$82+ Cheap flights from Illinois to San Diego (SAN)
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 10/3. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SAN
Oct 5 — Oct 121
Round-trip
1 adult, Economy
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Find cheap flights from Illinois to San Diego 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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Illinois to San Diego
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Cheapest flights from Illinois to San DiegoExplore the most affordable flight options available from Illinois to San Diego. 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 Illinois to San Diego. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 5, 2026.
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.
Wed 10/76:30 am -
1 stop11h 29m
Mon 10/128:34 pm -
2 stops32h 00m
Deal found 9/2![Frontier logo]()
$246
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 9/262:05 pm -
Nonstop4h 05m
Sat 10/312:55 pm -
Nonstop3h 50m
Deal found 9/1![Southwest logo]()
$247
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/235:00 am -
1 stop6h 05m
Sat 9/2610:30 pm -
Nonstop4h 03m
Deal found 8/31![United Airlines logo]()
$247
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:55 pm -
1 stop22h 04m
Thu 10/19:03 pm -
1 stop6h 35m
Deal found 9/1![Frontier logo]()
$248
This SmartFares 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/248:17 pm -
Nonstop4h 43m
Wed 9/307:03 am -
Nonstop4h 19m
Deal found 9/3![Alaska Airlines logo]()
$249
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 10/28:55 pm -
1 stop22h 04m
Mon 10/59:03 pm -
1 stop6h 35m
Deal found 9/2![Frontier logo]()
$250
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/286:30 am -
1 stop19h 21m
Tue 9/297:03 am -
Nonstop4h 19m
Deal found 9/1![Multiple Airlines logo]()
$251
This Priceline 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/142:21 pm -
Nonstop4h 40m
Mon 10/192:01 pm -
1 stop8h 58m
Deal found 9/2![Multiple Airlines logo]()
$252
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.
Sat 9/266:30 am -
1 stop19h 21m
Tue 9/297:03 am -
Nonstop4h 19m
Deal found 9/2![Multiple Airlines logo]()
$253
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.
Sat 10/246:30 am -
1 stop19h 26m
Tue 10/276:25 am -
1 stop15h 56m
Deal found 9/2![Frontier logo]()
$254
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.
Sat 9/266:30 am -
1 stop19h 21m
Tue 9/2910:28 am -
2 stops17h 10m
Deal found 9/2![Frontier logo]()
$255
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.
Sat 10/247:42 pm -
2 stops19h 34m
Sat 10/316:25 am -
1 stop10h 49m
Deal found 9/1![Frontier logo]()
$255
Best flights from Illinois to San DiegoDiscover carefully curated flight deals from Illinois to San Diego 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 Illinois to San Diego that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 5, 2026.
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.
Thu 12/38:55 pm -
Nonstop4h 25m
Mon 12/74:05 pm -
Nonstop3h 50m
Deal found 9/4![Southwest logo]()
$277
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.
Wed 10/148:16 pm -
Nonstop4h 25m
Mon 10/194:55 pm -
Nonstop4h 04m
Deal found 9/3![United Airlines logo]()
$277
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1011:09 am -
1 stop8h 46m
Wed 10/143:00 pm -
1 stop6h 47m
Deal found 9/1![Delta logo]()
$277
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/292:18 pm -
Nonstop4h 37m
Sat 10/37:00 am -
Nonstop4h 25m
Deal found 9/2![Alaska Airlines logo]()
$277
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/56:01 am -
1 stop8h 10m
Thu 12/1012:28 pm -
1 stop8h 49m
Deal found 8/31![American Airlines logo]()
$359
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.
Wed 10/148:16 pm -
Nonstop4h 25m
Mon 10/2610:30 pm -
Nonstop4h 04m
Deal found 9/3![United Airlines logo]()
$277
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/227:20 am -
Nonstop4h 36m
Mon 10/267:00 am -
Nonstop4h 25m
Deal found 9/3![Alaska Airlines logo]()
$277
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 10/235:25 am -
Nonstop4h 25m
Mon 10/266:55 pm -
Nonstop3h 55m
Deal found 8/31![Southwest logo]()
$289
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.
