$133 Find Cheap Flights from San Francisco 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 Francisco to Illinois departing on 5/27. 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

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These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Francisco to Illinois.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Francisco to Illinois.
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Cheap Flights from San Francisco to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$289
Moline
Moline1 stop$349
Peoria
Peoria1 stop$324
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$400
Springfield
Springfield1 stop$565
St. Louis
St. Louis1 stop$329
Decatur
Decatur1 stop$414
Marion
Marion2 stops$799
Paducah
Paducah1 stop$391
Chicago
Chicago1 stop$289
Moline
Moline1 stop$349
Peoria
Peoria1 stop$324
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$400
Springfield
Springfield1 stop$565
St. Louis
St. Louis1 stop$329
Decatur
Decatur1 stop$414
Marion
Marion2 stops$799
Paducah
Paducah1 stop$391

Book Cheap San Francisco 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 Francisco 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 Francisco to Illinois

Fri, Jun 12 - Tue, Jun 16
Frontier Logo
10:58 pm - 5:07 am
SFO
-
ORD
28h 09m
1 stop
Frontier Logo
7:20 am - 2:16 pm
ORD
-
SFO
8h 56m
1 stop
$289Frontier
Sun, May 31 - Thu, Jun 11
Frontier Logo
11:59 pm - 2:12 pm
SFO
-
MDW
12h 13m
1 stop
Frontier Logo
4:10 pm - 11:02 pm
MDW
-
SFO
8h 52m
1 stop
$290Frontier
Tue, Jun 16 - Tue, Jun 23
United Airlines Logo
11:30 pm - 5:53 am
SFO
-
ORD
4h 23mnonstop
United Airlines Logo
9:48 pm - 12:45 am
ORD
-
SFO
4h 57mnonstop
$291United Airlines
Mon, Jun 1 - Tue, Jun 9
Southwest Logo
10:55 pm - 8:25 am
SFO
-
MDW
7h 30m
1 stop
Southwest Logo
5:05 am - 9:45 am
MDW
-
SFO
6h 40m
1 stop
$292Southwest
Mon, Jun 1 - Tue, Jun 9
Delta Logo
5:50 am - 4:29 pm
SFO
-
ORD
8h 39m
1 stop
Delta Logo
3:55 pm - 9:00 pm
ORD
-
SFO
7h 05m
1 stop
$292Delta
Thu, Jul 9 - Wed, Jul 15
United Airlines Logo
3:10 pm - 9:34 pm
SFO
-
ORD
4h 24mnonstop
United Airlines Logo
6:10 am - 8:47 am
ORD
-
SFO
4h 37mnonstop
$296United Airlines
Tue, Jul 14 - Wed, Jul 29
Southwest Logo
5:15 am - 11:25 am
SFO
-
MDW
4h 10mnonstop
Southwest Logo
9:30 pm - 12:10 am
MDW
-
SFO
4h 40mnonstop
$296Southwest
Mon, Jun 8 - Tue, Jun 16
American Airlines Logo
11:10 pm - 5:39 am
SFO
-
ORD
4h 29mnonstop
American Airlines Logo
9:00 pm - 11:58 pm
ORD
-
SFO
4h 58mnonstop
$297American Airlines
Sat, Sep 12 - Sat, Sep 19
American Airlines Logo
9:07 am - 5:40 pm
SFO
-
PIA
6h 33m
1 stop
American Airlines Logo
6:33 pm - 11:09 pm
PIA
-
SFO
6h 36m
1 stop
$331American Airlines
Mon, Jun 22 - Fri, Jul 3
Delta Logo
11:59 pm - 11:26 am
SFO
-
BMI
9h 27m
1 stop
Delta Logo
12:09 pm - 7:54 pm
BMI
-
SFO
9h 45m
1 stop
$349Delta
Booking Insights

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

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

How much is a round-trip flight from San Francisco to Illinois?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from San Francisco to Illinois departing in June.

What is the cheapest San Francisco 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 Francisco found in the last 72 hours was to Chicago, at $279 round-trip. The most popular route is from San Francisco (SFO) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $299.

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

The average price for all round-trip flights from San Francisco 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 at night, when round-trip flights cost $433 on average. Morning departures are around 1% more expensive 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 $471.

Can I save money by flying with a layover from San Francisco 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 $444, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from San Francisco 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 Francisco to Illinois is September, when tickets cost $288 (return) on average. On the other hand, the most expensive months are January and February, when the average cost of round-trip tickets is $1,068 and $814 respectively.

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

The average price of all round-trip flights from San Francisco 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 Tuesday, 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 Francisco to Illinois. For your return ticket, we recommend flying on a Thursday and avoiding Sundays for the best deals.

