What airlines fly to Illinois?

American Airlines, United Airlines and Frontier are the top three most popular airlines that fly to Illinois from San Diego according to our data. American Airlines is the first choice among our users, with 53% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 8 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

How many flights depart from San Diego to Illinois on average per day?

As of October 2025, 18 flights take off from San Diego and land in Illinois each day. The most common flight departure time for this route is 6:00AM, with 58% of daily flights taking off at noon.

What is the cheapest airline that flies from San Diego to Illinois?

Frontier, United Airlines, and Southwest are the most popular carriers operating from San Diego to Illinois

How many flights depart from San Diego to Illinois on average per week?

128 flights are operational weekly from San Diego to Illinois as of October 2025. The most popular departure day for this route is Thu, with 34% of flights per week taking off on this day.

When did momondo last update prices for flights from San Diego Airport to Illinois?

Prices for flights from San Diego Airport to Illinois refresh daily.

How many operators does momondo search for flights from San Diego Airport to Illinois?

As of October 2025, there are 8 operators available to choose from for flights from San Diego Airport to Illinois.

How old do you have to be to fly from San Diego Airport to Illinois?

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from San Diego Airport to Illinois.

What documentation or ID do you need to fly to Illinois?

The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$61 Cheap Flights from San Diego to Illinois in 2025/26

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Cheap round-trip flights

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6:34 am - 10:14 amSAN-STL

25h 40m1 stop

7:43 pm - 7:15 pmSTL-SAN

25h 32m1 stop

$124Frontier

Find Deal

Tue, Dec 16 - Wed, Dec 17

6:34 am - 10:14 amSAN-STL

25h 40m1 stop

7:43 pm - 11:59 pmSTL-SAN

6h 16m1 stop

$130Frontier

Find Deal

Thu, Dec 11 - Mon, Dec 15

5:00 pm - 11:10 pmSAN-ORD

4h 10mnonstop

9:00 am - 11:25 amORD-SAN

4h 25mnonstop

$157Alaska Airlines

Find Deal

Tue, Mar 3 - Tue, Mar 10

1:25 pm - 7:46 pmSAN-ORD

4h 21mnonstop

6:10 pm - 8:45 pmORD-SAN

4h 35mnonstop

$165American Airlines

Find Deal

Wed, Dec 3 - Sun, Dec 7

10:30 pm - 4:38 amSAN-ORD

4h 08mnonstop

7:10 am - 9:40 amORD-SAN

4h 30mnonstop

$167United Airlines

Find Deal

Mon, Dec 22 - Sat, Jan 24

5:00 pm - 10:55 pmSAN-MDW

3h 55mnonstop

5:15 am - 9:25 amMDW-SAN

6h 10m1 stop

$167Southwest

Find Deal

Wed, Nov 19 - Wed, Nov 26

1:05 pm - 7:26 pmSAN-ORD

4h 21mnonstop

6:10 pm - 8:45 pmORD-SAN

4h 35mnonstop

$170American Airlines

Find Deal

Thu, Nov 27 - Thu, Dec 4

5:31 pm - 11:32 pmSAN-ORD

4h 01mnonstop

8:49 pm - 11:13 pmORD-SAN

4h 24mnonstop

$171Alaska Airlines

Find Deal

Mon, Nov 24 - Tue, Nov 25

9:10 am - 9:50 pmSAN-ORD

10h 40m1 stop

4:25 pm - 9:10 pmORD-SAN

6h 45m1 stop

$172Southwest

Find Deal

Sat, Dec 6 - Tue, Dec 9

5:21 pm - 11:30 pmSAN-ORD

4h 09mnonstop

7:10 am - 9:39 amORD-SAN

4h 29mnonstop

$173United Airlines

Find Deal

Sat, Nov 22 - Tue, Nov 25

Alaska Airlines flights from San Diego to Illinois

Our best Alaska Airlines deals on San Diego to Illinois flight tickets

Alaska Airlines

Mar 3

SAN5:00 pmSan Diego

4h 10m

ORD11:10 pmChicago O'Hare Intl

Mar 10

ORD9:00 amChicago O'Hare Intl

4h 25m

SAN11:25 amSan Diego

$157

Find similar

Alaska Airlines

Nov 24

SAN5:31 pmSan Diego

4h 01m

ORD11:32 pmChicago O'Hare Intl

Nov 25

ORD8:49 pmChicago O'Hare Intl

4h 24m

SAN11:13 pmSan Diego

$171

Find similar

Alaska Airlines

Mar 2

SAN8:05 amSan Diego

3h 54m

ORD1:59 pmChicago O'Hare Intl

Mar 9

ORD2:59 pmChicago O'Hare Intl

4h 25m

SAN5:24 pmSan Diego

$175

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United Airlines flights from San Diego to Illinois