Sat 10/246:04 am -
1 stop7h 09m
Wed 10/286:15 am -
1 stop9h 45m
Deal found 9/3![Delta logo]()
$297
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.
Thu 10/228:16 pm -
Nonstop4h 25m
Mon 10/266:50 am -
Nonstop4h 19m
Deal found 9/2![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.
Fri 10/237:16 pm -
1 stop16h 50m
Mon 10/268:28 pm -
1 stop19h 52m
Deal found 9/4![Alaska Airlines logo]()
$283
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.
Fri 1/810:10 am -
Nonstop4h 30m
Tue 1/1210:55 am -
Nonstop3h 50m
Deal found 9/1![Southwest logo]()
$289
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.
Sat 10/246:04 am -
1 stop7h 09m
Tue 10/2712:38 pm -
1 stop7h 55m
Deal found 9/3![Delta logo]()
$297
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.
Sat 10/108:16 pm -
Nonstop4h 25m
Mon 10/1210:30 pm -
Nonstop4h 03m
Deal found 9/4![United Airlines logo]()
$277
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.
Fri 10/29:25 pm -
Nonstop4h 20m
Mon 10/56:45 pm -
Nonstop3h 55m
Deal found 9/2![Southwest logo]()
$289
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.
Tue 9/2910:48 am -
1 stop8h 17m
Sat 10/312:52 pm -
1 stop7h 52m
Deal found 9/3![Delta logo]()
$297
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.
Wed 10/143:49 pm -
1 stop9h 37m
Mon 10/195:46 pm -
Nonstop4h 13m
Deal found 9/4![Alaska Airlines logo]()
$297
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/144:42 pm -
1 stop8h 56m
Sat 10/176:18 am -
1 stop8h 41m
Deal found 8/31![American Airlines logo]()
$377
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.
Wed 11/259:15 pm -
Nonstop4h 35m
Wed 12/29:15 am -
1 stop6h 05m
Deal found 9/4![Southwest logo]()
$299
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.
Tue 10/278:00 am -
1 stop7h 47m
Fri 10/302:08 pm -
1 stop7h 16m
Deal found 9/4![United Airlines logo]()
$302
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/77:20 am -
Nonstop4h 36m
Sun 10/117:00 am -
Nonstop4h 25m
Deal found 9/2![Alaska Airlines logo]()
$307
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.
Tue 12/156:03 am -
1 stop9h 00m
Tue 1/56:20 am -
1 stop6h 11m
Deal found 8/31![Delta logo]()
$307
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/266:14 am -
1 stop6h 24m
Sat 10/311:53 pm -
1 stop7h 31m
Deal found 8/31![American Airlines logo]()
$387
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 12/48:55 pm -
Nonstop4h 25m
Tue 12/88:15 am -
2 stops7h 05m
Deal found 8/31![Southwest logo]()
$304
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 9/266:00 am -
1 stop10h 42m
Wed 9/301:03 pm -
Nonstop4h 18m
Deal found 9/4![Alaska Airlines logo]()
$309
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/145:00 am -
1 stop8h 27m
Tue 11/176:50 am -
1 stop8h 52m
Deal found 8/31![United Airlines logo]()
$323
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 10/176:47 am -
1 stop9h 33m
Mon 10/199:45 pm -
1 stop9h 24m
Deal found 9/4![Delta logo]()
$327
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.
Fri 10/92:30 pm -
1 stop9h 03m
Mon 10/121:12 pm -
1 stop8h 47m
Deal found 9/4![American Airlines logo]()
$407
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.
Wed 11/187:00 am -
1 stop9h 47m
Sun 11/225:32 pm -
Nonstop4h 17m
Deal found 9/4![Alaska Airlines logo]()
$310
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.
Fri 10/26:15 pm -
1 stop7h 00m
Fri 10/96:45 pm -
Nonstop3h 55m
Deal found 9/1![Southwest logo]()
$311
Last-minute flights from Illinois to San DiegoDiscover last-minute flight deals from Illinois to San Diego. Data last updated September 5, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to San Diego. Data last updated September 5, 2026 and is based on user searches.
