$65+ 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 6/16. Fares are subject to change and may not be available on all flights or dates of travel.
SAT — ORD
May 18 — May 251
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 April 18, 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 April 18, 2026.
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/97:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Mon 5/119:18 pm
STL
- SAT
1 stop22h 56m
Frontier
Deal found 4/14![Frontier logo]()
$140
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/107:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Fri 5/159:18 pm
STL
- SAT
1 stop22h 56m
Frontier
Deal found 4/14![Frontier logo]()
$151
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/46:31 pm
SAT
- STL
1 stop23h 35m
Frontier
Thu 5/712:36 pm
STL
- SAT
1 stop7h 38m
Frontier
Deal found 4/14![Frontier logo]()
$171
This Frontier deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/3012:46 pm
SAT
- STL
1 stop8h 14m
Frontier
Thu 5/712:36 pm
STL
- SAT
1 stop7h 38m
Frontier
Deal found 4/13![Frontier logo]()
$181
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/58:59 pm
SAT
- STL
1 stop20h 35m
Frontier
Sun 6/78:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/13![Frontier logo]()
$191
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/97:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Wed 5/136:51 pm
STL
- SAT
1 stop25h 23m
Frontier
Deal found 4/13![Frontier logo]()
$192
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/267:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Mon 6/19:21 pm
STL
- SAT
1 stop22h 53m
Frontier
Deal found 4/13![Frontier logo]()
$196
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/87:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Tue 5/126:51 pm
STL
- SAT
2 stops24h 08m
Frontier
Deal found 4/13![Frontier logo]()
$200
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/117:54 pm
SAT
- STL
2 stops22h 12m
Frontier
Fri 5/158:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/14![Frontier logo]()
$211
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/287:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Sun 5/319:06 pm
STL
- SAT
1 stop23h 08m
Frontier
Deal found 4/14![Frontier logo]()
$212
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:54 pm
SAT
- STL
2 stops13h 01m
Frontier
Thu 5/78:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/13![Frontier logo]()
$216
This American Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” 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 6/106:28 pm
SAT
- MLI
1 stop5h 24m
American Airlines
Tue 6/166:56 pm
MLI
- SAT
1 stop5h 09m
American Airlines
Deal found 4/16![American Airlines logo]()
$273
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 April 18, 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 April 18, 2026.
This American Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” 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 6/106:28 pm
SAT
- MLI
1 stop5h 24m
American Airlines
Tue 6/166:56 pm
MLI
- SAT
1 stop5h 09m
American Airlines
Deal found 4/16![American Airlines logo]()
$273
This United Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:49 am
SAT
- ORD
Nonstop2h 56m
United Airlines
Wed 5/207:45 pm
ORD
- SAT
Nonstop3h 09m
United Airlines
Deal found 4/15![United Airlines logo]()
$297
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/135:40 pm
SAT
- MDW
1 stop4h 05m
Southwest
Mon 5/189:40 pm
MDW
- SAT
Nonstop2h 50m
Southwest
Deal found 4/15![Southwest logo]()
$309
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/127:55 am
SAT
- MDW
1 stop8h 17m
Delta
Tue 5/199:22 am
MDW
- SAT
1 stop6h 30m
Delta
Deal found 4/13![Delta logo]()
$317
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/138:59 pm
SAT
- RFD
1 stop15h 01m
Multiple Airlines
Mon 5/188:35 pm
RFD
- SAT
2 stops46h 24m
Multiple Airlines
Deal found 4/14![Multiple Airlines logo]()
$368
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/107:25 am
SAT
- STL
Nonstop2h 10m
Southwest
Fri 6/126:45 pm
STL
- SAT
1 stop6h 05m
Southwest
Deal found 4/15![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/22:27 pm
SAT
- MDW
1 stop6h 42m
Delta
Thu 6/41:59 pm
MDW
- SAT
1 stop7h 33m
Delta
Deal found 4/13![Delta logo]()
$323
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/106:40 am
SAT
- MLI
1 stop5h 59m
United Airlines
Tue 6/162:31 pm
MLI
- SAT
2 stops8h 11m
United Airlines
Deal found 4/14![United Airlines logo]()
$338
This American Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” 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 5/23:11 pm
SAT
- BMI
1 stop7h 16m
