3/18![Delta logo]()
$306
This United Airlines deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Tue 4/283:45 pm
ORD
- SFO
Nonstop4h 53m
United Airlines
Deal found 3/19![United Airlines logo]()
$337
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/299:00 pm
SFO
- RFD
1 stop13h 24m
Multiple Airlines
Wed 8/58:58 pm
RFD
- SFO
1 stop26h 06m
Multiple Airlines
Deal found 3/16![Multiple Airlines logo]()
$370
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/166:20 am
SFO
- MDW
2 stops9h 35m
Southwest
Thu 4/239:45 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Deal found 3/17![Southwest logo]()
$280
This American Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/3111:29 pm
SFO
- CMI
1 stop7h 53m
American Airlines
Sat 4/46:00 am
CMI
- SFO
1 stop8h 56m
American Airlines
Deal found 3/16![American Airlines logo]()
$388
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/1712:45 am
SFO
- ORD
Nonstop4h 22m
United Airlines
Sat 5/236:10 am
ORD
- SFO
Nonstop4h 37m
United Airlines
Deal found 3/17![United Airlines logo]()
$355
This Kiwi.com deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/811:24 am
SFO
- RFD
1 stop23h 00m
Multiple Airlines
Fri 7/179:13 pm
RFD
- SFO
1 stop21h 03m
Multiple Airlines
Deal found 3/19![Multiple Airlines logo]()
$371
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1311:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Thu 4/164:05 pm
MDW
- SFO
2 stops9h 00m
Southwest
Deal found 3/17![Southwest logo]()
$280
This Delta deal was found by Cheapflights users on 3/18. 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 5/612:20 am
SFO
- MDW
1 stop6h 22m
Delta
Sun 5/107:13 pm
MDW
- SFO
1 stop6h 37m
Delta
Deal found 3/18![Delta logo]()
$356
This United Airlines deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1311:52 pm
SFO
- MLI
1 stop8h 06m
United Airlines
Tue 4/217:34 pm
MLI
- SFO
1 stop7h 05m
United Airlines
Deal found 3/20![United Airlines logo]()
$369
This Southwest deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/611:25 am
SFO
- ORD
2 stops10h 30m
Southwest
Sat 5/97:00 am
ORD
- SFO
2 stops11h 10m
Southwest
Deal found 3/19![Southwest logo]()
$281
This American Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/222:57 pm
SFO
- EVV
1 stop6h 57m
American Airlines
Tue 4/284:03 pm
EVV
- SFO
1 stop9h 06m
American Airlines
Deal found 3/16![American Airlines logo]()
$419
This Delta deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1011:45 pm
SFO
- MDW
1 stop6h 57m
Delta
Mon 7/131:00 pm
MDW
- SFO
1 stop9h 22m
Delta
Deal found 3/20![Delta logo]()
$364
This Alaska Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/266:00 am
SFO
- STL
1 stop7h 16m
Alaska Airlines
Tue 6/167:56 pm
STL
- SFO
2 stops15h 24m
Alaska Airlines
Deal found 3/17![Alaska Airlines logo]()
$485
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/912:55 am
SFO
- ORD
Nonstop4h 21m
United Airlines
Sun 9/137:40 am
ORD
- SFO
Nonstop4h 46m
United Airlines
Deal found 3/17![United Airlines logo]()
$371
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/129:58 pm
SFO
- RFD
1 stop12h 16m
Multiple Airlines
Sun 6/141:13 pm
RFD
- SFO
1 stop20h 30m
Multiple Airlines
Deal found 3/17![Multiple Airlines logo]()
$410
This American Airlines deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/610:13 am
SFO
- BMI
2 stops10h 14m
American Airlines
Wed 5/1311:16 am
BMI
- SFO
2 stops9h 48m
American Airlines
Deal found 3/16![American Airlines logo]()
$445
This Delta deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/3111:45 pm
SFO
- BMI
1 stop9h 26m
Delta
Mon 8/104:00 pm
BMI
- SFO
1 stop8h 39m
Delta
Deal found 3/16![Delta logo]()
$369
This Kiwi.com deal was found by Cheapflights users on 3/18. 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 5/2710:40 pm
SFO
- RFD
1 stop11h 41m
Multiple Airlines
Mon 6/19:13 pm
RFD
- SFO
1 stop21h 17m
Multiple Airlines
Deal found 3/18![Multiple Airlines logo]()
$411
This Southwest deal was found by Cheapflights users on 3/18. 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 4/1811:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Fri 4/243:30 pm
MDW
- SFO
1 stop6h 30m
Southwest
Deal found 3/18![Southwest logo]()
$319
Last-minute flights from San Francisco to IllinoisDiscover last-minute flight deals from San Francisco to Illinois. Data last updated March 21, 2026 and is based on user searches.