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/235:00 am -
1 stop6h 05m
Sat 9/2610:30 pm -
Nonstop4h 03m
Deal found 8/31![United Airlines logo]()
$247
This SmartFares 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/248:17 pm -
Nonstop4h 43m
Wed 9/307:03 am -
Nonstop4h 19m
Deal found 9/3![Alaska Airlines logo]()
$249
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 9/262:05 pm -
Nonstop4h 05m
Sat 10/310:40 pm -
Nonstop3h 50m
Deal found 9/1![Southwest logo]()
$247
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.
Sat 9/266:30 am -
1 stop19h 21m
Tue 9/297:03 am -
Nonstop4h 19m
Deal found 9/2![Multiple Airlines logo]()
$253
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.
Sat 9/266:30 am -
1 stop19h 21m
Tue 9/2910:28 am -
2 stops17h 10m
Deal found 9/2![Frontier logo]()
$255
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:55 pm -
1 stop22h 04m
Thu 10/19:03 pm -
1 stop6h 35m
Deal found 9/1![Frontier logo]()
$248
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/286:30 am -
1 stop19h 21m
Tue 9/297:03 am -
Nonstop4h 19m
Deal found 9/1![Multiple Airlines logo]()
$251
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 10/28:55 pm -
1 stop22h 04m
Mon 10/59:03 pm -
1 stop6h 35m
Deal found 9/2![Frontier logo]()
$250
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.
Wed 10/76:30 am -
1 stop11h 29m
Mon 10/128:34 pm -
2 stops32h 00m
Deal found 9/2![Frontier logo]()
$246
This Priceline 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/142:21 pm -
Nonstop4h 40m
Mon 10/192:01 pm -
1 stop8h 58m
Deal found 9/2![Multiple Airlines logo]()
$252
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.
Sat 10/246:30 am -
1 stop19h 26m
Tue 10/276:25 am -
1 stop15h 56m
Deal found 9/2![Frontier logo]()
$254
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.
Sat 10/247:42 pm -
2 stops19h 34m
Sat 10/316:25 am -
1 stop10h 49m
Deal found 9/1![Frontier logo]()
$255
One-way flights from Illinois to San DiegoSearch for one-way flight options from Illinois to San Diego. Find affordable one-way fares based on user searches. Data last updated September 5, 2026.
Search for one-way flight options from Illinois to San Diego. Find affordable one-way fares based on user searches. Data last updated September 5, 2026.
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.
Sat 10/38:10 pm -
1 stop5h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$82
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.
Mon 9/288:10 pm -
1 stop29h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$97
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.
Sat 10/317:59 pm -
1 stop5h 58m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$105
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.
Mon 10/58:10 pm -
1 stop29h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$106
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.
Mon 11/27:59 pm -
1 stop21h 59m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/4![Frontier logo]()
$108
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 10/284:18 pm -
1 stop9h 39m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Frontier logo]()
$111
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.
Fri 10/28:10 pm -
1 stop29h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$116
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.