How far in advance should I book a flight from San Francisco 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 Francisco 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 Francisco to Illinois, you should book around 4 weeks before departure, which saves you about 44% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 7 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$133
Best time to beat the crowds with an average 5% drop in price.
Most popular time to fly with an average 3% increase in price.
Flight from San Francisco to Chicago Midway Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from San Francisco 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 Francisco to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from San Francisco 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 Francisco 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 Francisco 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 Francisco 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 Francisco 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 Francisco to the following destinations at these prices or less: Chicago $230 one-way - $409 round-trip

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

 
See real verified KAYAK customer reviews for airlines flying from San Francisco 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 Francisco 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 4294 reviews
8.6Crew
7.0Food
8.0Comfort
8.1Boarding
7.5Entertainment
Airline reviews

The checking experience in Orlando was terrible, almost missed the flight. Too many travelers and Southwest completely understaffed.

2.0 MediocreAnonymous, May 2026
MCO - MDW
Read more Southwest reviews

The checking experience in Orlando was terrible, almost missed the flight. Too many travelers and Southwest completely understaffed.

The entire experience from boarding to landing was amazing! The crew were very friendly. Will definitely be back.

no service at all due to turbulence. they should've at least given us snacks, there were only 10 people on the entire flight.

Delayed flight, lack of information, boarding process is a mess as is the carryon luggage causing issues when leaving the plane….just a poor experience.

Comfortable. Easy. No problems. Just wish they had gf options for snacks.

The crew was very kind and made going to Hawaii relaxing and fun to look forward to! Thank you Southwest for a pleasant flight!

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

Great flight. I didn't get a drink because I was asleep whole on the flight.

Terrible. Even though there’s assigned seating now, they are still the slowest boarding airline of anyone.

It was good from LAX to Phoenix, But the connection in Phoenix to Tulsa was not that great. The staff on both flights were great. The choice of free entertainment was ok nothing to brag about. The 45 min delay because of some electrical issue wasn't great from Phoenix to Tulsa. We sat there with hardly any air, The seat I had was between windows so the side of the plane pushed in on you. My being a bigger man it then made the seating area uncomfortable. The seats on the plane had no power to connect to recharge your phone or anything. I would recommend that they should look into a slot or clamp to hold your phone to enjoy while watching the entertainment choices hands-free. Also make it possible to raise the inner seat by the window be able to raise the arm rest up to make more room for larger people to set more comfortably. I would also say other then that stop price gouging the airfare or nickel and diming everything. Not fair for people having to fly for emergencies and be paying for higher prices due to the season or holidays. Your making your money either way and the cost of flying is still going to be the same regardless if there's 100 people or 200 people.

The flight would have been very good , if not dor the constantly screaming baby in the row behind me. Is there a way to isolate people traveling with infants? This is not the first time this has happened to me.

They treat me well because of my one world status. Crew is attentive and professional. One of the best airlines out there.

Crew were bad Didn’t help with luggage When asked for a glass of wine, I was told that they will serve later , which they didn’t to Me and didn’t serve anyone else in First class . Didn’t offer any snacks , Chips or Nuts to anyone . Flight was not crowded either. Worst Service/ or No Service !

Alaska drastically changed our flight from a direct flight to a flight with connection and a long layover. So we canceled the Alaska flight and we learned a valuable lesson that we will never book through kayak again because the third party travel agent tried to withhold our money.

Four hour delay. Missed our event. And they offered me $75. Absolutely shameful.

I have been flying commercial for decades. I was in one of the ladder boarding groups, had my bag tagged because they thought there was not going to be enough space for it in the overhead bins. I politely asked one of the attendance if I could try to find a space- she said I could and I did. I then took the bag tag off and gave it to one of the other attendants as I was told to do by the first one. He, in a curt, anal, and disrespectful manner, told me that I needed to take my bag down from the overhead bin and check it. This was a situation I’ve never encountered before. The attendant’s attitude was confrontational and belittling in front of other onlooking passengers as if daring me to challenge him. I am a physician who takes care of patients day in and day out. Not wanting to make a scene, I calmly told him, “do what you need to do.” he took my bag down from the overhead bin, put the back tag back on it, and checked it only to make room for another bag that was also supposed to be technically checked by a following passenger. The same male attendant later came up to me and said “you shouldn’t have showed me the bag tag,” as if conveying that he was just following protocol was a justification for treating me like a kid out of line. I cared about this because it took 15 minutes from my life to then retrieve the bag at baggage claim and it also felt like really poor customer service. I understand the need for protocols. This is also a service industry, and we the passengers are the clients. We should be made to feel welcome and respected and our life in transit made as easy as it can be within reason. This attendant clearly needs to be reminded of that. Of note, an older female fellow passenger sitting next to me agreed with this assessment.