American Airlines
Wed 5/65:00 am
BMI
- SAT
2 stops9h 21m
American Airlines
Deal found 4/17![American Airlines logo]()
$344
This Southwest deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/306:25 pm
SAT
- STL
1 stop4h 00m
Southwest
Tue 6/28:25 am
STL
- SAT
Nonstop2h 20m
Southwest
Deal found 4/17![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” 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 5/166:50 am
SAT
- STL
1 stop8h 01m
Delta
Sat 5/237:05 pm
STL
- SAT
1 stop5h 39m
Delta
Deal found 4/17![Delta logo]()
$327
This United Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/195:34 pm
SAT
- ORD
Nonstop3h 02m
United Airlines
Sun 5/242:33 pm
ORD
- SAT
1 stop6h 21m
United Airlines
Deal found 4/13![United Airlines logo]()
$342
This Kiwi.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” 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 5/219:55 am
SAT
- RFD
2 stops21h 50m
Multiple Airlines
Sun 5/2411:27 am
RFD
- SAT
1 stop28h 49m
Multiple Airlines
Deal found 4/16![Multiple Airlines logo]()
$381
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/75:25 am
SAT
- MDW
1 stop6h 31m
Delta
Thu 5/146:23 am
MDW
- SAT
1 stop7h 09m
Delta
Deal found 4/13![Delta logo]()
$329
This United Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/266:40 am
SAT
- STL
1 stop5h 31m
United Airlines
Tue 5/264:48 pm
STL
- SAT
1 stop7h 11m
United Airlines
Deal found 4/13![United Airlines logo]()
$346
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/217:20 am
SAT
- STL
Nonstop2h 10m
Southwest
Tue 5/268:55 pm
STL
- SAT
Nonstop2h 20m
Southwest
Deal found 4/16![Southwest logo]()
$346
This American Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/135:00 am
SAT
- BMI
2 stops9h 16m
American Airlines
Wed 5/2011:16 am
BMI
- SAT
1 stop6h 28m
American Airlines
Deal found 4/15![American Airlines logo]()
$395
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/24:20 pm
SAT
- MLI
1 stop6h 15m
Delta
Sun 5/105:17 pm
MLI
- SAT
1 stop5h 14m
Delta
Deal found 4/15![Delta logo]()
$336
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/296:40 am
SAT
- CMI
1 stop6h 10m
United Airlines
Wed 9/25:45 am
CMI
- SAT
1 stop6h 26m
United Airlines
Deal found 4/14![United Airlines logo]()
$350
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/96:05 am
SAT
- STL
1 stop7h 15m
Southwest
Mon 5/119:45 pm
STL
- SAT
Nonstop2h 20m
Southwest
Deal found 4/15![Southwest logo]()
$356
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/166:50 am
SAT
- STL
1 stop8h 01m
Delta
Wed 5/201:27 pm
STL
- SAT
1 stop7h 19m
Delta
Deal found 4/13![Delta logo]()
$351
This United Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/157:10 pm
SAT
- ORD
1 stop5h 35m
United Airlines
Mon 5/187:45 pm
ORD
- SAT
Nonstop3h 09m
United Airlines
Deal found 4/15![United Airlines logo]()
$353
This Southwest deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/144:25 pm
SAT
- MDW
1 stop4h 35m
Southwest
Mon 5/186:15 pm
MDW
- SAT
1 stop6h 00m
Southwest
Deal found 4/14![Southwest logo]()
$363
This American Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/134:28 pm
SAT
- PIA
2 stops7h 09m
American Airlines
Mon 5/185:40 pm
PIA
- SAT
1 stop14h 43m
American Airlines
Deal found 4/14![American Airlines logo]()
$454
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/178:56 pm
SAT
- RFD
1 stop15h 27m
Multiple Airlines
Sun 6/219:19 am
RFD
- SAT
2 stops30h 18m
Multiple Airlines
Deal found 4/14![Multiple Airlines logo]()
$507
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” 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 6/236:45 am
SAT
- ORD
1 stop7h 31m
Delta
Mon 7/65:40 pm
ORD
- SAT
1 stop6h 50m
Delta
Deal found 4/16![Delta logo]()
$352
This United Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/156:49 am
SAT
- ORD
Nonstop2h 56m
United Airlines
Tue 5/197:45 pm
ORD
- SAT
Nonstop3h 09m
United Airlines
Deal found 4/15![United Airlines logo]()
$357
This Southwest deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/77:45 pm
SAT
- MDW
1 stop4h 10m
Southwest
Thu 5/1412:45 pm
MDW
- SAT
2 stops6h 25m
Southwest
Deal found 4/13![Southwest logo]()
$363
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/1110:47 am
SAT
- MLI
1 stop5h 50m
Delta
Tue 6/165:17 pm
MLI
- SAT
1 stop7h 13m
Delta
Deal found 4/16![Delta logo]()
$355
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/135:34 pm
SAT
- PIA
1 stop5h 15m
United Airlines
Mon 5/185:30 pm
PIA
- SAT
1 stop5h 24m
United Airlines
Deal found 4/14![United Airlines logo]()
$367
Last-minute flights from San Antonio to IllinoisDiscover last-minute flight deals from San Antonio to Illinois. Data last updated April 18, 2026 and is based on user searches.
