$88 Find Cheap Flights from San Antonio to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from San Antonio to Illinois departing on 3/24. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Antonio to Illinois, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Antonio to Illinois, as well as popular online travel agencies
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Flight Deals

Cheap Flights from San Antonio to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$207
Moline
Moline1 stop$319
Bloomington
Bloomington2 stops$350
Champaign
Champaign1 stop$572
Springfield
Springfield2 stops$538
St. Louis
St. Louis1 stop$175
Chicago
Chicago1 stop$207
Moline
Moline1 stop$319
Bloomington
Bloomington2 stops$350
Champaign
Champaign1 stop$572
Springfield
Springfield2 stops$538
St. Louis
St. Louis1 stop$175

Book Cheap San Antonio to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from San Antonio to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from San Antonio to Illinois

Thu, Apr 2 - Fri, Apr 3
Frontier Logo
6:45 am - 9:48 am
SAT
-
STL
27h 03m
1 stop
Frontier Logo
8:16 pm - 12:19 am
STL
-
SAT
28h 03m
1 stop
$175Frontier
Thu, Apr 9 - Sat, Apr 11
Frontier Logo
6:45 am - 9:48 am
SAT
-
STL
27h 03m
1 stop
Frontier Logo
8:16 pm - 12:19 am
STL
-
SAT
28h 03m
1 stop
$180Frontier
Wed, Apr 8 - Fri, Apr 10
Multiple Airlines Logo
10:22 am - 5:15 pm
SAT
-
ORD
6h 53m
1 stop
Multiple Airlines Logo
2:29 pm - 12:19 am
ORD
-
SAT
9h 50m
1 stop
$225Multiple Airlines
Tue, May 5 - Tue, May 19
Multiple Airlines Logo
7:54 pm - 9:55 am
SAT
-
ORD
38h 01m
2 stops
Multiple Airlines Logo
9:42 pm - 6:59 pm
ORD
-
SAT
21h 17m
1 stop
$243Multiple Airlines
Wed, Apr 8 - Wed, Apr 15
Southwest Logo
2:35 pm - 5:10 pm
SAT
-
MDW
2h 35mnonstop
Southwest Logo
9:00 pm - 11:50 pm
MDW
-
SAT
2h 50mnonstop
$297Southwest
Wed, Apr 8 - Wed, Apr 15
Southwest Logo
5:40 pm - 9:45 pm
SAT
-
MDW
4h 05m
1 stop
Southwest Logo
9:00 pm - 11:50 pm
MDW
-
SAT
2h 50mnonstop
$303Southwest
Sat, May 2 - Sat, May 9
American Airlines Logo
6:26 am - 12:21 pm
SAT
-
MLI
5h 55m
1 stop
American Airlines Logo
12:52 pm - 8:47 pm
MLI
-
SAT
7h 55m
1 stop
$319American Airlines
Tue, May 19 - Tue, Jun 2
United Airlines Logo
2:00 pm - 6:59 pm
SAT
-
PIA
4h 59m
1 stop
United Airlines Logo
8:20 am - 4:03 pm
PIA
-
SAT
7h 43m
1 stop
$319United Airlines
Sat, May 2 - Sat, May 9
American Airlines Logo
4:28 pm - 11:54 pm
SAT
-
MLI
7h 26m
2 stops
American Airlines Logo
12:04 pm - 5:41 pm
MLI
-
SAT
5h 37m
1 stop
$324American Airlines
Tue, May 19 - Tue, Jun 2
United Airlines Logo
5:30 am - 12:57 pm
SAT
-
PIA
7h 27m
2 stops
United Airlines Logo
5:33 pm - 10:57 pm
PIA
-
SAT
5h 24m
1 stop
$324United Airlines
Booking Insights

KAYAK's insights & trends for San Antonio to Illinois flights

Get data-powered insights and trends into flights from San Antonio to Illinois to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest San Antonio to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from San Antonio found in the last 72 hours was to Chicago, at $274 round-trip. The most popular route is from San Antonio (SAT) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $274.

What is the cheapest time of day to fly to Illinois?

The average price for all round-trip flights from San Antonio to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Illinois is generally in the morning, when round-trip flights cost $470 on average. Morning departures are around 29% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $816.

Can I save money by flying with a layover from San Antonio to Illinois?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $380, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from San Antonio to Illinois?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from San Antonio to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from San Antonio to Illinois is September, when tickets cost $305 (return) on average. On the other hand, the most expensive months are December and March, when the average cost of round-trip tickets is $404 and $393 respectively.

What’s the cheapest day of the week to fly from San Antonio to Illinois?