Nice crew, healthy snacks and drinks available. Flight to Seattle was short and comfortable.

had to be rerouted due to a medical emergency onboard. Alaska crew treated the patient with utmost respect and continued to keep the passengers updated the entire way through, which I appreciate. But it took 4 hours from landing until we were able to be airborne again, causing us to not get into SFO until ~2 am. I understand it was a tough situation for everyone, but that was an indecent wait.

I love Alaska! We arrived on the later side without seat assignments only to find the had oversold the flight by 1. The attendants worked extra hard to find a way for our party of 7 to stay together and we made it on the flight! Loved the free WiFi also!

Delay for switching planes. Then delay after delay (mechanical) after boarding so that we were almost 3 hrs late, getting in at 230am. Crew was good.

No screens or meal options. Freezing cold. Dirty seats. Left late.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

It was a red-eye, but the flight felt surprisingly quick. The seats were very comfortable, and that made resting much easier. I also want to thank the gentleman seated next to me, who graciously moved so my mom could sit beside me. We slept almost the entire way. The cabin crew was respectful in not disturbing us, while also being courteous and professional throughout. Thank you, United.

Boarding was again a "free for all". We were boarding group 4, and almost the entire plane was able to board before us. It's a shame that someone who follows the rules, gets the short end of the stick. Not fair.

It was perfect! I've never flown with United before, but I definitely will in the future

They delayed the flight from 9:00 to 11:55 At 11:45 they canceled the flight. I paid a premium price for the tickets with poor service

Seats are uncomfortable. This has been a trend in the industry for decades. Trying to fit more seats on each plane to increase profits at the expense of the passenger.

Staff were good. My seat was in need of repair, but for a short flight was not problematic. Usual basic snack and drink setup that you'll find on any US carrier. Over, a decent, basic flight.

Flight delayed for more than 16 hrs and no effort was spent to provide an alternate

it was a very short flight so my expectations were low.

Premium Economy Good crew, good service, excellent food. Seat back screen just not bright enough.

It was good, the staff was great, and the food, was as usual, tea and biscuit. Bathroom was clean, and the plane was clean as well.

The SFO Lounge crew were amazing. The bartender Faris was great. Thanks!

Very good I can’t complain one bit. Thank you American Airlines for making my flight enjoyable and safe!

The staff and service on American Airlines were truly outstanding. I had requested wheelchair assistance for my mother due to her knee issues, and the team went above and beyond every step of the way—from boarding in Boston to our arrival in Chicago. Their care, professionalism, and attentiveness made the entire experience smooth and stress-free. I’m very grateful for the support they provided.

The new planes (American Eagle) are beautiful and especially comfortable. The flight attendants are consistently professional and courteous. And, while it may seem inconsequential, the new liquid tube of coffee creamer—in contrast to the powdered coffee creamer—makes all the difference in a cup of coffee.

Boarding was quick and efficient. We arrived at our destination early.

I'm not sure American is capable of on-time arrivals and departures. When you land at ORD, you almost always get held on the tarmac because your gate is still occupied. I may have missed my connection, but that ended up up being significantly delayed as well. Once again, I finally got home well after midnight.

Crew at the gate was very crabby and not at all polite. The plane was very hot the entire flight. And the seat cushion was very worn out.

The staff are very, very professional. It's what flying should feel like.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

They didn’t offer a water, even after I asked

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

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

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.

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.

This company socks. It's fraud. They canceled our flight yesterday, and today we were late because of a really long line at the check in bag. At the rebook station, there was ton of people. The workers were all rude. I am gonna make a report to FTC.

When I wanted to check in 3 hours prior to boarding time, the employees mentioned “a little over an hour delay” so I waited for an hour then I went to go look for food in the terminal and most people from that flight were in the same area looking for food. Finally I decided after food to check to see if it’s anytime closer and now it’s 2 mins until boarding closes?! What are you kidding me? I didn’t receive anything via sms about boarding now nor via email or on the intercom. I luckily made it through, barely, and then there’s no room for my carry on mind you I’m in the very first row so I had to place my purse in one further row back and my carry on sections down. Not sure who pays for better seats to get your stuff placed all over the plane but that was the worst experience I’ve ever had flying with anyone.

The single worst check in experience I could imagine. I’ll never do any business with Frontier or any affiliated company

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

Information on your arrival and departure airports