$86+ Cheap flights from San Diego (SAN) to Illinois
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/1. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ORD
Oct 5 — Oct 121
Round-trip
1 adult, Economy
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Find cheap flights from San Diego to Illinois with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Cheapest flights from 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 September 5, 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 September 5, 2026.
This CheapOair deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/204:53 pm -
1 stop20h 31m
Mon 10/268:00 pm -
1 stop21h 58m
Deal found 9/2![Frontier logo]()
$181
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/306:25 am -
1 stop10h 52m
Wed 10/78:10 pm -
1 stop5h 41m
Deal found 9/2![Frontier logo]()
$193
This Kiwi.com deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:54 pm -
1 stop24h 23m
Sat 10/38:10 pm -
1 stop29h 41m
Deal found 8/31![Frontier logo]()
$198
This Expedia deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:25 am -
1 stop15h 34m
Fri 10/168:00 pm -
1 stop21h 58m
Deal found 9/3![Frontier logo]()
$203
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/34:53 pm -
1 stop20h 30m
Wed 11/184:18 pm -
1 stop9h 39m
Deal found 9/1![Frontier logo]()
$214
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/224:53 pm -
1 stop24h 22m
Mon 10/268:00 pm -
1 stop21h 58m
Deal found 9/2![Frontier logo]()
$217
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/236:25 am -
1 stop10h 52m
Wed 9/308:10 pm -
1 stop29h 41m
Deal found 9/1![Frontier logo]()
$220
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/244:54 pm -
1 stop24h 23m
Mon 9/288:10 pm -
1 stop21h 49m
Deal found 9/1![Frontier logo]()
$221
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:54 pm -
1 stop24h 23m
Tue 9/2912:17 pm -
1 stop6h 42m
Deal found 9/2![Frontier logo]()
$222
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/94:53 pm -
1 stop29h 31m
Sat 10/176:30 am -
1 stop11h 28m
Deal found 9/3![Frontier logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/152:01 pm -
1 stop19h 26m
Sun 10/189:33 pm -
1 stop24h 16m
Deal found 9/2![Multiple Airlines logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/192:01 pm -
1 stop8h 58m
Fri 10/238:01 pm -
2 stops43h 15m
Deal found 9/3![Frontier logo]()
$245
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 September 5, 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 September 5, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/305:54 pm -
1 stop24h 19m
Sun 10/49:36 pm -
2 stops22h 33m
Deal found 9/3![Multiple Airlines logo]()
$256
This Southwest deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/33:35 pm -
1 stop6h 35m
Tue 10/135:45 am -
1 stop7h 00m
Deal found 8/31![Southwest logo]()
$257
This United Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/2810:30 pm -
Nonstop4h 04m
Thu 10/298:50 am -
Nonstop4h 37m
Deal found 9/4![United Airlines logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/155:46 pm -
Nonstop4h 13m
Mon 10/197:20 am -
Nonstop4h 36m
Deal found 9/4![Alaska Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:20 pm -
1 stop9h 09m
Thu 10/85:35 pm -
1 stop7h 49m
Deal found 9/3![Delta logo]()
$307
This American Airlines deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/21:10 pm -
1 stop8h 53m
Thu 10/82:30 pm -
1 stop9h 03m
Deal found 9/2![American Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1310:40 pm -
Nonstop3h 50m
Mon 10/199:25 pm -
Nonstop4h 25m
Deal found 9/1![Southwest logo]()
$257
This United Airlines deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/284:55 pm -
Nonstop4h 04m
Wed 9/307:05 am -
Nonstop4h 27m
Deal found 9/3![United Airlines logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/307:03 am -
Nonstop4h 19m
Tue 10/69:00 am -
1 stop10h 52m
Deal found 9/1![Alaska Airlines logo]()
$277
This Southwest deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/75:00 pm -
Nonstop3h 50m
Mon 11/910:00 am -
1 stop6h 20m
Deal found 9/1![Southwest logo]()
$267
This Alaska Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/261:03 pm -
Nonstop4h 18m
Mon 9/287:20 am -
Nonstop4h 40m
Deal found 9/4![Alaska Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/247:45 am -
2 stops11h 24m
Sat 10/316:21 am -
2 stops10h 43m
Deal found 9/4![Delta logo]()
$313
This Kiwi.com deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 10/152:01 pm -
1 stop19h 26m
Sun 10/189:33 pm -
1 stop24h 16m
Deal found 9/5![Multiple Airlines logo]()
$316
This Alaska Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:27 pm -
1 stop20h 53m
Thu 10/223:49 pm -
1 stop10h 10m
Deal found 9/4![Alaska Airlines logo]()
$283
This Southwest deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2610:40 pm -
