$64 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 3/4. 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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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$204
Moline
Moline1 stop$309
Champaign
Champaign1 stop$537
St. Louis
St. Louis1 stop$149
Chicago
Chicago1 stop$204
Moline
Moline1 stop$309
Champaign
Champaign1 stop$537
St. Louis
St. Louis1 stop$149

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

Mon, Feb 23 - Wed, Feb 25
Frontier Logo
1:57 pm - 11:59 pm
SAT
-
STL
10h 02m
1 stop
Frontier Logo
3:49 pm - 1:12 pm
STL
-
SAT
21h 23m
1 stop
$149Frontier
Tue, Feb 24 - Wed, Mar 4
Frontier Logo
5:36 pm - 3:53 pm
SAT
-
STL
22h 17m
1 stop
Frontier Logo
5:18 pm - 7:30 pm
STL
-
SAT
26h 12m
1 stop
$155Frontier
Sun, Feb 22 - Wed, Feb 25
Multiple Airlines Logo
5:04 pm - 6:51 am
SAT
-
STL
13h 47m
1 stop
Multiple Airlines Logo
3:49 pm - 11:59 pm
STL
-
SAT
8h 10m
1 stop
$161Multiple Airlines
Tue, Feb 24 - Tue, Mar 3
Multiple Airlines Logo
5:36 pm - 3:53 pm
SAT
-
STL
22h 17m
1 stop
Multiple Airlines Logo
3:49 pm - 11:59 pm
STL
-
SAT
8h 10m
1 stop
$164Multiple Airlines
Wed, Feb 18 - Sun, Feb 22
Spirit Airlines Logo
10:26 am - 11:22 am
SAT
-
ORD
24h 56m
1 stop
Spirit Airlines Logo
5:15 am - 9:30 am
ORD
-
SAT
28h 15m
1 stop
$206Spirit Airlines
Tue, Apr 7 - Sun, Apr 12
Spirit Airlines Logo
10:27 am - 11:21 am
SAT
-
ORD
24h 54m
1 stop
Spirit Airlines Logo
8:41 pm - 9:32 am
ORD
-
SAT
12h 51m
1 stop
$207Spirit Airlines
Sat, Feb 21 - Sat, Mar 7
United Airlines Logo
7:00 am - 12:43 pm
SAT
-
PIA
5h 43m
1 stop
United Airlines Logo
5:25 pm - 11:15 pm
PIA
-
SAT
5h 50m
1 stop
$279United Airlines
Sat, Feb 21 - Sat, Mar 7
United Airlines Logo
7:00 am - 12:43 pm
SAT
-
PIA
5h 43m
1 stop
United Airlines Logo
1:25 pm - 10:57 pm
PIA
-
SAT
9h 32m
2 stops
$284United Airlines
Sat, Feb 21 - Sat, Mar 7
American Airlines Logo
5:00 am - 2:17 pm
SAT
-
PIA
9h 17m
2 stops
American Airlines Logo
2:50 pm - 10:54 pm
PIA
-
SAT
8h 04m
2 stops
$289American Airlines
Thu, Feb 12 - Mon, Feb 16
American Airlines Logo
5:00 am - 1:00 pm
SAT
-
MLI
8h 00m
2 stops
American Airlines Logo
12:36 pm - 8:50 pm
MLI
-
SAT
8h 14m
1 stop
$380American 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 $288 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 $288.

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 $362, 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 March and December, when the average cost of round-trip tickets is $420 and $404 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 42% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 14 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$62
Best time to beat the crowds with an average 4% drop in price.
Most popular time to fly and prices are also 11% 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.

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

    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 31% 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 $860.

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 $236 one-way - $430 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 4267 reviews
8.1Boarding
7.0Food
8.0Comfort
8.6Crew
7.5Entertainment
Airline reviews

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

10.0 ExcellentAnonymous, Jan 2026
PHX - MDW
Read more Southwest reviews

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.

It was rough. The staff was unprofessional, the choice of on board drinks terrible, it was cramped in space at every airport, they always ran out of overhead bin space so they pressured people to check bags for free or we couldn’t leave on the plane— so I did check my bag to help, and they nearly lost my bag. My bag did not arrive on the luggage belt, another man on my flight and I had to waste our time going to the baggage office to search for our bags. I would only fly southwest again if it was my last choice. Also, my flights were consistently delayed over and over again— at one point they straight up told us we were waiting for the pilot to arrive.

Had to get off plane from prior flight even though I had to reboard same plane to continue to my final destination.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

Excellent. Would encourage Southwest to keep current boarding procedures with free style seating. Makes for a fantastic experience

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.

The flight was on time. I generally don’t drink or eat on short flights and the seats were good and the flight attendants were friendly. That’s all I expect

It was nice to have gotten up upgraded to first class with a meal on a three hour flight

Very bad! They kept delaying my flight and wouldn’t do anything about it

Door to door, the crew and staff were amazing. It was a stressful travel day with delays, but they were focused on customers and doing what they could to get us to our destinations.

