$70+ Cheap flights from San Diego (SAN) 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 5/11. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ORD
May 15 — May 221
Round-trip
1 adult, Economy
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Cheapest flights from San Diego to IllinoisExplore the most affordable flight options available from San Diego to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 15, 2026.
Explore the most affordable flight options available from San Diego to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 15, 2026.
This Mytrip deal was found by Cheapflights users on 4/15. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/86:25 am
SAN
- STL
1 stop10h 58m
Frontier
Tue 5/126:51 pm
STL
- SAN
1 stop28h 13m
Frontier
Deal found 4/15![Frontier logo]()
$160
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:34 pm
SAN
- STL
1 stop20h 32m
Frontier
Fri 5/89:18 pm
STL
- SAN
1 stop25h 51m
Frontier
Deal found 4/14![Frontier logo]()
$171
This Kiwi.com deal was found by Cheapflights users on 4/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/279:37 am
SAN
- STL
1 stop7h 46m
Frontier
Sat 5/308:08 pm
STL
- SAN
1 stop14h 34m
Frontier
Deal found 4/11![Frontier logo]()
$173
This Expedia deal was found by Cheapflights users on 4/13. 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 4/306:25 am
SAN
- STL
1 stop10h 56m
Frontier
Sat 5/98:08 pm
STL
- SAN
1 stop5h 42m
Frontier
Deal found 4/13![Frontier logo]()
$180
This Orbitz deal was found by Cheapflights users on 4/15. 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 5/2310:07 pm
SAN
- STL
1 stop20h 04m
Frontier
Mon 5/259:06 pm
STL
- SAN
1 stop26h 06m
Frontier
Deal found 4/15![Frontier logo]()
$190
This CheapOair deal was found by Cheapflights users on 4/15. 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 5/17:00 am
SAN
- STL
1 stop9h 16m
Frontier
Wed 5/66:51 pm
STL
- SAN
1 stop28h 18m
Frontier
Deal found 4/15![Frontier logo]()
$196
This Expedia deal was found by Cheapflights users on 4/14. 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.
Fri 5/2210:07 pm
SAN
- STL
1 stop17h 27m
Frontier
Mon 5/259:06 pm
STL
- SAN
1 stop26h 06m
Frontier
Deal found 4/14![Frontier logo]()
$205
This Frontier deal was found by Cheapflights users on 4/13. 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.
Fri 5/296:25 am
SAN
- STL
1 stop10h 58m
Frontier
Mon 6/18:08 pm
STL
- SAN
1 stop5h 42m
Frontier
Deal found 4/13![Frontier logo]()
$210
This CheapOair deal was found by Cheapflights users on 4/14. 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 5/16:25 am
SAN
- STL
1 stop10h 56m
Frontier
Sun 5/39:55 pm
STL
- SAN
1 stop22h 01m
Frontier
Deal found 4/14![Frontier logo]()
$211
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 5/124:17 pm
SAN
- STL
2 stops14h 38m
Frontier
Tue 5/196:51 pm
STL
- SAN
1 stop25h 48m
Frontier
Deal found 4/12![Frontier logo]()
$212
This Expedia deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:25 am
SAN
- ORD
1 stop12h 07m
Multiple Airlines
Sat 5/98:50 am
ORD
- SAN
Nonstop4h 40m
Multiple Airlines
Deal found 4/13![Multiple Airlines logo]()
$214
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 5/196:25 am
SAN
- ORD
1 stop27h 15m
Frontier
Sat 5/239:37 pm
ORD
- SAN
1 stop13h 05m
Frontier
Deal found 4/12![Frontier logo]()
$215
Best flights from San Diego to IllinoisDiscover carefully curated flight deals from San Diego to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 15, 2026.
Discover carefully curated flight deals from San Diego to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 15, 2026.