Nonstop3h 50m
Tue 9/292:05 pm -
1 stop6h 15m
Deal found 9/2![Southwest logo]()
$283
This United Airlines deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/22:07 pm -
Nonstop4h 21m
Sun 10/48:16 pm -
Nonstop4h 25m
Deal found 9/3![United Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/126:15 am -
1 stop8h 59m
Mon 11/162:20 pm -
2 stops10h 34m
Deal found 8/31![Delta logo]()
$320
This American Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 10/221:12 pm -
1 stop8h 59m
Mon 10/265:02 pm -
1 stop6h 39m
Deal found 9/5![American Airlines logo]()
$359
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/82:01 pm -
1 stop19h 26m
Sun 10/119:33 pm -
2 stops18h 56m
Deal found 9/1![Multiple Airlines logo]()
$349
This Alaska Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 9/251:03 pm -
Nonstop4h 18m
Tue 9/297:20 am -
Nonstop4h 40m
Deal found 9/4![Alaska Airlines logo]()
$289
This Southwest deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/26:45 pm -
Nonstop3h 50m
Mon 10/59:25 pm -
Nonstop4h 25m
Deal found 9/4![Southwest logo]()
$289
This Delta deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/1311:39 am -
1 stop6h 50m
Tue 11/176:13 am -
2 stops10h 37m
Deal found 8/31![Delta logo]()
$320
This Delta deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/196:15 am -
1 stop7h 59m
Sat 9/266:10 am -
1 stop9h 08m
Deal found 8/31![Delta logo]()
$326
This United Airlines deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/202:24 pm -
2 stops7h 20m
Wed 10/215:10 am -
1 stop5h 55m
Deal found 9/2![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/106:30 am -
Nonstop3h 50m
Sat 10/103:10 pm -
1 stop8h 00m
Deal found 9/2![Southwest logo]()
$297
This Kiwi.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/247:04 pm -
1 stop21h 07m
Wed 9/302:07 pm -
1 stop21h 36m
Deal found 9/2![Multiple Airlines logo]()
$367
This American Airlines deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 12/161:29 pm -
1 stop8h 30m
Sun 12/203:58 pm -
1 stop7h 09m
Deal found 9/4![American Airlines logo]()
$427
This Southwest deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/610:40 pm -
Nonstop3h 45m
Mon 11/95:45 am -
1 stop6h 30m
Deal found 8/31![Southwest logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/2012:41 pm -
Nonstop4h 18m
Mon 11/307:57 pm -
Nonstop4h 55m
Deal found 8/31![Alaska Airlines logo]()
$334
This Delta deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/276:15 am -
1 stop7h 58m
Fri 10/92:45 pm -
1 stop6h 29m
Deal found 8/31![Delta logo]()
$339
Last-minute flights from San Diego to IllinoisDiscover last-minute flight deals from San Diego to Illinois. Data last updated September 5, 2026 and is based on user searches.
Discover last-minute flight deals from San Diego to Illinois. Data last updated September 5, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/236:25 am -
1 stop10h 52m
Wed 9/308:10 pm -
1 stop29h 41m
Deal found 9/1![Frontier logo]()
$220
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/244:54 pm -
1 stop24h 23m
Mon 9/288:10 pm -
1 stop21h 49m
Deal found 9/1![Frontier logo]()
$221
This Kiwi.com deal was found by Cheapflights users on 8/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:54 pm -
1 stop24h 23m
Sat 10/38:10 pm -
1 stop29h 41m
Deal found 8/31![Frontier logo]()
$198
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:54 pm -
1 stop24h 23m
Tue 9/2912:17 pm -
1 stop6h 42m
Deal found 9/2![Frontier logo]()
$222
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/294:54 pm -
1 stop24h 23m
Tue 10/612:17 pm -
2 stops13h 34m
Deal found 9/1![Frontier logo]()
$224
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/306:25 am -
1 stop10h 52m
Wed 10/78:10 pm -
1 stop5h 41m
Deal found 9/2![Frontier logo]()
$193
This Expedia deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:25 am -
1 stop15h 34m
Fri 10/168:00 pm -
1 stop21h 58m
Deal found 9/3![Frontier logo]()
$203
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/94:53 pm -
1 stop29h 31m
Sat 10/176:30 am -
1 stop11h 28m
Deal found 9/3![Frontier logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/152:01 pm -
1 stop19h 26m
Sun 10/189:33 pm -
1 stop24h 16m
Deal found 9/2![Multiple Airlines logo]()
$244
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/192:01 pm -
1 stop8h 58m
Fri 10/238:01 pm -
2 stops43h 15m
Deal found 9/3![Frontier logo]()
$245
This CheapOair deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/204:53 pm -
1 stop20h 31m
Mon 10/268:00 pm -
1 stop21h 58m
Deal found 9/2![Frontier logo]()
$181
This Expedia deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/224:53 pm -
1 stop24h 22m
Mon 10/268:00 pm -
1 stop21h 58m
Deal found 9/2![Frontier logo]()
$217
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 September 5, 2026.
