$95+ Cheap flights from San Antonio (SAT) 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 9/29. Fares are subject to change and may not be available on all flights or dates of travel.
SAT — ORD
Aug 31 — Sep 71
Round-trip
1 adult, Economy
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Cheapest flights from San Antonio to IllinoisExplore the most affordable flight options available from San Antonio to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 1, 2026.
Explore the most affordable flight options available from San Antonio to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 9/158:20 pm
SAT
- STL
1 stop22h 57m
Frontier
Sun 9/208:10 pm
STL
- SAT
1 stop23h 15m
Frontier
Deal found 7/30![Frontier logo]()
$219
This Kiwi.com deal was found by Cheapflights users on 7/31. 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 10/1612:16 pm
SAT
- STL
1 stop6h 59m
Frontier
Mon 10/198:10 pm
STL
- SAT
1 stop15h 11m
Frontier
Deal found 7/31![Frontier logo]()
$230
This Frontier deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2210:24 pm
SAT
- STL
1 stop19h 26m
Frontier
Mon 8/247:58 pm
STL
- SAT
1 stop23h 33m
Frontier
Deal found 7/27![Frontier logo]()
$241
This Kiwi.com deal was found by Cheapflights users on 8/1. 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 9/28:26 pm
SAT
- STL
1 stop22h 47m
Frontier
Mon 9/148:10 pm
STL
- SAT
1 stop23h 15m
Frontier
Deal found 8/1![Frontier logo]()
$243
This Expedia deal was found by Cheapflights users on 7/31. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1810:05 am
SAT
- STL
1 stop6h 29m
Frontier
Mon 9/2812:17 pm
STL
- SAT
1 stop26h 03m
Frontier
Deal found 7/31![Frontier logo]()
$248
This Trip.com deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/163:19 pm
SAT
- STL
1 stop19h 58m
Frontier
Mon 9/2112:17 pm
STL
- SAT
1 stop8h 46m
Frontier
Deal found 7/27![Frontier logo]()
$257
This Expedia deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1412:39 pm
SAT
- STL
1 stop22h 53m
Frontier
Fri 9/188:10 pm
STL
- SAT
1 stop23h 15m
Frontier
Deal found 7/29![Frontier logo]()
$258
This Trip.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Mon 8/2410:24 pm
SAT
- STL
1 stop19h 26m
Frontier
Thu 8/277:58 pm
STL
- SAT
1 stop23h 33m
Frontier
Deal found 7/29![Frontier logo]()
$263
This Kiwi.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/138:20 pm
SAT
- STL
1 stop22h 57m
Frontier
Fri 9/188:10 pm
STL
- SAT
1 stop23h 15m
Frontier
Deal found 7/29![Frontier logo]()
$267
This CheapOair deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/148:20 pm
SAT
- ORD
1 stop28h 03m
Frontier
Wed 9/166:30 am
ORD
- SAT
1 stop12h 55m
Frontier
Deal found 7/29![Frontier logo]()
$268
This CheapOair deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 8/177:49 pm
SAT
- ORD
1 stop17h 47m
Frontier
Sat 8/222:41 pm
ORD
- SAT
1 stop28h 50m
Frontier
Deal found 7/30![Frontier logo]()
$269
This Trip.com deal was found by Cheapflights users on 7/31. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/410:24 pm
SAT
- STL
1 stop19h 26m
Frontier
Tue 9/86:45 pm
STL
- SAT
1 stop19h 35m
Frontier
Deal found 7/31![Frontier logo]()
$271
Best flights from San Antonio to IllinoisDiscover carefully curated flight deals from San Antonio to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 1, 2026.
Discover carefully curated flight deals from San Antonio to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 1, 2026.
