$94 Find Cheap Flights from San Francisco to Illinois - Compare and Save

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 9/1. 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.
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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
Chicagononstop$314
Moline
Moline1 stop$332
Peoria
Peoria1 stop$331
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$400
Springfield
Springfield1 stop$565
St. Louis
St. Louis1 stop$396
Decatur
Decatur1 stop$344
Quincy
Quincy2 stops$584
Paducah
Paducah2 stops$683
Chicago
Chicagononstop$314
Moline
Moline1 stop$332
Peoria
Peoria1 stop$331
Bloomington
Bloomington1 stop$349
Champaign
Champaign1 stop$400
Springfield
Springfield1 stop$565
St. Louis
St. Louis1 stop$396
Decatur
Decatur1 stop$344
Quincy
Quincy2 stops$584
Paducah
Paducah2 stops$683

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

Tue, Jul 28 - Wed, Jul 29
Southwest Logo
11:40 pm - 5:55 am
SFO
-
MDW
4h 15mnonstop
Southwest Logo
6:40 pm - 11:20 pm
MDW
-
SFO
6h 40m
1 stop
$314Southwest
Tue, Jul 21 - Fri, Jul 24
Frontier Logo
9:00 pm - 5:37 am
SFO
-
ORD
6h 37m
1 stop
Frontier Logo
9:13 pm - 8:45 pm
ORD
-
SFO
25h 32m
1 stop
$314Frontier
Sat, Jul 25 - Sat, Aug 1
United Airlines Logo
3:10 pm - 9:38 pm
SFO
-
ORD
4h 28mnonstop
United Airlines Logo
6:10 am - 8:47 am
ORD
-
SFO
4h 37mnonstop
$315United Airlines
Tue, Jul 14 - Wed, Jul 22
Multiple Airlines Logo
8:23 pm - 6:17 am
SFO
-
ORD
7h 54m
1 stop
Multiple Airlines Logo
6:20 am - 11:49 am
ORD
-
SFO
7h 29m
1 stop
$317Multiple Airlines
Wed, Jul 29 - Wed, Aug 5
Multiple Airlines Logo
9:00 pm - 12:24 pm
SFO
-
RFD
13h 24m
1 stop
Multiple Airlines Logo
8:58 pm - 4:06 pm
RFD
-
SFO
21h 08m
1 stop
$319Multiple Airlines
Fri, Jul 24 - Sat, Jul 25
United Airlines Logo
6:34 pm - 12:59 am
SFO
-
ORD
4h 25mnonstop
United Airlines Logo
7:30 am - 10:19 am
ORD
-
SFO
4h 49mnonstop
$320United Airlines
Fri, Aug 14 - Thu, Aug 20
American Airlines Logo
1:45 pm - 12:29 am
SFO
-
ORD
8h 44m
1 stop
American Airlines Logo
3:20 pm - 6:00 pm
ORD
-
SFO
4h 40mnonstop
$321American Airlines
Mon, Aug 10 - Tue, Aug 18
Delta Logo
12:12 am - 8:39 am
SFO
-
MDW
6h 27m
1 stop
Delta Logo
9:24 am - 10:15 pm
MDW
-
SFO
14h 51m
2 stops
$325Delta
Wed, Aug 19 - Wed, Aug 26
American Airlines Logo
6:36 am - 3:53 pm
SFO
-
PIA
7h 17m
1 stop
American Airlines Logo
12:20 pm - 5:49 pm
PIA
-
SFO
7h 29m
1 stop
$331American Airlines
Wed, Aug 5 - Fri, Aug 21
Delta Logo
1:45 pm - 11:16 pm
SFO
-
BMI
7h 31m
1 stop
Delta Logo
12:09 pm - 7:39 pm
BMI
-
SFO
9h 30m
1 stop
$384Delta
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 July.

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 5 days was to Chicago, at $299 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 5 days 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 $457 on average. Morning departures are around 3% 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 $498.

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 $471, 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 $296 (return) on average. On the other hand, the most expensive months are January and February, when the average cost of round-trip tickets is $1,050 and $812 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 Wednesday, as we generally find the cheapest rates on that day for this route. On the other hand, Monday 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 42% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$94
Best time to beat the crowds with an average 1% drop in price.
Most popular time to fly with an average 1% increase in price.
Flight from San Francisco to St. Louis

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 $250 one-way - $418 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.
7.9
SouthwestOverall score based on 4250 reviews
8.1Boarding
7.5Entertainment
7.0Food
8.0Comfort
8.6Crew
Airline reviews

I think Southwest is the number one airline that anyone can fly I have flown for the first time Frontier and what a joke and their customer service United was a very strange experience I'm only sticking to Southwest from here on out for sure

10.0 Excellentkelly, Jul 2026
SFO - PHX
Read more Southwest reviews

I think Southwest is the number one airline that anyone can fly I have flown for the first time Frontier and what a joke and their customer service United was a very strange experience I'm only sticking to Southwest from here on out for sure

3 hour delay. Had to change plans and was still delayed.

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

The weather could have been better. There was a 40 minute ATC delay in SFO because of marine fog and a micro cell storm delayed landing and take-off at Nashville. The gate was changed 5 minutes from boarding from gate B3 to gate C23 at Nashville airport.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

Employees were kind and funny, as always! Flight was late but no announcements were made for people with tight connections to help them transition quickly. No service due to turbulence.

I used to fly SWA all the time. I know the crew has their little acts that are often fun, and entertaining. On this flight one of the crew was just not nice. Very surprising.