Search for one-way flight options from San Diego to Illinois. Find affordable one-way fares based on user searches. Data last updated September 5, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/14:41 pm -
1 stop24h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Frontier logo]()
$86
This Super.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/174:53 pm -
1 stop20h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$87
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/306:25 am -
1 stop10h 52m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Frontier logo]()
$95
This Super.com deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/204:53 pm -
1 stop20h 31m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$97
This Priceline deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/26:25 am -
1 stop10h 29m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$98
This Super.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/146:25 am -
1 stop6h 59m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$101
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/294:54 pm -
1 stop24h 23m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Frontier logo]()
$106
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/56:25 am -
1 stop10h 29m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$107
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/316:25 am -
1 stop10h 49m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$108
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/46:25 am -
1 stop6h 58m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$109
This CheapOair deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 11/34:53 pm -
1 stop20h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$110
This Kiwi.com deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/152:01 pm -
1 stop8h 58m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$122
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 September 5, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $181 (CheapOair) |
One-way from | $86 (Kiwi.com) |
Popular in | July |
Cheapest in | February |
Average price | $297 |
Good round-trip deal | $334 or less |
Good one-way deal | $178 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 7,457,451 searches. Data last updated September 5, 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 San Diego - RFD Chicago Greater Rockford
SANRFD
San Diego
Thu 12/3
3:44 pm-12:11 pm
1 stop18h 27m
Chicago Greater Rockford
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$126
San DiegoSt. Louis
SAN San Diego - STL Lambert-St Louis
SANSTL
San Diego
Tue 10/6
6:25 am-1:10 pm
2 stops28h 45m
Lambert-St Louis
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$128
San DiegoChicago
SAN San Diego - ORD Chicago O'Hare Intl
SANORD
San Diego
Thu 11/5
12:41 pm-6:59 pm
Nonstop4h 18m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - ORD Chicago O'Hare Intl
SANORD
San Diego
Mon 10/19
10:30 pm-4:33 am
Nonstop4h 03m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - ORD Chicago O'Hare Intl
SANORD
San Diego
Tue 11/17
10:59 am-8:49 pm
1 stop7h 50m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - MDW Chicago Midway
SANMDW
San Diego
Thu 12/3
4:05 pm-9:55 pm
Nonstop3h 50m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - ORD Chicago O'Hare Intl
SANORD
San Diego
Mon 11/2
5:35 pm-11:49 pm
Nonstop4h 14m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - MDW Chicago Midway
SANMDW
San Diego
Tue 9/29
10:40 pm-4:30 am
Nonstop3h 50m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - ORD Chicago O'Hare Intl
SANORD
San Diego
Wed 9/30
7:03 am-1:22 pm
Nonstop4h 19m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
San DiegoChicago
SAN San Diego - MDW Chicago Midway
SANMDW
San Diego
Mon 12/14
6:30 am-12:30 pm
Nonstop4h 00m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$139
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-RFD
SAN-MDW
SAN-ORD
SAN-STL
SAN-BMI
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-RFD
SAN-MDW
SAN-ORD
SAN-STL
What is the cheapest month to book a flight from San Diego to Illinois?
Currently, February is the cheapest month in which you can book a flight from San Diego to Illinois (average of $251). Flying from San Diego to Illinois in July is currently the most expensive (average of $388). 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 September 5, 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 25% versus a flight at noon.
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 September 5, 2026.
The most flights from SAN to USIL are scheduled on a Friday (54 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (8 on average).
How much does it cost to fly round-trip from San Diego to Illinois?
Airfare is below average for this route at the moment.
San Diego to Illinois flights typically cost between $267 and $387 in October.The cheapest round-trip price found within the last 5 days was $244 on Frontier (Oct 9-Oct 17).
How far ahead should I book a flight from San Diego to Illinois?
To ensure you get the cheapest price possible for a flight from San Diego to Illinois, you should look to book at least 62 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
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 September 5, 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.
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 September 5, 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.
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
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
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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.
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 September 5, 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 5 airlines flying from San Diego to Illinois
Discover the top 5 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 7,457,451 searches. Data last updated September 5, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$122 | Average$270 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$157 | Average$324 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$167 | Average$478 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$177 | Average$408 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$222 | Average$381 | FlexibilityNo cancel fee | On-time63% |