This Southwest deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 8/262:50 pm
SAT
- MDW
Nonstop2h 35m
Southwest
Mon 8/3111:05 am
MDW
- SAT
Nonstop2h 35m
Southwest
Deal found 7/29![Southwest logo]()
$291
This Delta deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 10/155:30 am
SAT
- STL
1 stop5h 21m
Delta
Mon 10/197:20 pm
STL
- SAT
1 stop5h 13m
Delta
Deal found 7/27![Delta logo]()
$307
This Kiwi.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/228:20 pm
SAT
- RFD
2 stops42h 43m
Multiple Airlines
Thu 10/19:03 pm
RFD
- SAT
1 stop14h 41m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$314
This United Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/236:30 am
SAT
- MLI
1 stop5h 51m
United Airlines
Sun 9/65:40 am
MLI
- SAT
1 stop6h 12m
United Airlines
Deal found 7/30![United Airlines logo]()
$329
This American Airlines deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 8/2610:59 am
SAT
- PIA
1 stop4h 54m
American Airlines
Wed 9/24:43 pm
PIA
- SAT
1 stop6h 07m
American Airlines
Deal found 7/29![American Airlines logo]()
$329
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 10/19:20 am
SAT
- MDW
Nonstop2h 40m
Southwest
Mon 10/59:20 pm
MDW
- SAT
Nonstop2h 45m
Southwest
Deal found 7/27![Southwest logo]()
$297
This Delta deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/295:15 am
SAT
- MDW
1 stop7h 24m
Delta
Wed 9/95:37 pm
MDW
- SAT
1 stop5h 07m
Delta
Deal found 7/27![Delta logo]()
$317
This Kiwi.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/233:19 pm
SAT
- RFD
1 stop29h 20m
Multiple Airlines
Thu 10/19:03 pm
RFD
- SAT
1 stop14h 41m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$324
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 10/103:45 pm
SAT
- MDW
1 stop4h 10m
Southwest
Tue 10/138:45 pm
MDW
- SAT
Nonstop2h 45m
Southwest
Deal found 7/27![Southwest logo]()
$301
This United Airlines deal was found by Cheapflights users on 7/31. 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.
Mon 8/2412:55 pm
SAT
- ORD
Nonstop3h 00m
United Airlines
Thu 8/2712:47 pm
ORD
- SAT
1 stop4h 57m
United Airlines
Deal found 7/31![United Airlines logo]()
$333
This American Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 9/36:20 pm
SAT
- BMI
1 stop4h 33m
American Airlines
Mon 9/74:49 pm
BMI
- SAT
1 stop6h 01m
American Airlines
Deal found 7/30![American Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Mon 9/214:21 pm
SAT
- MDW
1 stop6h 23m
Delta
Thu 9/242:00 pm
MDW
- SAT
1 stop7h 22m
Delta
Deal found 7/29![Delta logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/155:29 pm
SAT
- ORD
2 stops19h 53m
Alaska Airlines
Tue 9/222:22 pm
ORD
- SAT
2 stops25h 57m
Alaska Airlines
Deal found 7/29![Alaska Airlines logo]()
$716
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/213:30 pm
SAT
- MDW
1 stop3h 50m
Southwest
Sat 10/310:40 am
MDW
- SAT
1 stop6h 20m
Southwest
Deal found 7/27![Southwest logo]()
$312
This American Airlines deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” 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 9/46:52 pm
SAT
- MLI
1 stop5h 16m
American Airlines
Mon 9/76:45 pm
MLI
- SAT
1 stop6h 03m
American Airlines
Deal found 7/28![American Airlines logo]()
$347
This United Airlines deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/1412:55 pm
SAT
- MLI
1 stop4h 50m
United Airlines
Mon 8/243:44 pm
MLI
- SAT
2 stops6h 55m
United Airlines
Deal found 7/27![United Airlines logo]()
$359
This Kiwi.com deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 9/303:19 pm
SAT
- RFD
1 stop28h 54m
Multiple Airlines
Sun 10/49:36 pm
RFD
- SAT
1 stop14h 08m
Multiple Airlines
Deal found 7/27![Multiple Airlines logo]()
$362
This Southwest deal was found by Cheapflights users on 7/31. 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 9/42:55 pm
SAT
- STL
1 stop6h 50m
Southwest
Sun 9/68:05 pm
STL
- SAT
Nonstop2h 10m
Southwest
Deal found 7/31![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 11/52:00 pm
SAT
- MLI
1 stop8h 30m
Delta
Sun 11/85:09 pm
MLI
- SAT
1 stop7h 24m
Delta
Deal found 7/29![Delta logo]()
$349
This American Airlines deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/146:00 am
SAT
- MLI
1 stop5h 02m
American Airlines
Sun 8/236:00 am
MLI
- SAT
1 stop6h 53m
American Airlines
Deal found 7/27![American Airlines logo]()
$354
This United Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 12/56:43 am
SAT
- MLI
1 stop5h 52m