The average price of all round-trip flights from San Antonio to Illinois clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Illinois on a Thursday, as we generally find the cheapest rates on that day for this route. On the other hand, Sunday is the most expensive day to fly from San Antonio to Illinois. For your return ticket, we recommend flying on a Tuesday and avoiding Sundays for the best deals.

How far in advance should I book a flight from San Antonio to Illinois?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from San Antonio to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from San Antonio to Illinois, you should book around 4 weeks before departure, which saves you about 48% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 14 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$80
Best time to beat the crowds but there is an average 9% increase in price.
Most popular time to fly and prices are also 12% lower on average.
Flight from San Antonio to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from San Antonio to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from San Antonio to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from San Antonio to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from San Antonio to Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from San Antonio to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from San Antonio to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from San Antonio to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from San Antonio to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top tips for finding cheap flights to Illinois

  • Looking for a cheap flight? 25% of our users found tickets from San Antonio to the following destinations at these prices or less: Chicago $199 one-way - $390 round-trip

Reviews of the top 5 airlines serving from San Antonio to Illinois

 
See real verified KAYAK customer reviews for airlines flying from San Antonio to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from San Antonio to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4318 reviews
8.1Boarding
8.6Crew
7.5Entertainment
8.0Comfort
7.0Food
Airline reviews

I elected to pay for the upgrades and found very little difference

6.0 GoodChris, Mar 2026
DAL - SAT
Read more Southwest reviews

I elected to pay for the upgrades and found very little difference

WiFi was not working and didn’t have a beverage service

Flight was hours late, unable to sit next to spouse, I have had so much better experiences. Substantially better, only saving grace was that it was a short flight.

I was assigned seat 7E, yet my boarding was Group 5, which caused me to have to put my luggage in the back of the plance above `19 or 20 aisle, as passengers who had boarded earlier took the overhead bins in the front. SW needs to monitor bin space and ensure that bin space above the seat are aligned to those sitting near their seats. Also the seating assignments needs to align with group number. Maybe board those last first and so on? Having said the ALL the passengers on the plane were gracious enough to allow me and other passengers in this dilema to retrieve our luggage and helped us along the way. I always love the flight staff, as always their fantastic and I can't rave about them enough!

All good except once again bags took an hour at Midway Airport Happens all the time. Ridiculous

Great vacation. Can't wait till next year for another one.

The seats were comfortable, and the boarding process was pretty smooth.

The flight crew was extremely rude and especially not helpful when our flight was delayed.

Check-in, Boarding and flight were smooth. All the employees and crew was very nice and funny. They gave the kids crayons and workbooks to keep them occupied which was a big win. I’ve flown Southwest many times and that’s the first time I’ve seen that and it is a great addition.

Still a fan of open seating. Flight was on schedule and arrived on time. The 737 MAX is very comfortable.

Wonderful. Quick boarding. Early departure and we arrived 30 minutes early at our destination. Unfortunately, when you arrive early, there is still a departing aircraft at our gate. We had to park for 30 minutes until the gate was clear. So our early arrival was not really early at the gate. Otherwise it was a quick and smooth flight. Appreciated the efficiency.

Do not like the size of the overhead bin. I think staff should monitor the size of suitcases that are being carried on by passengers to ensure they meet the size requirement.

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

United Airlines is my preferred airlines and I am thankful for Gary who also help support me on the phone to switch my flight literally last min.

Seated dude next to me even though lots of empty rows. But main thing was we sat on the tarmac after landing for 30 minutes because of, in the words of the dude who sat next to me, “operational incompetence”. We got changing directions about where to pick up gate checked bags. Pilot and flight attendant were awesome though.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

Perfect flight. Smooth flight. Arrived 20 minutes early at destination. Excellent service.

The flights were on time which was great give. It was holiday travel season and there’d been some weather issues. The only complaint and this is every time with United is the terrible seat design. The head rest is not built for comfort and having my neck bent forward for a cross country trip reminded me while I try not to take United flights as a rule.

Everything was absolutely wonderful from check in to baggage claim. Staff was very professional and sweet. Will definitely recommend United to family and friends.

They did the one thing that really matters - got to Chicago early.

There was no inflight service. Once we landed we were delayed to find a gate for an hour and a half which was 1/2 the total time in the air.

The chicken wrap was tiny ($13 for what looked like a 1/3 of a normal wrap?) and disgusting.

It was good experience this time. The flight was on time.