Discover last-minute flight deals from San Antonio to Illinois. Data last updated April 18, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/3012:46 pm
SAT
- STL
1 stop8h 14m
Frontier
Thu 5/712:36 pm
STL
- SAT
1 stop7h 38m
Frontier
Deal found 4/13![Frontier logo]()
$181
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/46:31 pm
SAT
- STL
1 stop23h 35m
Frontier
Thu 5/712:36 pm
STL
- SAT
1 stop7h 38m
Frontier
Deal found 4/14![Frontier logo]()
$171
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:54 pm
SAT
- STL
2 stops13h 01m
Frontier
Thu 5/78:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/13![Frontier logo]()
$216
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/87:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Tue 5/126:51 pm
STL
- SAT
2 stops24h 08m
Frontier
Deal found 4/13![Frontier logo]()
$200
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/97:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Mon 5/119:18 pm
STL
- SAT
1 stop22h 56m
Frontier
Deal found 4/14![Frontier logo]()
$140
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/97:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Wed 5/136:51 pm
STL
- SAT
1 stop25h 23m
Frontier
Deal found 4/13![Frontier logo]()
$192
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/107:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Fri 5/159:18 pm
STL
- SAT
1 stop22h 56m
Frontier
Deal found 4/14![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/117:54 pm
SAT
- STL
2 stops22h 12m
Frontier
Fri 5/158:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/14![Frontier logo]()
$211
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/137:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Sat 5/168:08 pm
STL
- SAT
1 stop22h 51m
Frontier
Deal found 4/14![Frontier logo]()
$191
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/267:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Mon 6/19:21 pm
STL
- SAT
1 stop22h 53m
Frontier
Deal found 4/13![Frontier logo]()
$196
This Kiwi.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:54 pm
SAT
- ORD
1 stop24h 38m
Multiple Airlines
Sun 5/318:05 am
ORD
- SAT
1 stop8h 11m
Multiple Airlines
Deal found 4/16![Multiple Airlines logo]()
$280
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/287:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Sun 5/319:06 pm
STL
- SAT
1 stop23h 08m
Frontier
Deal found 4/14![Frontier logo]()
$212
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 April 18, 2026.
