$67+ 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 3/17. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ORD
Mar 25 — Apr 11
1 adult, Economy
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Find cheap flights from San Diego to Illinois with Cheapflights
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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 February 23, 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 February 23, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 3/318:25 am
SAN
- STL
1 stop23h 23m
Frontier
Fri 4/38:16 pm
STL
- SAN
1 stop29h 46m
Frontier
Deal found 2/21![Frontier logo]()
$139
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/96:25 am
SAN
- STL
1 stop25h 23m
Frontier
Mon 4/138:19 pm
STL
- SAN
1 stop25h 45m
Frontier
Deal found 2/20![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 4/59:28 pm
SAN
- STL
1 stop10h 20m
Frontier
Sat 4/118:16 pm
STL
- SAN
1 stop29h 46m
Frontier
Deal found 2/22![Frontier logo]()
$154
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 3/2310:13 pm
SAN
- STL
2 stops33h 36m
Frontier
Mon 3/308:12 pm
STL
- SAN
1 stop27h 02m
Frontier
Deal found 2/21![Frontier logo]()
$162
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/172:08 pm
SAN
- ORD
1 stop14h 00m
Frontier
Tue 3/248:55 pm
ORD
- SAN
1 stop18h 18m
Frontier
Deal found 2/20![Frontier logo]()
$163
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 5/49:00 pm
SAN
- ORD
1 stop7h 47m
Frontier
Mon 5/119:18 pm
ORD
- SAN
1 stop18h 34m
Frontier
Deal found 2/22![Frontier logo]()
$164
This Kiwi.com deal was found by Cheapflights users on 2/19. 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 4/298:00 am
SAN
- ORD
2 stops23h 10m
Multiple Airlines
Wed 5/65:09 pm
ORD
- SAN
1 stop26h 31m
Multiple Airlines
Deal found 2/19![Multiple Airlines logo]()
$165
This United Airlines deal was found by Cheapflights users on 2/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/64:04 pm
SAN
- ORD
1 stop6h 54m
United Airlines
Sat 5/97:05 am
ORD
- SAN
Nonstop4h 37m
United Airlines
Deal found 2/21![United Airlines logo]()
$166
This Alaska Airlines deal was found by Cheapflights users on 2/19. 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 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
Sat 5/98:50 am
ORD
- SAN
Nonstop4h 40m
Alaska Airlines
Deal found 2/19![Alaska Airlines logo]()
$167
This Southwest deal was found by Cheapflights users on 2/19. 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 5/610:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Mon 5/116:35 am
MDW
- SAN
Nonstop4h 15m
Southwest
Deal found 2/19![Southwest logo]()
$167
This American Airlines deal was found by Cheapflights users on 2/20. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2210:40 pm
SAN
- ORD
Nonstop4h 05m
American Airlines
Sun 4/269:00 pm
ORD
- SAN
Nonstop4h 33m
American Airlines
Deal found 2/20![American Airlines logo]()
$168
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 3/169:00 am
SAN
- ORD
1 stop13h 57m
Multiple Airlines
Tue 3/244:36 pm
ORD
- SAN
2 stops22h 37m
Multiple Airlines
Deal found 2/22![Multiple Airlines logo]()
$169
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 February 23, 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 February 23, 2026.
This Southwest deal was found by Cheapflights users on 2/18. 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.
Wed 3/186:30 am
SAN
- MDW
Nonstop4h 05m
Southwest
Mon 3/238:55 pm
MDW
- SAN
Nonstop4h 30m
Southwest
Deal found 2/18![Southwest logo]()
$177
This United Airlines deal was found by Cheapflights users on 2/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1510:30 pm
SAN
- ORD
Nonstop4h 05m
United Airlines
Mon 4/206:00 pm
ORD
- SAN
1 stop7h 59m
United Airlines
Deal found 2/18![United Airlines logo]()
$187
This Alaska Airlines deal was found by Cheapflights users on 2/18. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/197:55 am
SAN
- ORD
Nonstop4h 26m
Alaska Airlines
Mon 3/237:59 pm
ORD
- SAN
Nonstop4h 42m
Alaska Airlines
Deal found 2/18![Alaska Airlines logo]()
$197
This Kiwi.com deal was found by Cheapflights users on 2/19. 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.