This Alaska Airlines deal was found by Cheapflights users on 4/14. 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 5/57:03 am
SAN
- ORD
Nonstop4h 10m
Alaska Airlines
Wed 5/68:50 am
ORD
- SAN
Nonstop4h 40m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$237
This United Airlines deal was found by Cheapflights users on 4/12. 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 5/2310:40 pm
SAN
- ORD
Nonstop4h 11m
United Airlines
Tue 5/267:00 am
ORD
- SAN
Nonstop4h 28m
United Airlines
Deal found 4/12![United Airlines logo]()
$237
This Southwest deal was found by Cheapflights users on 4/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/210:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Sat 5/96:10 pm
MDW
- SAN
Nonstop4h 20m
Southwest
Deal found 4/10![Southwest logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 4/13. 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 5/291:38 pm
SAN
- RFD
1 stop20h 33m
Multiple Airlines
Mon 6/19:13 pm
RFD
- SAN
1 stop20h 18m
Multiple Airlines
Deal found 4/13![Multiple Airlines logo]()
$241
This Delta deal was found by Cheapflights users on 4/15. 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 6/1810:17 pm
SAN
- MDW
1 stop8h 57m
Delta
Mon 6/227:16 pm
MDW
- SAN
1 stop6h 19m
Delta
Deal found 4/15![Delta logo]()
$277
This American Airlines deal was found by Cheapflights users on 4/14. 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.
Fri 5/153:09 pm
SAN
- MLI
1 stop6h 45m
American Airlines
Tue 5/1912:49 pm
MLI
- SAN
1 stop9h 54m
American Airlines
Deal found 4/14![American Airlines logo]()
$330
This Southwest deal was found by Cheapflights users on 4/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/96:25 am
SAN
- MDW
1 stop5h 55m
Southwest
Tue 5/196:45 am
MDW
- SAN
Nonstop4h 15m
Southwest
Deal found 4/10![Southwest logo]()
$243
This Alaska Airlines deal was found by Cheapflights users on 4/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/112:53 pm
SAN
- ORD
Nonstop4h 10m
Alaska Airlines
Sat 5/167:59 pm
ORD
- SAN
Nonstop4h 37m
Alaska Airlines
Deal found 4/10![Alaska Airlines logo]()
$267
This Southwest deal was found by Cheapflights users on 4/13. 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 5/98:10 am
SAN
- MDW
1 stop7h 40m
Southwest
Sat 5/166:15 am
MDW
- SAN
Nonstop4h 15m
Southwest
Deal found 4/13![Southwest logo]()
$247
This Kiwi.com deal was found by Cheapflights users on 4/10. 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.
Tue 7/144:17 pm
SAN
- RFD
1 stop25h 42m
Multiple Airlines
Wed 7/298:49 pm
RFD
- SAN
1 stop20h 43m
Multiple Airlines
Deal found 4/10![Multiple Airlines logo]()
$285
This Delta deal was found by Cheapflights users on 4/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1310:53 am
SAN
- MDW
1 stop8h 16m
Delta
Tue 5/199:22 am
MDW
- SAN
1 stop6h 58m
Delta
Deal found 4/11![Delta logo]()
$298
This Southwest deal was found by Cheapflights users on 4/13. 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 5/612:30 pm
SAN
- MDW
1 stop5h 25m
Southwest
Sat 5/912:45 pm
MDW
- SAN
1 stop5h 45m
Southwest
Deal found 4/13![Southwest logo]()
$257
This Alaska Airlines deal was found by Cheapflights users on 4/14. 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 5/297:00 am
SAN
- ORD
Nonstop4h 14m
Alaska Airlines
Mon 6/19:00 am
ORD
- SAN
Nonstop4h 37m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$297
This American Airlines deal was found by Cheapflights users on 4/12. 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 5/1912:51 pm
SAN
- MLI
2 stops9h 03m
American Airlines
Sun 5/246:51 pm
MLI
- SAN