Search for one-way flight options from San Antonio to Illinois. Find affordable one-way fares based on user searches. Data last updated April 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/167:51 pm
SAT
- STL
1 stop23h 32m
Frontier
Deal found 4/14![Frontier logo]()
$65
This Kiwi.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/137:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Deal found 4/15![Frontier logo]()
$72
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/58:59 pm
SAT
- STL
1 stop21h 07m
Frontier
Deal found 4/14![Frontier logo]()
$77
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/157:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Deal found 4/14![Frontier logo]()
$95
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/198:59 pm
SAT
- STL
1 stop21h 07m
Frontier
Deal found 4/14![Frontier logo]()
$97
This Trip.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/46:31 pm
SAT
- STL
1 stop23h 35m
Frontier
Deal found 4/15![Frontier logo]()
$99
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/167:54 pm
SAT
- STL
1 stop23h 29m
Frontier
Deal found 4/14![Frontier logo]()
$100
This Trip.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/24:04 pm
SAT
- STL
1 stop27h 17m
Frontier
Deal found 4/15![Frontier logo]()
$101
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/127:54 pm
SAT
- STL
2 stops13h 01m
Frontier
Deal found 4/13![Frontier logo]()
$109
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/167:54 pm
SAT
- ORD
2 stops27h 07m
Frontier
Deal found 4/13![Frontier logo]()
$139
This Kiwi.com deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/167:51 pm
SAT
- ORD
2 stops24h 02m
Frontier
Deal found 4/17![Frontier logo]()
$141
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/157:54 pm
SAT
- MDW
2 stops42h 18m
Frontier
Deal found 4/14![Frontier logo]()
$141
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 April 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $140 (Frontier) |
One-way from | $65 (Kiwi.com) |
Popular in | December |
Cheapest in | September |
Average price | $365 |
Good round-trip deal | $387 or less |
Good one-way deal | $208 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 April 18, 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 AntonioMoline
SAT - MLI
SATMLI
San Antonio
Wed 6/10
6:28 pm-11:52 pm
1 stop5h 24m
Moline Quad-City
Tue 6/16
6:56 pm-12:05 am
1 stop5h 09m
$273
San AntonioChicago
SAT - ORD
SATORD
San Antonio
Wed 5/13
6:49 am-9:45 am
Nonstop2h 56m
Chicago O'Hare Intl
Wed 5/20
7:45 pm-10:54 pm
Nonstop3h 09m
$297
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Wed 5/13
5:40 pm-9:45 pm
1 stop4h 05m
Chicago Midway
Mon 5/18
9:40 pm-12:30 am
Nonstop2h 50m
$309
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Tue 5/12
7:55 am-4:12 pm
1 stop8h 17m
Chicago Midway
Tue 5/19
9:22 am-3:52 pm
1 stop6h 30m
$317
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Wed 6/10
7:25 am-9:35 am
Nonstop2h 10m
Lambert-St Louis
Fri 6/12
6:45 pm-12:50 am
1 stop6h 05m
$317
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Sat 5/30
6:25 pm-10:25 pm
1 stop4h 00m
Lambert-St Louis
Tue 6/2
8:25 am-10:45 am
Nonstop2h 20m
$317
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Tue 6/2
2:27 pm-9:09 pm
1 stop6h 42m
Chicago Midway
Thu 6/4
1:59 pm-9:32 pm
1 stop7h 33m
$323
San AntonioSt. Louis
SAT - STL
SATSTL
San Antonio
Sat 5/16
6:50 am-2:51 pm
1 stop8h 01m
Lambert-St Louis
Sat 5/23
7:05 pm-12:44 am
1 stop5h 39m
$327
San AntonioChicago
SAT - MDW
SATMDW
San Antonio
Thu 5/7
5:25 am-11:56 am
1 stop6h 31m
Chicago Midway
Thu 5/14
6:23 am-1:32 pm
1 stop7h 09m
$329
San AntonioMoline
SAT - MLI
SATMLI
San Antonio
Sat 5/2
4:20 pm-10:35 pm
1 stop6h 15m
Moline Quad-City
Sun 5/10
5:17 pm-10:31 pm
1 stop5h 14m
$336
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-MLI
SAT-ORD
SAT-MDW
SAT-RFD
SAT-STL
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-MLI
SAT-ORD
SAT-MDW
SAT-RFD
What is the cheapest month to book a flight from San Antonio to Illinois?
Currently, August is the cheapest month in which you can book a flight from San Antonio to Illinois (average of $96). Flying from San Antonio to Illinois in June is currently the most expensive (average of $218). 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 April 18, 2026.
It’s optimal to fly from San Antonio to Illinois in the morning. By choosing this option you can save up to 40% on the cost of your flight, compared to a flight in the evening.
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 April 18, 2026.
The most flights from SAT to USIL are scheduled on a Friday (30 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (20 on average).
How much does it cost to fly round-trip from San Antonio to Illinois?
Reviews of airlines servicing Illinois
Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated April 18, 2026.
Read through reviews of airlines operating flights from San Antonio to Illinois, such as Southwest,United Airlines, andAmerican 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
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Crew
8.6
Food
7.0
Comfort
8.0
Overall
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
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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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 April 18, 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 April 18, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$96 | Average$213 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$143 | Average$261 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$218 | Average$417 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$247 | Average$403 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$256 | Average$400 | FlexibilityNo cancel fee | On-time63% |