Pilot navigated severe weather/snow storm with skill. Described his intentions clearly

Little warm on the plane and delayed for an hour

So excited very proud first of all I wanna thank kayak all updates very professional and fast alart And amazing cabin crew so nice to me they deserve big salute

The boarding process needs to be fixed. The zone don't work, especially when there is hardly anyone in zones 3, 4,and 5, leaving the majority of the passengers backed up in the aisle, especially because passengers seated near the front are blocking passengers who are seated in the rear of the plane. It would also help if the size of carry on bags was more strictly enforced.

Awful. They won’t help me with anything. I booked on American but they abdicated to Iberia. The ticket was overpriced. Everything negative

I enjoyed the extra leg room compared to other airlines. The first stewards made my daughter’s birthday special by giving her an extra snack. Then the last one coming home from Chicago to Appleton made our night really enjoyable Thanks for making our trip enjoyable

It was good..clean, comfy seat. Friendly warm welcoming crew. Was able to check my cabin luggage at the gate which I was able to pickup in a decent time from baggage claim. The app gave all updates from delays to baggage claim info. Overall smooth flight.

It was a typical flight. We had a delay which seems to be the normality now. And we had no in flight service due to conditions.

After we landed we sat on the tarmac for 1.5 hours waiting to get to our gate. Ridiculous.

Terrible. Flight delayed for more than 8 hours with only a $12 meal voucher provided for the inconvenience. The airplane did not have breaks on arrival yet they still made us go through the motions and board on time knowing we could not take off then sit for 40+ minutes before having to get of the time. A complete waste of my time. I cannot believe they can stay business with these shenanigans. I’ll avoid this company like the plague moving forward as the lack of accountability is disgraceful.

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.

Late taking off. ATC sent us circling around Chicago for almost an hour, after landing taxied for 40 minutes.

I waited for 4+ extra hours to even board when i was fighting off a cold. So i was sitting there in the airport with a fever and chills while spirit wasted my time. Then once on the plane we had at least an extra hour of taxiing before and after takeoff. Really poor airline, no amenities to speak of, and a lack of organization that will just ruin your experience.

Terrible. They cancelled the flight at the last minute after I had checked in at the airport and then told me they could only put me on a flight after 7 days. Pathetic.

Flight was on time. Friendly crew. Gate agents in the other hand were very unfriendly.

Bought round trip tickets. Ended up upgrading to first class. Both flights were new planes but hadn’t been equipped with WiFi and there were no charging ports at my seat despite it being new and first class accommodations.

Like: seats that don't move; fast boarding; engaging crew; low-prices; individual gate at LGA; access to restrooms at the gate Dislike: no water on the flight

To be Honest they canceled my flight and didn't have other options. Until 4 says later and I have a 2yr old very disappointed.

Very well recently! Frontier is improving and less harrassing customer on luggages! Positive!

Good for a budget airline! It was easy to get on, staff was really nice. Can’t say anything about the food or entertainment because it wasn’t available, which is fine.

I am writing to express my disappointment with my recent Frontier Airlines flight. I was charged $99 at the gate because my bag was said to be too large, yet once onboard there was no available overhead bin space, and I was required to place the bag under the seat in front of me anyway. This made the charge feel unnecessary and unfair. Additionally, before the flight even took off, I was asked to move from the seat I paid for into a middle seat so another passenger and her cat could have my seat to themselves. I was not offered compensation or an explanation for being moved from a paid seat. Between the unexpected bag fee and being forced to give up my seat, this experience fell well below acceptable customer service standards. I would appreciate a review of this situation and appropriate compensation.

It was costly and difficult to check in. $85 to take a small suitcase with me, carry on or checked and $75 on the return trip, Plus $25 if I didn't check my self in check in $25, because I couldn't do it on the kiosk. Small very uncomfortable seats, waited on the runway for near an hour each way. It was my worst flight to date.

It was ok. It was expensive to check 2 bags ($75.00 per bag), and then it took a long time to wait for shuttle to take us from one terminal to the terminal where the plane was taking off at LAX. And all of this for a flight where we had to pay for any food or drink that was not water.

It didn’t happen. I booked it and then was told it wasn’t available and then forced to pay far higher prices for a worse option

A 630departure flight Delayed 6hours! They changed my gate, I moved to the new gate. Had our flight on the screen for 12noon departure. I go get above to eat, check screen again and the flight was gone, no notice no announcement, nothing!! They sent my bag on the flight I wasn’t on, got it back to me 3days later. Thank goodness they did refund my money but I will NEVER fly them again.

Due to weather, my flight was delayed, further delayed, then canceled. I eventually got through to a support person who helped me find a different route out of MSP, but to get to DIA, they didn't want to, but eventually did help with the connection ticket purchase. But even this replacement flight was delayed time and time again, and I would have missed my connecting flights and I didn't want to get stuck in a layover city, so after 12 hours at the airport with two young boys who were very tired, we just cancelled our plans and spent the week at home, instead of Nana's.

Plane and crew on board were fine. Everything else was terrible.

The third party booking with cheapflightsfares was awful. Kayak should NOT partner with them. They sold me a bundle including seat selection and carry-on, but did not book the carry-ons with Frontier, so I’m out of pocket for $414 more while I await resolution.

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

Information on your arrival and departure airports