Discover last-minute flight deals from San Francisco to Illinois. Data last updated March 21, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/610:03 pm
SFO
- ORD
1 stop10h 41m
Frontier
Fri 4/1710:55 am
ORD
- SFO
1 stop15h 32m
Frontier
Deal found 3/17![Frontier logo]()
$247
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/76:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Wed 4/86:25 am
ORD
- SFO
Nonstop4h 51m
United Airlines
Deal found 3/17![United Airlines logo]()
$254
This Cheapflightsfares deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/910:57 pm
SFO
- ORD
1 stop10h 53m
Frontier
Wed 4/228:58 pm
ORD
- SFO
1 stop13h 25m
Frontier
Deal found 3/21![Frontier logo]()
$250
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1311:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Tue 4/219:00 pm
MDW
- SFO
Nonstop4h 35m
Southwest
Deal found 3/17![Southwest logo]()
$251
This Kiwi.com deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/133:10 pm
SFO
- ORD
2 stops20h 57m
Frontier
Sat 4/185:50 am
ORD
- SFO
1 stop13h 44m
Frontier
Deal found 3/21![Frontier logo]()
$253
This Southwest deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/1411:25 pm
SFO
- MDW
Nonstop4h 15m
Southwest
Tue 4/214:00 pm
MDW
- SFO
2 stops9h 15m
Southwest
Deal found 3/17![Southwest logo]()
$252
This Kiwi.com deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:40 pm
SFO
- ORD
1 stop8h 28m
Multiple Airlines
Thu 4/169:44 pm
ORD
- SFO
2 stops25h 29m
Multiple Airlines
Deal found 3/21![Multiple Airlines logo]()
$252
This Southwest deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/155:25 am
SFO
- MDW
Nonstop4h 10m
Southwest
Wed 4/225:15 pm
MDW
- SFO
1 stop6h 50m
Southwest
Deal found 3/16![Southwest logo]()
$247
This United Airlines deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/156:29 pm
SFO
- ORD
Nonstop4h 30m
United Airlines
Sat 4/183:45 pm
ORD
- SFO
Nonstop4h 53m
United Airlines
Deal found 3/17![United Airlines logo]()
$251
This Cheapflightsfares deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1711:16 pm
SFO
- ORD
1 stop12h 51m
Frontier
Sun 5/37:21 pm
ORD
- SFO
1 stop28h 18m
Frontier
Deal found 3/17![Frontier logo]()
$249
This Frontier deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/2311:16 pm
SFO
- MDW
1 stop11h 14m
Frontier
Tue 4/286:10 am
MDW
- SFO
1 stop13h 24m
Frontier
Deal found 3/17![Frontier logo]()
$250
This Kiwi.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/306:29 pm
SFO
- ORD
1 stop9h 51m
Frontier
Sat 5/210:23 am
ORD
- SFO
2 stops15h 02m
Frontier
Deal found 3/16![Frontier logo]()
$243
One-way flights from San Francisco to IllinoisSearch for one-way flight options from San Francisco to Illinois. Find affordable one-way fares based on user searches. Data last updated March 21, 2026.
Search for one-way flight options from San Francisco to Illinois. Find affordable one-way fares based on user searches. Data last updated March 21, 2026.
This Super.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/1910:15 pm
SFO
- STL
1 stop8h 40m
Frontier
Deal found 3/20![Frontier logo]()
$79
This Super.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/126:00 am
SFO
- STL
1 stop25h 48m
Frontier
Deal found 3/20![Frontier logo]()
$85
This Expedia deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1110:40 pm
SFO
- STL
1 stop17h 26m
Frontier
Deal found 3/20![Frontier logo]()
$86
This Super.com deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/1210:15 pm
SFO
- STL
1 stop8h 40m
Frontier
Deal found 3/21![Frontier logo]()
$89
This CheapOair deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/46:13 pm
SFO
- STL
1 stop21h 53m
Frontier
Deal found 3/20![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/911:20 am
SFO
- STL
1 stop22h 07m
Frontier
Deal found 3/20![Frontier logo]()
$104
This Frontier deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/1710:15 pm
SFO
- STL
1 stop8h 40m
Frontier
Deal found 3/20![Frontier logo]()
$105
This Super.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/511:59 pm
SFO
- MDW
1 stop12h 13m
Frontier
Deal found 3/16![Frontier logo]()
$109
This Super.com deal was found by Cheapflights users on 3/18. 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 4/292:47 pm
SFO
- STL
1 stop28h 13m
Frontier
Deal found 3/18![Frontier logo]()
$109
This Super.com deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2811:59 pm
SFO
- MDW
1 stop12h 13m
Frontier
Deal found 3/16![Frontier logo]()
$110
This Super.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/176:00 am
SFO
- STL
1 stop11h 21m
Frontier
Deal found 3/20![Frontier logo]()
$110
This Cheapflightsfares deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1711:16 pm
SFO
- ORD
1 stop12h 51m
Frontier
Deal found 3/17![Frontier logo]()
$110
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 March 21, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $243 (Kiwi.com) |
One-way from | $79 (Super.com) |
Popular in | November |
Cheapest in | September |
Average price | $427 |
Good round-trip deal | $337 or less |
Good one-way deal | $193 or less |
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 March 21, 2026.