The flight was delayed for almost an hour. We sat on the tarmac. There was no announcement. Not by the pilot or the crew. And for some reason, there was no beverage service, so even though it was a short flight, we had sat on the tarmac and the extra hour delay made me understandably thirsty. Water would’ve been nice if they had offered it. And for the first time, I forgot to bring my own water bottle. Reminder to bring your own water bottle because you never know if you’re going to get a beverage.

It was a new plane with larger overhead bins & charging ports at the seats.

Luggage was intact and arrived at the destination. What more could you ask for.. haha. The delay in arrival wasn’t SW fault.. just selfish passengers not wanting to check their luggage knowing they were in the last boarding groups

Flight delayed four separate times. I’m now one hour hours late to landing.

The plane was an older model, so it wasn’t as comfortable as others. The flight attendants were not helpful during onboarding. It was a full flight so there was chaos finding space for baggage.

Awesome! On time flight, early arrival, and a complimentary upgrade!

Delta’s staff is unmatched. From the gate agents, to the pilots, to the flight attendants… all top of the industry.

Our flight from SFO to MSP was right on time on 11/15/2025. No delays. As we approached MSP at about 8 pm, we circled in the air until 8:40 pm so I don't call that efficient for MSP. I think the captain should announce the delay and why. (as if we all don't know that we are just circling around the area, slowing down, speeding up, slowing down.) Thank you. Marilyn Fischer

Excellent flight, the planes were newer, they did a nice job with boarding, great service overall.

Thank you for not flipping the plane on the run way. You guys get a 5 star rating for the flight!!!

Boarding is, as it always is… horrible. Gate lice. Slow moving zones. Too many people with carry ons

New boarding doesn't make sense. Filling front first is slow.

There was plenty of overhead room but half of the passengers were told they had to check their carryon bags. My partner and I checked in as early as possible and our seats were split across the aisle.

Lost one piece of luggage even though I checked in 2.5 hours before the flight

Horrifying Almost 2 million miles. Bring your own food and drink. One coffee or drink every three hours. Have to order meals on app more than 24 hours ahead Tiny and dirty bathrooms

My service dog and I were asked to deplane just before they closed the door - clearly very last minute they couldn’t find the documentation that I have filled out many many times before that is for flying service animals. I purposely purchase 3seats (a whole row) since he is large and not all passengers want to sit next to a dog on a cross country flight. The plane departed with my husband on it!!! They made me fill out a hard copy of the same form and had to reschedule me on a later flight where they could find 3 seats together!! I’ve done this so many times before - clearly the error was on their part in a technology glitch - but really people - do better!! Very traumatic - and my husband had to wait for us when he landed ….so bad. Poor pup was confused and tired.

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

While the staff was pleasant and helpful, the following observations are for your awareness. There was some delay on the tarmac on take off and landing. The paid lunch/food offerings were limited. Entertainment was only available on WiFi at a cost.

United WiFi is consistently unusable (it can take 10 mins to load a single web page). If you need Wifi to do work, be prepared to lose half a day of productivity.

Flight was delayed multiple times without giving any particular reason and the only thing that was communicated was that 'Aircraft is getting ready'. I was stuck at SFO airport for 15 hours and finally took Southwest Airlines flight back home to Dallas.

I was not clear if food was offered or not.

Agency very bad had to cancelled my booking too many changes in the flight changed my flight to 1 week

Take-off delayed an hour because of a missing flight officer, so,arrived in Charlotte lates causing many passengers to miss connections. Otherwise a very good flight, safe and comfortable, with an excellent professional crew.

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

Not good. One of my luggage is missing. And until now they can’t find it

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

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.

It was nice being on a flight that had working wifi. The boarding was quick - why don’t all airlines have small boarding groups window to aisle? Makes so much sense!!! I was disappointed to be the first person stopped to have to gate check my carryon. Especially when there was plenty of overhead space at the back! But I get it…keeps it moving. Crew was nice.

Internet service was erratic. Crew service was poor and slow. My luggage on this non-stop flight was lost and not recovered

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

Frontier had yet another flight cancellation. Have never made a complete round trip with this airline without at least one leg getting cancelled. Miserable flights - dirty, uncomfortable planes that apparently always have issues since I've had multiple delays and cancellations with them.

No frills for sure. No gate announcements about flight delay, not even water to drink on the flight.

I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.

It was a redeye flight, so every passenger just wanted to sleep, but through the entire flight, the flight crew made announcements over the loudspeaker at maximum volume every few minutes making sleep impossible. For example: it’s 2am, and the crew decides to give an extremely detailed announcement about snacks and beverages for sale. And 3am is the perfect time to wake up everyone with a lengthy announcement about how to get a coffee refill and how to take advantage of new offer from frontier for a credit card.

While booking it was not obvious that I had to pay for carryon. Realized it only during check-in. Overall, meh!

Stop changing gates at sfo. When you are elderly going back for it’s not fun.

After 5 hours of delay, they cancelled the flight. Very disappointed

My flight to LA was cancelled. I waited at the airport for 3 hrs saying it was delayed and then all of a sudden it was cancelled. Frontier only gave me a voucher and refund but could not rebook me. Flights on other airlines were too expensive last minute. I had to drive down to LA and didn’t even take my return flight home since I had to drive. One of the worst airline experiences in my life. It’s crazy how airlines can just upend people’s plans just like that.

The flight attendence were extremely rude and I am disabled

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

Information on your arrival and departure airports