1 stop6h 48m
American Airlines
Deal found 4/12![American Airlines logo]()
$335
This Southwest deal was found by Cheapflights users on 4/12. 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 5/278:40 am
SAN
- MDW
1 stop6h 30m
Southwest
Wed 6/32:15 pm
MDW
- SAN
1 stop6h 00m
Southwest
Deal found 4/12![Southwest logo]()
$257
This Kiwi.com deal was found by Cheapflights users on 4/10. 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 6/264:17 pm
SAN
- RFD
1 stop17h 57m
Multiple Airlines
Wed 7/18:49 pm
RFD
- SAN
1 stop20h 43m
Multiple Airlines
Deal found 4/10![Multiple Airlines logo]()
$315
This Delta deal was found by Cheapflights users on 4/14. 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 4/1810:30 pm
SAN
- MDW
1 stop9h 26m
Delta
Tue 4/219:29 am
MDW
- SAN
1 stop6h 06m
Delta
Deal found 4/14![Delta logo]()
$330
This United Airlines deal was found by Cheapflights users on 4/13. 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 9/1110:40 pm
SAN
- BMI
1 stop8h 17m
United Airlines
Fri 10/231:32 pm
BMI
- SAN
1 stop7h 05m
United Airlines
Deal found 4/13![United Airlines logo]()
$369
This Kiwi.com deal was found by Cheapflights users on 4/14. 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 4/222:12 pm
SAN
- RFD
1 stop19h 48m
Multiple Airlines
Mon 4/278:35 pm
RFD
- SAN
2 stops18h 42m
Multiple Airlines
Deal found 4/14![Multiple Airlines logo]()
$325
This Alaska Airlines deal was found by Cheapflights users on 4/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/17:35 pm
SAN
- ORD
1 stop9h 05m
Alaska Airlines
Fri 5/83:52 pm
ORD
- SAN
Nonstop4h 39m
Alaska Airlines
Deal found 4/10![Alaska Airlines logo]()
$327
This Southwest deal was found by Cheapflights users on 4/12. 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 5/272:40 pm
SAN
- ORD
1 stop7h 15m
Southwest
Wed 6/310:30 am
ORD
- SAN
2 stops9h 15m
Southwest
Deal found 4/12![Southwest logo]()
$272
This Delta deal was found by Cheapflights users on 4/15. 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 4/196:15 am
SAN
- MDW
1 stop9h 43m
Delta
Tue 4/2112:52 pm
MDW
- SAN
1 stop9h 59m
Delta
Deal found 4/15![Delta logo]()
$330
This American Airlines deal was found by Cheapflights users on 4/13. 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 4/301:16 pm
SAN
- MLI
2 stops8h 13m
American Airlines
Wed 5/612:04 pm
MLI
- SAN
2 stops8h 21m
American Airlines
Deal found 4/13![American Airlines logo]()
$366
This United Airlines deal was found by Cheapflights users on 4/14. 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 6/21:39 pm
SAN
- ORD
1 stop9h 20m
United Airlines
Fri 6/58:46 am
ORD
- SAN
Nonstop4h 35m
United Airlines
Deal found 4/14![United Airlines logo]()
$373
This Delta deal was found by Cheapflights users on 4/12. 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.
Tue 5/1912:41 pm
SAN
- MLI
1 stop7h 40m
Delta
Sun 5/2411:00 am
MLI
- SAN
1 stop10h 23m
Delta
Deal found 4/12![Delta logo]()
$330
This Southwest deal was found by Cheapflights users on 4/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/28:50 am
SAN
- ORD
2 stops11h 30m
Southwest
Sat 5/93:05 pm
ORD
- SAN
2 stops10h 20m
Southwest
Deal found 4/10![Southwest logo]()
$273
This Kiwi.com deal was found by Cheapflights users on 4/10. 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.
Tue 4/2112:29 pm
SAN
- RFD
1 stop23h 32m
Multiple Airlines
Wed 4/292:51 pm
RFD
- SAN
1 stop29h 38m
Multiple Airlines
Deal found 4/10![Multiple Airlines logo]()
$333
This American Airlines deal was found by Cheapflights users on 4/14. 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.