There was a delay with the plan which cause the flight to leave later and once arrived in Chicago there was another delay and some passengers missed their connecting flights

The gate agent had a really bad attitude and refused to help me get on the standby list. She just handed me a card and said I needed to call a number. I asked her to help with the AA app on my phone and she just shrugged and said she didnt know. After a few phone calls, I eventually just went to a different gate agent on the other side of the terminal and got the help I needed.

Overall, my last three trips on American Airlines have all been either delayed or "rescheduled" due to mechanical issues. At least on delay caused me to miss two possible connecting flights each later than the first. My last option for my last connection required the assistance of the onsite service desk (O'Hare Airport). The wait time for the service desk was such that it jeopardized getting booked on the last connecting flight available for the night. Suffice it to say, my latest experiences with American Airlines have caused me extensive loss of productive business and personal time and can therefore be classified as significantly less than satisfactory.

Waiting for gate in RDU for more than 20mins is crazy.

American Airlines was great and worked very hard to change my ticket so I could get an earlier, direct flight back to Dallas. However, I was informed that Kayak made mistakes with my itinerary and classified my ticket as desiring to be on the earlier flight instead of taking the necessary step of calling AA to get me on the standby list. This ended up keeping me from being added to the standby list and delayed me getting home by 6 hours. I am happy to discuss this further with Kayak so they can correct their procedures so this won't happen again.

Waited for oxygen tanks for 30 minutes after boarding was complete.

We flew in first class. The crew did not offer drinks before the flight took off, but they treated us well during the flight. The food was excellent. There was actually too much food served, but it was nice to have all the options.

If there are delays, it takes less than a minute for a Spirit employee to make an announcement. It’s very simple.

For a change, friendly staff at check-in and in flight.

Delayed both in takeoff and landing, trash plane no amenities, I've said it before but I'll never fly Spirit again.

It’s was a cheap flight and they got us there safely. It’s just their whole business model that make the experience “meh.” They make you paranoid about whether your personal item is too big. They make you paranoid about being crammed into a middle seat at the back of the plane. They purposely cram people together leaving multiple rows completely empty and even after the door closes the FA’s announce that everyone has to sit in their assigned seat. We knew what we were buying and in that regard we got a cheap and safe flight but it felt like they do their best to take any enjoyment out of the experience. That’s all on management, not the crew.

The flight was delayed for unknown reasons while other airlines weren’t. It was very frustrating.

Everything was good. On time, boarding fast, flight attendants friendly.

Spirit has always and will always stink. Absolute worst airline around.

Not seat assigned because overbooking. We could go because some people decided to give their seats.

The flights were very uncomfortable the seats don't have much leg room at all and they are pretty hard as well.

spirit delayed my first flight 9 hours and then cancelled my flight back home. Very disappointed with their service.

My flight was originally from SAT to MCO connecting from MCO to ORD. We got diverted to ATL and than Frontier staff there was sooo un helpful first they said they couldn’t give us any accommodation since our flight first got delayed that cancelled and now it’s 221am and I am still in ATL since they said they need to create a new flight my final destination is ORD and I have been delayed twice and cancelled. With no real help the frontier app didn’t work no email updates over all such a horrible experience

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

Remind customers of the need to have passport or new ID for boarding.

Flight was canceled. Most upsetting was message from Kayak, stating that the flight was canceled and click with Kayak for details regarding rebook, refund details. THERE'S NO INFORMATION PROVIDED BY KAYAK EXCEPT THAT FLIGHT IS CANCELED. AND NOW THIS SURVEY TO FIND OUT HOW WAS THE FLIGHT !!!!!!!

The flight never took off and we spent 7 hours at the airport

Gate not determined until I got to the airport - hard to plan the trip to the airport.

Our flight was canceled. I will never use Kayak nor Frontier for travel again. The entire experience was a headache.

Frontier.. nickel and dime add-ons. Flight late, on time, late again, last minute gate change, arrival gate required a shuttle to the terminal. They sure keep you guessing.. if you like a little chaos and airport anxiety, this is the airline for you!

This is my second time flying with Frontier. My current experience was very favorable. The staff from the gate to the plane was friendly, warm and professional. The food options lacked in my opinion. This area needs some attention in my opinion.

There was no food and no entertainment, so I'm not sure why these are even in the survey, as my understanding is frontier does not ever offer food without a few, not even a snack, and there are no screens so unless the flight safety talk is our entertainment why ask how we liked it?. One of the flight attendants say in the back of the plane as people filed in to their seats, yelling orders about where to put baggage and telling people to hurry up. It was the least professional experience I've ever had on a flight.

Everything you need to know for your flight from San Antonio to Illinois

Information on your arrival and departure airports