United Airlines
Wed 12/95:42 pm
MLI
- SAT
1 stop5h 16m
United Airlines
Deal found 7/30![United Airlines logo]()
$383
This Southwest deal was found by Cheapflights users on 7/31. 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 8/283:30 pm
SAT
- STL
Nonstop2h 10m
Southwest
Fri 9/48:45 pm
STL
- SAT
Nonstop2h 15m
Southwest
Deal found 7/31![Southwest logo]()
$317
This American Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 8/146:52 pm
SAT
- BMI
1 stop5h 07m
American Airlines
Tue 8/181:46 pm
BMI
- SAT
2 stops9h 04m
American Airlines
Deal found 7/30![American Airlines logo]()
$354
This Kiwi.com deal was found by Cheapflights users on 7/31. 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 10/910:41 pm
SAT
- RFD
2 stops21h 27m
Multiple Airlines
Sun 10/119:33 pm
RFD
- SAT
1 stop14h 15m
Multiple Airlines
Deal found 7/31![Multiple Airlines logo]()
$390
This Southwest deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” 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 10/96:45 pm
SAT
- STL
1 stop5h 00m
Southwest
Tue 10/138:50 pm
STL
- SAT
Nonstop2h 10m
Southwest
Deal found 7/28![Southwest logo]()
$317
This United Airlines deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 8/152:15 pm
SAT
- PIA
2 stops8h 28m
United Airlines
Wed 8/193:35 pm
PIA
- SAT
1 stop7h 15m
United Airlines
Deal found 7/30![United Airlines logo]()
$384
This Delta deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/306:25 am
SAT
- MDW
1 stop5h 26m
Delta
Thu 9/1011:35 am
MDW
- SAT
1 stop5h 26m
Delta
Deal found 7/27![Delta logo]()
$395
This Kiwi.com deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” 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 10/159:25 am
SAT
- RFD
2 stops22h 34m
Multiple Airlines
Sun 10/189:33 pm
RFD
- SAT
1 stop14h 15m
Multiple Airlines
Deal found 7/28![Multiple Airlines logo]()
$417
This United Airlines deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 9/105:30 pm
SAT
- ORD
Nonstop2h 59m
United Airlines
Sat 9/128:45 am
ORD
- SAT
Nonstop3h 07m
United Airlines
Deal found 7/29![United Airlines logo]()
$387
This American Airlines deal was found by Cheapflights users on 8/1. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/92:00 pm
SAT
- BMI
2 stops10h 03m
American Airlines
Sun 9/134:24 pm
BMI
- SAT
1 stop6h 26m
American Airlines
Deal found 8/1![American Airlines logo]()
$389
Last-minute flights from San Antonio to IllinoisDiscover last-minute flight deals from San Antonio to Illinois. Data last updated August 1, 2026 and is based on user searches.
Discover last-minute flight deals from San Antonio to Illinois. Data last updated August 1, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Mon 8/109:32 pm
SAT
- ORD
1 stop8h 05m
Frontier
Thu 10/2910:40 pm
ORD
- SAT
1 stop11h 32m
Frontier
Deal found 7/29![Frontier logo]()
$279
This CheapOair deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 8/177:49 pm
SAT
- ORD
1 stop17h 47m
Frontier
Sat 8/222:41 pm
ORD
- SAT
1 stop28h 50m
Frontier
Deal found 7/30![Frontier logo]()
$269
This Trip.com deal was found by Cheapflights users on 7/31. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/1910:24 pm
SAT
- ORD
1 stop20h 38m
Frontier
Wed 8/262:41 pm
ORD
- SAT
1 stop28h 50m
Frontier
Deal found 7/31![Frontier logo]()
$276
This Super.com deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/208:26 pm
SAT
- ORD
1 stop17h 10m
Frontier
Fri 8/219:10 pm
ORD
- SAT
1 stop11h 46m
Frontier
Deal found 7/27![Frontier logo]()
$284
This Frontier deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2210:24 pm
SAT
- STL
1 stop19h 26m
Frontier
Mon 8/247:58 pm
STL
- SAT
1 stop23h 33m
Frontier
Deal found 7/27![Frontier logo]()
$241
This Trip.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Mon 8/2410:24 pm
SAT
- STL
1 stop19h 26m
Frontier
Thu 8/277:58 pm
STL
- SAT
1 stop23h 33m
Frontier
Deal found 7/29![Frontier logo]()
$263
This CheapOair deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/248:26 pm
SAT
- ORD
1 stop17h 10m
Frontier
Mon 8/318:11 pm
ORD
- SAT
1 stop25h 18m
Frontier
Deal found 7/27![Frontier logo]()
$273
This CheapOair deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/258:26 pm
SAT
- ORD
1 stop17h 10m
Frontier
Tue 9/12:41 pm
ORD
- SAT
1 stop28h 50m
Frontier
Deal found 7/27![Frontier logo]()
$283
This Kiwi.com deal was found by Cheapflights users on 7/31. 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.