Use the filters below to find and compare flights from San Francisco to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
San FranciscoChicago
SFO - MDW
SFOMDW
San Francisco
Wed 5/6
5:25 am-11:35 am
Nonstop4h 10m
Chicago Midway
Sat 5/9
6:10 pm-8:45 pm
Nonstop4h 35m
$251
San FranciscoChicago
SFO - ORD
SFOORD
San Francisco
Wed 4/29
12:45 am-7:07 am
Nonstop4h 22m
Chicago O'Hare Intl
Sat 5/2
2:24 pm-5:21 pm
Nonstop4h 57m
$265
San FranciscoChicago
SFO - ORD
SFOORD
San Francisco
Wed 4/22
10:55 pm-10:19 am
1 stop9h 24m
Chicago O'Hare Intl
Sat 4/25
6:25 am-11:25 am
1 stop7h 00m
$271
San FranciscoChicago
SFO - ORD
SFOORD
San Francisco
Tue 4/28
11:25 am-11:55 pm
2 stops10h 30m
Chicago O'Hare Intl
Tue 5/5
7:45 am-6:30 pm
2 stops12h 45m
$273
San FranciscoChicago
SFO - MDW
SFOMDW
San Francisco
Mon 5/11
5:15 am-11:25 am
Nonstop4h 10m
Chicago Midway
Thu 5/14
7:40 pm-12:10 am
1 stop6h 30m
$275
San FranciscoChicago
SFO - MDW
SFOMDW
San Francisco
Thu 4/16
11:25 pm-5:40 am
Nonstop4h 15m
Chicago Midway
Sat 4/25
6:45 am-12:35 pm
1 stop7h 50m
$275
San FranciscoChicago
SFO - MDW
SFOMDW
San Francisco
Thu 4/16
6:20 am-5:55 pm
2 stops9h 35m
Chicago Midway
Thu 4/23
9:45 pm-12:20 am
Nonstop4h 35m
$280
San FranciscoChicago
SFO - MDW
SFOMDW
San Francisco
Mon 4/13
11:25 pm-5:40 am
Nonstop4h 15m
Chicago Midway
Thu 4/16
4:05 pm-11:05 pm
2 stops9h 00m
$280
San FranciscoChicago
SFO - ORD
SFOORD
San Francisco
Wed 5/6
11:25 am-11:55 pm
2 stops10h 30m
Chicago O'Hare Intl
Sat 5/9
7:00 am-4:10 pm
2 stops11h 10m
$281
San FranciscoChicago
SFO - ORD
SFOORD
San Francisco
Thu 4/16
11:59 pm-8:38 am
1 stop6h 39m
Chicago O'Hare Intl
Sat 4/18
7:00 am-2:55 pm
1 stop9h 55m
$285
Showing 1-10 of 60 resultsSorted by cheapest first
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.
SFO-MDW
SFO-ORD
SFO-RFD
SFO-BMI
SFO-STL
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
SFO-USIL
SFO-MDW
SFO-ORD
SFO-RFD
SFO-BMI
What is the cheapest month to book a flight from San Francisco to Illinois?
Currently, April is the cheapest month in which you can book a flight from San Francisco to Illinois (average of $115). Flying from San Francisco to Illinois in December is currently the most expensive (average of $233). 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 March 21, 2026.
It’s optimal to fly from San Francisco to Illinois in the afternoon. By choosing this option you can save up to 30% on the cost of your flight, compared to a flight at noon.
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 March 14, 2026.
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. Sunday 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 March 21, 2026.
The most flights from SFO to USIL are scheduled on a Friday (75 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (45 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 March 21, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andUnited 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.
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
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.
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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.
Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from San Francisco to Illinois by cabin class
Find flights from San Francisco to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
San Francisco and Illinois flights
Browse other San Francisco and Illinois flight options. Last updated on March 21, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
San Francisco to Illinois flights
Consider these flights traveling from San Francisco to Illinois.
Top 8 airlines flying from San Francisco to Illinois
Discover the top 8 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 March 21, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$101 | Average$258 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$118 | Average$256 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$128 | Average$341 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$133 | Average$471 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$185 | Average$354 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$186 | Average$313 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$197 | Average$498 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$234 | Average$316 | FlexibilityNo cancel fee | On-time62% |