Thu 4/307:23 pm
SAN
- RFD
1 stop22h 22m
Multiple Airlines
Mon 5/48:35 pm
RFD
- SAN
1 stop16h 59m
Multiple Airlines
Deal found 2/19![Multiple Airlines logo]()
$202
This Kiwi.com deal was found by Cheapflights users on 2/18. 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 4/1512:29 pm
SAN
- MDW
1 stop24h 35m
Frontier
Mon 4/204:14 pm
MDW
- SAN
1 stop9h 27m
Frontier
Deal found 2/18![Frontier logo]()
$212
This Delta deal was found by Cheapflights users on 2/20. 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 4/236:15 am
SAN
- ORD
1 stop8h 03m
Delta
Sun 4/266:25 am
ORD
- SAN
1 stop6h 18m
Delta
Deal found 2/20![Delta logo]()
$237
This American Airlines deal was found by Cheapflights users on 2/19. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:17 pm
SAN
- STL
1 stop8h 42m
American Airlines
Sat 4/252:12 pm
STL
- SAN
1 stop8h 38m
American Airlines
Deal found 2/19![American Airlines logo]()
$237
This Southwest deal was found by Cheapflights users on 2/19. 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.
Sat 4/1810:40 pm
SAN
- MDW
1 stop6h 10m
Southwest
Wed 4/226:45 am
MDW
- SAN
Nonstop4h 15m
Southwest
Deal found 2/19![Southwest logo]()
$187
This Alaska Airlines deal was found by Cheapflights users on 2/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/912:37 pm
SAN
- ORD
Nonstop4h 25m
Alaska Airlines
Mon 4/137:59 pm
ORD
- SAN
Nonstop4h 42m
Alaska Airlines
Deal found 2/19![Alaska Airlines logo]()
$197
This United Airlines deal was found by Cheapflights users on 2/20. 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.
Wed 4/812:40 pm
SAN
- ORD
1 stop6h 40m
United Airlines
Sun 4/127:00 am
ORD
- SAN
Nonstop4h 40m
United Airlines
Deal found 2/20![United Airlines logo]()
$207
This Alaska Airlines deal was found by Cheapflights users on 2/18. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/178:26 pm
SAN
- ORD
1 stop8h 13m
Alaska Airlines
Tue 3/248:20 am
ORD
- SAN
Nonstop4h 42m
Alaska Airlines
Deal found 2/18![Alaska Airlines logo]()
$207
This Kiwi.com deal was found by Cheapflights users on 2/19. 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 4/1510:30 am
SAN
- STL
2 stops22h 00m
Frontier
Sun 4/199:55 pm
STL
- SAN
1 stop22h 01m
Frontier
Deal found 2/19![Frontier logo]()
$228
This Delta deal was found by Cheapflights users on 2/20. 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 3/1310:30 pm
SAN
- ORD
1 stop8h 00m
Delta
Mon 3/165:40 pm
ORD
- SAN
1 stop7h 19m
Delta
Deal found 2/20![Delta logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/1612:40 pm
SAN
- ORD
1 stop6h 43m
United Airlines
Mon 5/187:05 am
ORD
- SAN
Nonstop4h 37m
United Airlines
Deal found 2/21![United Airlines logo]()
$227
This Alaska Airlines deal was found by Cheapflights users on 2/21. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/307:03 am
SAN
- ORD
Nonstop4h 10m
Alaska Airlines
Wed 5/68:50 am
ORD
- SAN
Nonstop4h 40m
Alaska Airlines
Deal found 2/21![Alaska Airlines logo]()
$207
This Southwest deal was found by Cheapflights users on 2/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/174:20 pm
SAN
- MDW
1 stop5h 50m
Southwest
Tue 3/2410:30 am
MDW
- SAN
1 stop7h 20m
Southwest
Deal found 2/20![Southwest logo]()
$229
This Delta deal was found by Cheapflights users on 2/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/159:55 pm
SAN
- ORD
1 stop8h 35m
Delta
Tue 3/177:10 pm
ORD
- SAN
1 stop6h 38m
Delta
Deal found 2/19![Delta logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 2/19. 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.