Thu 8/2710:24 pm
SAT
- ORD
1 stop20h 38m
Frontier
Mon 8/311:59 pm
ORD
- SAT
2 stops29h 32m
Frontier
Deal found 7/31![Frontier logo]()
$271
This Trip.com deal was found by Cheapflights users on 7/31. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2710:24 pm
SAT
- ORD
1 stop20h 38m
Frontier
Sun 8/308:11 pm
ORD
- SAT
1 stop25h 18m
Frontier
Deal found 7/31![Frontier logo]()
$278
This Frontier deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/289:51 am
SAT
- ORD
1 stop13h 17m
Frontier
Fri 9/116:30 am
ORD
- SAT
1 stop12h 55m
Frontier
Deal found 7/27![Frontier logo]()
$272
This CheapOair deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/288:26 pm
SAT
- ORD
1 stop17h 10m
Frontier
Mon 9/78:11 pm
ORD
- SAT
1 stop25h 18m
Frontier
Deal found 7/27![Frontier logo]()
$275
One-way flights from San Antonio to IllinoisSearch for one-way flight options from San Antonio to Illinois. Find affordable one-way fares based on user searches. Data last updated August 1, 2026.
Search for one-way flight options from San Antonio to Illinois. Find affordable one-way fares based on user searches. Data last updated August 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/31. 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.
Tue 9/298:20 pm
SAT
- STL
1 stop22h 57m
Frontier
Deal found 7/31![Frontier logo]()
$95
This Frontier deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/229:51 am
SAT
- STL
1 stop6h 20m
Frontier
Deal found 7/30![Frontier logo]()
$104
This Trip.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Sat 9/128:20 pm
SAT
- STL
1 stop15h 47m
Frontier
Deal found 7/29![Frontier logo]()
$105
This Frontier deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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.
Mon 9/289:50 pm
SAT
- ORD
1 stop7h 48m
Frontier
Deal found 7/29![Frontier logo]()
$109
This Expedia deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 10/299:51 pm
SAT
- STL
1 stop24h 48m
Frontier
Deal found 7/30![Frontier logo]()
$110
This Kiwi.com deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” 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 8/268:26 pm
SAT
- STL
1 stop22h 47m
Frontier
Deal found 7/29![Frontier logo]()
$112
This Super.com deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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 8/299:51 am
SAT
- ORD
1 stop13h 17m
Frontier
Deal found 7/30![Frontier logo]()
$114
This Frontier deal was found by Cheapflights users on 7/31. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/299:51 am
SAT
- STL
1 stop6h 20m
Frontier
Deal found 7/31![Frontier logo]()
$115
This Frontier deal was found by Cheapflights users on 7/30. Clicking the “Pick Dates” 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.
Mon 8/319:51 am
SAT
- ORD
1 stop13h 17m
Frontier
Deal found 7/30![Frontier logo]()
$115
This Super.com deal was found by Cheapflights users on 7/31. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2710:24 pm
SAT
- ORD
1 stop20h 38m
Frontier
Deal found 7/31![Frontier logo]()
$116
This Super.com deal was found by Cheapflights users on 7/31. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/59:51 am
SAT
- ORD
1 stop13h 17m
Frontier
Deal found 7/31![Frontier logo]()
$117
This iWofly deal was found by Cheapflights users on 7/31. 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 iWofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/122:47 pm
SAT
- ORD
1 stop14h 51m
Frontier
Deal found 7/31![Frontier logo]()
$118
Find flight deals from San Antonio to Illinois
Keep the following information in mind while searching for San Antonio to Illinois flight deals. Data was last updated August 1, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $219 (Kiwi.com) |
One-way from | $95 (Kiwi.com) |
Popular in | June |
Cheapest in | September |
Average price | $366 |
Good round-trip deal | $329 or less |
Good one-way deal | $249 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from San Antonio 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 August 1, 2026.