Fri 5/153:09 pm
SAN
- BMI
1 stop6h 43m
American Airlines
Mon 5/182:46 pm
BMI
- SAN
1 stop7h 57m
American Airlines
Deal found 4/14![American Airlines logo]()
$397
This United Airlines deal was found by Cheapflights users on 4/12. 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 5/57:15 am
SAN
- STL
2 stops11h 28m
United Airlines
Wed 5/66:00 am
STL
- SAN
1 stop7h 03m
United Airlines
Deal found 4/12![United Airlines logo]()
$402
This Alaska Airlines deal was found by Cheapflights users on 4/12. 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 5/51:00 pm
SAN
- STL
1 stop8h 59m
Alaska Airlines
Wed 5/67:00 am
STL
- SAN
1 stop8h 27m
Alaska Airlines
Deal found 4/12![Alaska Airlines logo]()
$367
Last-minute flights from San Diego to IllinoisDiscover last-minute flight deals from San Diego to Illinois. Data last updated April 15, 2026 and is based on user searches.
Discover last-minute flight deals from San Diego to Illinois. Data last updated April 15, 2026 and is based on user searches.
This Expedia deal was found by Cheapflights users on 4/13. 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 4/306:25 am
SAN
- STL
1 stop10h 56m
Frontier
Sat 5/98:08 pm
STL
- SAN
1 stop5h 42m
Frontier
Deal found 4/13![Frontier logo]()
$180
This CheapOair deal was found by Cheapflights users on 4/15. 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 5/17:00 am
SAN
- STL
1 stop9h 16m
Frontier
Wed 5/66:51 pm
STL
- SAN
1 stop28h 18m
Frontier
Deal found 4/15![Frontier logo]()
$196
This CheapOair deal was found by Cheapflights users on 4/14. 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 5/16:25 am
SAN
- STL
1 stop10h 56m
Frontier
Sun 5/39:55 pm
STL
- SAN
1 stop22h 01m
Frontier
Deal found 4/14![Frontier logo]()
$211
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:34 pm
SAN
- STL
1 stop20h 32m
Frontier
Fri 5/89:18 pm
STL
- SAN
1 stop25h 51m
Frontier
Deal found 4/14![Frontier logo]()
$171
This Expedia deal was found by Cheapflights users on 4/10. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:25 am
SAN
- ORD
1 stop12h 07m
Multiple Airlines
Sat 5/93:52 pm
ORD
- SAN
Nonstop4h 39m
Multiple Airlines
Deal found 4/10![Multiple Airlines logo]()
$214
This Expedia deal was found by Cheapflights users on 4/15. 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.
Fri 5/86:25 am
SAN
- STL
1 stop10h 58m
Frontier
Sat 5/98:08 pm
STL
- SAN
1 stop5h 42m
Frontier
Deal found 4/15![Frontier logo]()
$160
This Booking.com deal was found by Cheapflights users on 4/14. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/89:37 am
SAN
- STL
1 stop7h 46m
Frontier
Tue 5/126:51 pm
STL
- SAN
1 stop28h 13m
Frontier
Deal found 4/14![Frontier logo]()
$167
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 5/124:17 pm
SAN
- STL
2 stops14h 38m
Frontier
Tue 5/196:51 pm
STL
- SAN
1 stop25h 48m
Frontier
Deal found 4/12![Frontier logo]()
$212
This Expedia deal was found by Cheapflights users on 4/14. 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.