Mon 3/309:58 pm
SAN
- STL
2 stops33h 50m
Frontier
Fri 4/248:06 pm
STL
- SAN
1 stop29h 00m
Frontier
Deal found 2/19![Frontier logo]()
$238
This United Airlines deal was found by Cheapflights users on 2/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/185:00 pm
SAN
- ORD
Nonstop3h 59m
United Airlines
Tue 3/247:05 am
ORD
- SAN
Nonstop4h 42m
United Airlines
Deal found 2/18![United Airlines logo]()
$227
This Southwest deal was found by Cheapflights users on 2/18. 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.
Thu 5/2110:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Sun 5/245:40 pm
MDW
- SAN
Nonstop4h 20m
Southwest
Deal found 2/18![Southwest logo]()
$232
This Delta deal was found by Cheapflights users on 2/18. 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.
Thu 4/910:10 pm
SAN
- MDW
1 stop8h 43m
Delta
Mon 4/132:12 pm
MDW
- SAN
1 stop8h 30m
Delta
Deal found 2/18![Delta logo]()
$237
This Alaska Airlines deal was found by Cheapflights users on 2/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/812:37 pm
SAN
- ORD
Nonstop4h 25m
Alaska Airlines
Fri 4/107:59 pm
ORD
- SAN
Nonstop4h 42m
Alaska Airlines
Deal found 2/19![Alaska Airlines logo]()
$222
This Delta deal was found by Cheapflights users on 2/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/110:10 pm
SAN
- MDW
1 stop8h 37m
Delta
Tue 5/59:29 am
MDW
- SAN
1 stop6h 06m
Delta
Deal found 2/21![Delta logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 2/19. 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.
Sat 4/112:53 pm
SAN
- MLI
1 stop18h 36m
Multiple Airlines
Mon 4/139:55 pm
MLI
- SAN
1 stop15h 39m
Multiple Airlines
Deal found 2/19![Multiple Airlines logo]()
$316
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 3/69:18 pm
SAN
- STL
1 stop10h 31m
Frontier
Sun 3/810:47 pm
STL
- SAN
1 stop18h 57m
Frontier
Deal found 2/22![Frontier logo]()
$277
This Delta deal was found by Cheapflights users on 2/18. 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.
Tue 3/1710:10 pm
SAN
- MDW
1 stop8h 43m
Delta
Tue 3/247:20 pm
MDW
- SAN
1 stop6h 20m
Delta
Deal found 2/18![Delta logo]()
$237
This United Airlines deal was found by Cheapflights users on 2/19. 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.
Tue 3/311:05 am
SAN
- STL
2 stops7h 21m
United Airlines
Wed 3/48:41 am
STL
- SAN
1 stop8h 19m
United Airlines
Deal found 2/19![United Airlines logo]()
$282
This American Airlines deal was found by Cheapflights users on 2/19. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/251:34 pm
SAN
- EVV
1 stop8h 12m
American Airlines
Tue 3/317:06 am
EVV
- SAN
1 stop7h 35m
American Airlines
Deal found 2/19![American Airlines logo]()
$379
This Delta deal was found by Cheapflights users on 2/18. 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 3/1810:10 pm
SAN
- MDW
1 stop8h 43m
Delta
Tue 3/247:20 pm
MDW
- SAN
1 stop6h 20m
Delta
Deal found 2/18![Delta logo]()
$237
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 5/239:59 pm
SAN
- RFD
1 stop12h 22m
Multiple Airlines
Mon 5/259:13 pm
RFD
- SAN
1 stop14h 14m
Multiple Airlines
Deal found 2/21![Multiple Airlines logo]()
$356
Last-minute flights from San Diego to IllinoisDiscover last-minute flight deals from San Diego to Illinois. Data last updated February 23, 2026 and is based on user searches.
Discover last-minute flight deals from San Diego to Illinois. Data last updated February 23, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 2/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/1310:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Wed 3/185:45 am
MDW
- SAN
Nonstop4h 25m
Southwest
Deal found 2/20![Southwest logo]()
$167
This United Airlines deal was found by Cheapflights users on 2/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/142:11 pm
SAN
- ORD
Nonstop4h 09m
United Airlines
Tue 3/1712:45 pm
ORD
- SAN
1 stop7h 48m
United Airlines
Deal found 2/21![United Airlines logo]()
$166
This CheapOair deal was found by Cheapflights users on 2/20. 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.