Use the filters below to find and compare flights from San Antonio to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Wed 8/26
2:50 pm-5:25 pm
Nonstop2h 35m
Chicago Midway
Mon 8/31
11:05 am-1:40 pm
Nonstop2h 35m
$291
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Thu 10/1
9:20 am-12:00 pm
Nonstop2h 40m
Chicago Midway
Mon 10/5
9:20 pm-12:05 am
Nonstop2h 45m
$297
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Sat 10/10
3:45 pm-7:55 pm
1 stop4h 10m
Chicago Midway
Tue 10/13
8:45 pm-11:30 pm
Nonstop2h 45m
$301
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Thu 10/15
5:30 am-10:51 am
1 stop5h 21m
Lambert-St Louis
Mon 10/19
7:20 pm-12:33 am
1 stop5h 13m
$307
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Mon 9/21
3:30 pm-7:20 pm
1 stop3h 50m
Chicago Midway
Sat 10/3
10:40 am-5:00 pm
1 stop6h 20m
$312
San AntonioChicago
SAT - RFD
SATRFD
San Antonio
Tue 9/22
8:20 pm-3:03 pm
2 stops42h 43m
Chicago Greater Rockford
Thu 10/1
9:03 pm-11:44 am
1 stop14h 41m
$314
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Sat 8/29
5:15 am-12:39 pm
1 stop7h 24m
Chicago Midway
Wed 9/9
5:37 pm-10:44 pm
1 stop5h 07m
$317
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Mon 9/21
4:21 pm-10:44 pm
1 stop6h 23m
Chicago Midway
Thu 9/24
2:00 pm-9:22 pm
1 stop7h 22m
$317
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Fri 9/4
2:55 pm-9:45 pm
1 stop6h 50m
Lambert-St Louis
Sun 9/6
8:05 pm-10:15 pm
Nonstop2h 10m
$317
Quickest round-trip
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Fri 8/28
3:30 pm-5:40 pm
Nonstop2h 10m
Lambert-St Louis
Fri 9/4
8:45 pm-11:00 pm
Nonstop2h 15m
$317
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from San Antonio to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from San Antonio with our price prediction graph.
SAT-STL
SAT-ORD
SAT-MDW
SAT-RFD
SAT-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 Antonio to Illinois
SAT-USIL
SAT-STL
SAT-ORD
SAT-MDW
SAT-RFD
What is the cheapest month to book a flight from San Antonio to Illinois?
Currently, September is the cheapest month in which you can book a flight from San Antonio to Illinois (average of $336). Flying from San Antonio to Illinois in June is currently the most expensive (average of $439). 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 SAT to IL?
Find hourly flight availability from San Antonio 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 August 1, 2026.
It’s optimal to fly from San Antonio to Illinois in the evening. By choosing this option you can save up to 34% on the cost of your flight, compared to a flight at noon.
Weekly flight availability from San Antonio to Illinois
Explore weekly flight availability from San Antonio 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 August 1, 2026.
The most flights from SAT to USIL are scheduled on a Thursday (28 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (13 on average).
How much does it cost to fly round-trip from San Antonio to Illinois?
Airfare is typical for this route at the moment.
San Antonio to Illinois flights typically cost between $235 and $408 in September.The cheapest round-trip price found within the last 5 days was $268 on Frontier (Sep 14-Sep 16).
How far ahead should I book a flight from San Antonio to Illinois?
Booking 69 days in advance of your planned departure date is, on average, the best time to get cheap flights from San Antonio to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
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 August 1, 2026.
Read through reviews of airlines operating flights from San Antonio to Illinois, such as Southwest,Delta, andUnited Airlines. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Crew
8.6
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Overall
8.0
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 Antonio 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 Antonio to Illinois
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Complete your trip
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Search flights from San Antonio to Illinois by cabin class
Find flights from San Antonio to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
San Antonio and Illinois flights
Browse other San Antonio and Illinois flight options. Last updated on August 1, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
San Antonio to Illinois flights
Consider these flights traveling from San Antonio to Illinois.
Top 5 airlines flying from San Antonio to Illinois
Discover the top 5 airlines that operate flights from San Antonio 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 August 1, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$97 | Average$223 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$235 | Average$431 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$279 | Average$441 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$287 | Average$441 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$306 | Average$323 | FlexibilityNo cancel fee | On-timeN/A |