Fri 5/2210:07 pm
SAN
- STL
1 stop17h 27m
Frontier
Mon 5/259:06 pm
STL
- SAN
1 stop26h 06m
Frontier
Deal found 4/14![Frontier logo]()
$205
This Orbitz deal was found by Cheapflights users on 4/15. 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 5/2310:07 pm
SAN
- STL
1 stop20h 04m
Frontier
Mon 5/259:06 pm
STL
- SAN
1 stop26h 06m
Frontier
Deal found 4/15![Frontier logo]()
$190
This Kiwi.com deal was found by Cheapflights users on 4/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/279:37 am
SAN
- STL
1 stop7h 46m
Frontier
Sat 5/308:08 pm
STL
- SAN
1 stop14h 34m
Frontier
Deal found 4/11![Frontier logo]()
$173
This Frontier deal was found by Cheapflights users on 4/13. 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.
Fri 5/296:25 am
SAN
- STL
1 stop10h 58m
Frontier
Mon 6/18:08 pm
STL
- SAN
1 stop5h 42m
Frontier
Deal found 4/13![Frontier logo]()
$210
One-way flights from San Diego to IllinoisSearch for one-way flight options from San Diego to Illinois. Find affordable one-way fares based on user searches. Data last updated April 15, 2026.
Search for one-way flight options from San Diego to Illinois. Find affordable one-way fares based on user searches. Data last updated April 15, 2026.
This WAYA deal was found by Cheapflights users on 4/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WAYA is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/119:37 am
SAN
- STL
1 stop7h 46m
Frontier
Deal found 4/11![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 4/13. 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 5/96:25 am
SAN
- STL
1 stop10h 58m
Frontier
Deal found 4/13![Frontier logo]()
$72
This Frontier deal was found by Cheapflights users on 4/14. 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 5/106:25 am
SAN
- STL
1 stop6h 23m
Frontier
Deal found 4/14![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 4/13. 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 6/98:00 am
SAN
- STL
1 stop8h 24m
Frontier
Deal found 4/13![Frontier logo]()
$83
This Frontier deal was found by Cheapflights users on 4/14. 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 5/169:59 pm
SAN
- STL
1 stop11h 42m
Frontier
Deal found 4/14![Frontier logo]()
$86
This Trip.com deal was found by Cheapflights users on 4/14. 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 5/279:37 am
SAN
- STL
1 stop7h 46m
Frontier
Deal found 4/14![Frontier logo]()
$97
This Kiwi.com deal was found by Cheapflights users on 4/14. 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 6/158:29 pm
SAN
- STL
2 stops44h 54m
Frontier
Deal found 4/14![Frontier logo]()
$102
This Kiwi.com deal was found by Cheapflights users on 4/15. 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 6/176:25 am
SAN
- STL
1 stop10h 58m
Frontier
Deal found 4/15![Frontier logo]()
$104
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/156:25 am
SAN
- STL
1 stop6h 23m
Frontier
Deal found 4/14![Frontier logo]()
$105
This Super.com deal was found by Cheapflights users on 4/15. 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 4/292:12 pm
SAN
- STL
1 stop28h 48m
Frontier
Deal found 4/15![Frontier logo]()
$106
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 5/96:25 am
SAN
- ORD
1 stop12h 07m
Frontier
Deal found 4/12![Frontier logo]()
$110
This Frontier deal was found by Cheapflights users on 4/12. 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 6/106:25 am
SAN
- ORD
1 stop12h 18m
Frontier
Deal found 4/12![Frontier logo]()
$111
Find flight deals from San Diego to Illinois
Keep the following information in mind while searching for San Diego to Illinois flight deals. Data was last updated April 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $167 (Booking.com) |
One-way from | $70 (WAYA) |
Popular in | April |
Cheapest in | February |
Average price | $310 |
Good round-trip deal | $339 or less |
Good one-way deal | $209 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from San Diego 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 April 15, 2026.