Sat 3/145:42 pm
SAN
- ORD
Nonstop4h 17m
Alaska Airlines
Wed 3/254:10 pm
ORD
- SAN
Nonstop4h 45m
Alaska Airlines
Deal found 2/20![Alaska Airlines logo]()
$167
This Southwest deal was found by Cheapflights users on 2/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/1410:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Tue 3/175:45 am
MDW
- SAN
Nonstop4h 25m
Southwest
Deal found 2/21![Southwest logo]()
$169
This SmartFares deal was found by Cheapflights users on 2/20. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/155:42 pm
SAN
- ORD
Nonstop4h 17m
Alaska Airlines
Tue 3/248:20 am
ORD
- SAN
Nonstop4h 42m
Alaska Airlines
Deal found 2/20![Alaska Airlines logo]()
$164
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 3/169:00 am
SAN
- ORD
1 stop13h 57m
Multiple Airlines
Tue 3/244:36 pm
ORD
- SAN
2 stops22h 37m
Multiple Airlines
Deal found 2/22![Multiple Airlines logo]()
$169
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/172:08 pm
SAN
- ORD
1 stop14h 00m
Frontier
Tue 3/248:55 pm
ORD
- SAN
1 stop18h 18m
Frontier
Deal found 2/20![Frontier logo]()
$163
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 3/2310:13 pm
SAN
- STL
2 stops33h 36m
Frontier
Mon 3/308:12 pm
STL
- SAN
1 stop27h 02m
Frontier
Deal found 2/21![Frontier logo]()
$162
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 3/2310:13 pm
SAN
- ORD
2 stops29h 55m
Frontier
Mon 3/308:55 pm
ORD
- SAN
1 stop18h 18m
Frontier
Deal found 2/21![Frontier logo]()
$172
This United Airlines deal was found by Cheapflights users on 2/20. 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.
Tue 3/245:00 pm
SAN
- ORD
Nonstop3h 59m
United Airlines
Mon 3/308:20 pm
ORD
- SAN
Nonstop4h 39m
United Airlines
Deal found 2/20![United Airlines logo]()
$170
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 3/318:25 am
SAN
- STL
1 stop23h 23m
Frontier
Fri 4/38:16 pm
STL
- SAN
1 stop29h 46m
Frontier
Deal found 2/21![Frontier logo]()
$139
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/318:25 am
SAN
- ORD
2 stops26h 14m
Frontier
Wed 4/83:29 pm
ORD
- SAN
1 stop10h 33m
Frontier
Deal found 2/20![Frontier logo]()
$168
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 February 23, 2026.
Search for one-way flight options from San Diego to Illinois. Find affordable one-way fares based on user searches. Data last updated February 23, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/178:25 am
SAN
- STL
1 stop23h 24m
Frontier
Deal found 2/20![Frontier logo]()
$67
This Trip.com deal was found by Cheapflights users on 2/19. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/156:25 am
SAN
- STL
1 stop25h 24m
Frontier
Deal found 2/19![Frontier logo]()
$68
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 4/59:28 pm
SAN
- STL
1 stop10h 20m
Frontier
Deal found 2/22![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/242:08 pm
SAN
- ORD
1 stop14h 00m
Frontier
Deal found 2/20![Frontier logo]()
$79
This Southwest deal was found by Cheapflights users on 2/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/510:40 pm
SAN
- MDW
Nonstop3h 55m
Southwest
Deal found 2/20![Southwest logo]()
$79
This Kiwi.com deal was found by Cheapflights users on 2/21. 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.
Thu 4/166:25 am
SAN
- STL
1 stop10h 56m
Frontier
Deal found 2/21![Frontier logo]()
$79
This Kiwi.com deal was found by Cheapflights users on 2/19. 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.
Thu 4/1612:25 pm
SAN
- ORD
1 stop19h 25m
Frontier
Deal found 2/19![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/1512:29 pm
SAN
- MDW
1 stop24h 35m
Frontier
Deal found 2/20![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 2/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1712:25 pm
SAN
- STL
1 stop29h 07m
Frontier
Deal found 2/20![Frontier logo]()
$82
This Trip.com deal was found by Cheapflights users on 2/20. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/178:49 pm
SAN
- ORD
1 stop7h 19m
Frontier
Deal found 2/20![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 2/19. 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.