Wed 10/286:30 am -
2 stops29h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 8/31![Frontier logo]()
$122
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/36:30 am -
1 stop11h 28m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$123
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 9/261:45 pm -
1 stop5h 25m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 8/31![Southwest logo]()
$124
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/262:32 pm -
1 stop8h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 8/31![United Airlines logo]()
$124
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/296:30 am -
1 stop11h 29m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$125
Find flight deals from Illinois to San Diego
Keep the following information in mind while searching for Illinois to San Diego flight deals. Data was last updated September 5, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $246 (Kiwi.com) |
One-way from | $82 (Super.com) |
Popular in | June |
Cheapest in | January |
Average price | $296 |
Good round-trip deal | $285 or less |
Good one-way deal | $123 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois to San Diego 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 Illinois to San Diego that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
ChicagoSan Diego
MDW Chicago Midway - SAN San Diego
MDWSAN
Chicago Midway
Tue 10/13
5:45 am-10:45 am
1 stop7h 00m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$129
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Tue 10/13
5:00 am-9:05 am
1 stop6h 05m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$129
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Thu 10/8
2:21 pm-5:01 pm
Nonstop4h 40m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
Quickest round-trip
ChicagoSan Diego
MDW Chicago Midway - SAN San Diego
MDWSAN
Chicago Midway
Wed 9/30
8:25 pm-10:40 pm
Nonstop4h 15m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Tue 10/6
7:20 am-9:56 am
Nonstop4h 36m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Sat 9/26
8:16 pm-10:41 pm
Nonstop4h 25m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Mon 10/19
7:49 pm-10:27 pm
Nonstop4h 38m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Sat 10/10
8:16 pm-10:41 pm
Nonstop4h 25m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
ORD Chicago O'Hare Intl - SAN San Diego
ORDSAN
Chicago O'Hare Intl
Thu 12/3
9:20 am-11:45 am
Nonstop4h 25m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$139
ChicagoSan Diego
MDW Chicago Midway - SAN San Diego
MDWSAN
Chicago Midway
Thu 10/1
1:00 pm-9:00 pm
1 stop10h 00m
San Diego
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$149
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Illinois to San Diego
Have a flexible travel schedule? Discover the best time to fly to San Diego from Illinois with our price prediction graph.
MDW-SAN
ORD-SAN
EVV-SAN
MLI-SAN
STL-SAN
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Illinois to San Diego
USIL-SAN
MDW-SAN
ORD-SAN
EVV-SAN
MLI-SAN
What is the cheapest month to book a flight from Illinois to San Diego?
Currently, February is the cheapest month in which you can book a flight from Illinois to San Diego (average of $250). Flying from Illinois to San Diego in July is currently the most expensive (average of $374). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from IL to SAN?
Find hourly flight availability from Illinois to San Diego. 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.
A simple way to save on the total cost of your ticket is to fly from Illinois to San Diego in the evening. If you’re flexible enough to do this you can expect to save up to 28% on your trip compared to booking a flight at noon.
Weekly flight availability from Illinois to San Diego
Explore weekly flight availability from Illinois to San Diego. 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 USIL to SAN are scheduled on a Thursday (54 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (23 on average).
How much does it cost to fly round-trip from Illinois to San Diego?
Airfare is below average for this route at the moment.
Illinois to San Diego flights typically cost between $270 and $393 in October.The cheapest round-trip price found within the last 5 days was $246 on Frontier (Oct 7-Oct 12).
How far ahead should I book a flight from Illinois to San Diego?
To ensure you get the cheapest price possible for a flight from Illinois to San Diego, you should look to book at least 47 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 Illinois to San Diego?
Use this chart to determine the cheapest time to fly round-trip from Illinois to San Diego. Price data was last updated on September 5, 2026.
Travelers seeking maximum savings on their Illinois to San Diego flight should consider departing on Tuesday at noon when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Related info for your journey
Find useful and relevant information for your journey from Illinois to San Diego. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near San Diego?
Book flights to San Diego if you plan to visit one of these locationsEl Cajon
National City
Chula Vista
Coronado
Poway
San Ysidro
La Mesa
Santee
Julian
Lemon Grove
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Alternative routes for Illinois to San Diego
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Complete your trip
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Search flights from Illinois to San Diego by cabin class
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Illinois and San Diego flights
Browse other Illinois and San Diego flight options. Last updated on September 5, 2026.
Popular flight searches
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Other flights to San Diego
Explore flights to San Diego departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 5, 2026.
Illinois to San Diego flights
Consider these flights traveling from Illinois to San Diego.
Top 7 airlines flying from Illinois to San Diego
Discover the top 7 airlines that operate flights from Illinois to San Diego. 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$77 | Average$257 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$153 | Average$230 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$155 | Average$309 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$159 | Average$393 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$166 | Average$461 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$181 | Average$349 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$186 | Average$328 | FlexibilityNo cancel fee | On-timeN/A |