Use the filters below to find and compare flights from San Diego to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
San DiegoChicago
SAN - ORD
SANORD
San Diego
Tue 5/5
7:03 am-1:13 pm
Nonstop4h 10m
Chicago O'Hare Intl
Wed 5/6
8:50 am-11:30 am
Nonstop4h 40m
$237
San DiegoChicago
SAN - ORD
SANORD
San Diego
Sat 5/23
10:40 pm-4:51 am
Nonstop4h 11m
Chicago O'Hare Intl
Tue 5/26
7:00 am-9:28 am
Nonstop4h 28m
$237
Quickest round-trip
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Sat 5/2
10:40 pm-4:35 am
Nonstop3h 55m
Chicago Midway
Sat 5/9
6:10 pm-8:30 pm
Nonstop4h 20m
$237
San DiegoChicago
SAN - RFD
SANRFD
San Diego
Fri 5/29
1:38 pm-12:11 pm
1 stop20h 33m
Chicago Greater Rockford
Mon 6/1
9:13 pm-3:31 pm
1 stop20h 18m
$241
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Sat 5/9
6:25 am-2:20 pm
1 stop5h 55m
Chicago Midway
Tue 5/19
6:45 am-9:00 am
Nonstop4h 15m
$243
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Sat 5/9
8:10 am-5:50 pm
1 stop7h 40m
Chicago Midway
Sat 5/16
6:15 am-8:30 am
Nonstop4h 15m
$247
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Wed 5/6
12:30 pm-7:55 pm
1 stop5h 25m
Chicago Midway
Sat 5/9
12:45 pm-4:30 pm
1 stop5h 45m
$257
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Wed 5/27
8:40 am-5:10 pm
1 stop6h 30m
Chicago Midway
Wed 6/3
2:15 pm-6:15 pm
1 stop6h 00m
$257
San DiegoChicago
SAN - ORD
SANORD
San Diego
Fri 5/1
12:53 pm-7:03 pm
Nonstop4h 10m
Chicago O'Hare Intl
Sat 5/16
7:59 pm-10:36 pm
Nonstop4h 37m
$267
San DiegoChicago
SAN - ORD
SANORD
San Diego
Wed 5/27
2:40 pm-11:55 pm
1 stop7h 15m
Chicago O'Hare Intl
Wed 6/3
10:30 am-5:45 pm
2 stops9h 15m
$272
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from San Diego to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from San Diego with our price prediction graph.
SAN-STL
SAN-ORD
SAN-MDW
SAN-RFD
SAN-MLI
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 Diego to Illinois
SAN-USIL
SAN-STL
SAN-ORD
SAN-MDW
SAN-RFD
What is the cheapest month to book a flight from San Diego to Illinois?
Currently, April is the cheapest month in which you can book a flight from San Diego to Illinois (average of $96). Flying from San Diego to Illinois in March is currently the most expensive (average of $162). 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 SAN to IL?
Find hourly flight availability from San Diego 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 April 15, 2026.
When flying from San Diego to Illinois, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 34% versus a flight in the morning.
What is the cheapest day to fly from San Diego to Illinois?
Use this chart to determine the cheapest time to fly round-trip from San Diego to Illinois. Price data was last updated on April 11, 2026.
Travelers seeking maximum savings on their San Diego to Illinois flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Saturday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Weekly flight availability from San Diego to Illinois
Explore weekly flight availability from San Diego 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 April 15, 2026.
The most flights from SAN to USIL are scheduled on a Monday (45 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (35 on average).
How much does it cost to fly round-trip from San Diego to Illinois?
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 April 15, 2026.
Read reviews from past customers who have flown Southwest,Alaska Airlines, andUnited Airlines from San Diego to Illinois. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Comfort
8.0
Crew
8.6
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 Diego 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 Diego 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 Diego to Illinois by cabin class
Find flights from San Diego to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
San Diego and Illinois flights
Browse other San Diego and Illinois flight options. Last updated on April 15, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
San Diego to Illinois flights
Consider these flights traveling from San Diego to Illinois.
Top 7 airlines flying from San Diego to Illinois
Discover the top 7 airlines that operate flights from San Diego 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 April 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$92 | Average$221 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$109 | Average$214 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$139 | Average$197 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$145 | Average$280 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$157 | Average$443 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$166 | Average$445 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$205 | Average$340 | FlexibilityNo cancel fee | On-time63% |