Thu 3/195:38 pm
SAN
- ORD
Nonstop4h 21m
Hawaiian Airlines
Deal found 2/19![Hawaiian Airlines logo]()
$84
This Kiwi.com deal was found by Cheapflights users on 2/18. 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 3/183:16 pm
SAN
- ORD
1 stop22h 43m
Frontier
Deal found 2/18![Frontier logo]()
$86
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 February 23, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $139 (Kiwi.com) |
One-way from | $67 (Kiwi.com) |
Popular in | April |
Cheapest in | October |
Average price | $267 |
Good round-trip deal | $282 or less |
Good one-way deal | $147 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 February 23, 2026.
Use the filters below to find and compare flights from San Diego to Illinois that are best for you.
Fly from
San Diego
Fly to
Illinois
Route
Depart
Return
Price
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Wed 3/18
6:30 am-12:35 pm
Nonstop4h 05m
Chicago Midway
Mon 3/23
8:55 pm-11:25 pm
Nonstop4h 30m
$177
San DiegoChicago
SAN - ORD
SANORD
San Diego
Wed 4/15
10:30 pm-4:35 am
Nonstop4h 05m
Chicago O'Hare Intl
Mon 4/20
6:00 pm-11:59 pm
1 stop7h 59m
$187
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Sat 4/18
10:40 pm-6:50 am
1 stop6h 10m
Chicago Midway
Wed 4/22
6:45 am-9:00 am
Nonstop4h 15m
$187
San DiegoChicago
SAN - ORD
SANORD
San Diego
Thu 3/19
7:55 am-2:21 pm
Nonstop4h 26m
Chicago O'Hare Intl
Mon 3/23
7:59 pm-10:41 pm
Nonstop4h 42m
$197
San DiegoChicago
SAN - ORD
SANORD
San Diego
Thu 4/9
12:37 pm-7:02 pm
Nonstop4h 25m
Chicago O'Hare Intl
Mon 4/13
7:59 pm-10:41 pm
Nonstop4h 42m
$197
San DiegoChicago
SAN - RFD
SANRFD
San Diego
Thu 4/30
7:23 pm-7:45 pm
1 stop22h 22m
Chicago Greater Rockford
Mon 5/4
8:35 pm-11:34 am
1 stop16h 59m
$202
San DiegoChicago
SAN - ORD
SANORD
San Diego
Wed 4/8
12:40 pm-9:20 pm
1 stop6h 40m
Chicago O'Hare Intl
Sun 4/12
7:00 am-9:40 am
Nonstop4h 40m
$207
San DiegoChicago
SAN - ORD
SANORD
San Diego
Tue 3/17
8:26 pm-6:39 am
1 stop8h 13m
Chicago O'Hare Intl
Tue 3/24
8:20 am-11:02 am
Nonstop4h 42m
$207
San DiegoChicago
SAN - ORD
SANORD
San Diego
Thu 4/30
7:03 am-1:13 pm
Nonstop4h 10m
Chicago O'Hare Intl
Wed 5/6
8:50 am-11:30 am
Nonstop4h 40m
$207
San DiegoChicago
SAN - MDW
SANMDW
San Diego
Wed 4/15
12:29 pm-3:04 pm
1 stop24h 35m
Chicago Midway
Mon 4/20
4:14 pm-11:41 pm
1 stop9h 27m
$212
Showing 1-10 of 60 results
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-MDW
SAN-ORD
SAN-RFD
SAN-STL
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-MDW
SAN-ORD
SAN-RFD
SAN-STL
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 $98). Flying from San Diego to Illinois in May is currently the most expensive (average of $177). 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 February 23, 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 31% 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 February 17, 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. Sunday 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 February 23, 2026.
The most flights from SAN to USIL are scheduled on a Friday (34 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (22 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 February 23, 2026.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and United Airlines from San Diego to Illinois. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
Crew
8.5
Comfort
7.8
Entertainment
7.0
Food
7.1
Boarding
8.1
Overall
8.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Jan 2026
STS - LAX
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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Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
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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 February 23, 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 February 23, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$98 | Average$182 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$109 | Average$213 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$139 | Average$197 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$139 | Average$266 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$158 | Average$451 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$171 | Average$440 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$205 | Average$362 | FlexibilityNo cancel fee | On-time63% |