Our best United Airlines deals on San Diego to Illinois flight tickets

United Airlines

Dec 22

SAN10:30 pmSan Diego

4h 08m

ORD4:38 amChicago O'Hare Intl

Jan 24

ORD7:10 amChicago O'Hare Intl

4h 30m

SAN9:40 amSan Diego

$167

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United Airlines

Nov 22

SAN5:21 pmSan Diego

4h 09m

ORD11:30 pmChicago O'Hare Intl

Nov 25

ORD7:10 amChicago O'Hare Intl

4h 29m

SAN9:39 amSan Diego

$173

Find similar

United Airlines

Nov 26

SAN5:15 pmSan Diego

4h 09m

ORD11:24 pmChicago O'Hare Intl

Dec 2

ORD7:55 pmChicago O'Hare Intl

4h 35m

SAN10:30 pmSan Diego

$181

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Fly from

Fly to

Route

Depart

Return

Price

San DiegoSt. Louis

SAN - STL

SANSTL

San Diego

Tue 12/16

6:34 am-10:14 am

1 stop25h 40m

Lambert-St Louis

Wed 12/17

7:43 pm-7:15 pm

1 stop25h 32m

$124

San DiegoSt. Louis

SAN - STL

SANSTL

San Diego

Thu 12/11

6:34 am-10:14 am

1 stop25h 40m

Lambert-St Louis

Mon 12/15

7:43 pm-11:59 pm

1 stop6h 16m

$130

San DiegoChicago

SAN - ORD

SANORD

San Diego

Tue 3/3

5:00 pm-11:10 pm

Nonstop4h 10m

Chicago O'Hare Intl

Tue 3/10

9:00 am-11:25 am

Nonstop4h 25m

$157

San DiegoChicago

SAN - ORD

SANORD

San Diego

Wed 12/3

1:25 pm-7:46 pm

Nonstop4h 21m

Chicago O'Hare Intl

Sun 12/7

6:10 pm-8:45 pm

Nonstop4h 35m

$165

San DiegoChicago

SAN - ORD

SANORD

San Diego

Mon 12/22

10:30 pm-4:38 am

Nonstop4h 08m

Chicago O'Hare Intl

Sat 1/24

7:10 am-9:40 am

Nonstop4h 30m

$167

San DiegoChicago

SAN - MDW

SANMDW

San Diego

Wed 11/19

5:00 pm-10:55 pm

Nonstop3h 55m

Chicago Midway

Wed 11/26

5:15 am-9:25 am

1 stop6h 10m

$167

San DiegoChicago

SAN - ORD

SANORD

San Diego

Thu 11/27

1:05 pm-7:26 pm

Nonstop4h 21m

Chicago O'Hare Intl

Thu 12/4

6:10 pm-8:45 pm

Nonstop4h 35m

$170

San DiegoChicago

SAN - ORD

SANORD

San Diego

Mon 11/24

5:31 pm-11:32 pm

Nonstop4h 01m

Chicago O'Hare Intl

Tue 11/25

8:49 pm-11:13 pm

Nonstop4h 24m

$171

San DiegoChicago

SAN - ORD

SANORD

San Diego

Sat 12/6

9:10 am-9:50 pm

1 stop10h 40m

Chicago O'Hare Intl

Tue 12/9

4:25 pm-9:10 pm

1 stop6h 45m

$172

San DiegoChicago

SAN - ORD

SANORD

San Diego

Sat 11/22

5:21 pm-11:30 pm

Nonstop4h 09m

Chicago O'Hare Intl

Tue 11/25

7:10 am-9:39 am

Nonstop4h 29m

$173

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How to get the cheapest flight ticket from San Diego to Illinois

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Illinois?

The cheapest month to fly to Illinois from San Diego is in September. Flight prices, which tend to average around $240, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of September, then flying in August is also cheap. Prices for this month can be found on momondo for an average of $251.

What is the cheapest day to depart on your flight to Illinois?

The cheapest day to depart from San Diego to Illinois is on a Wednesday when prices can be found for as low as $410. Flights from San Diego to Illinois on a Sunday will generally be more expensive and average around $585. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Illinois?

Our most recent data shows that the best time of day to fly to Illinois is in the afternoon. Flights from San Diego to Illinois during this time can be as low as $269. Flights in the morning are often more expensive with an average ticket price of $484.

What is the cheapest San Diego to Illinois flight route?

Fly from San Diego to Chicago O'Hare Intl for the best San Diego - Illinois flight prices

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

You are more likely to see cheaper flights to Illinois from San Diego when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $356 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from San Diego for as low as $258 on momondo.

What cabin class options are available on San Diego to Illinois flights?

There are 4 cabin classes available to choose from on San Diego to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on San Diego to Illinois flights?

You could potentially save up to 10% on your flight if you consider stops on a San Diego to Illinois flight.

Cheap San Diego to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from San Diego to Illinois

Best Price Found	$139
Fastest flight time	3h 30m
Direct flights	Every day
Airports in Illinois	1 airport

The best one-way flight to Illinois from San Diego in the past 72 hours is $139. The best round-trip flight deal from San Diego to Illinois found on momondo in the last 72 hours is $268.

The fastest flight from San Diego to Illinois takes 3h 30m

Direct flights go from San Diego to Illinois every day.

There is 1 airport near Illinois: Lambert-St Louis (STL)

Search flight deals

When did momondo last update prices for flights from San Diego Airport to Illinois?
Prices for flights from San Diego Airport to Illinois refresh daily.
How many operators does momondo search for flights from San Diego Airport to Illinois?
As of October 2025, there are 8 operators available to choose from for flights from San Diego Airport to Illinois.
How old do you have to be to fly from San Diego Airport to Illinois?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from San Diego Airport to Illinois.
What documentation or ID do you need to fly to Illinois?
The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from San Diego to Illinois?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from San Diego to Illinois is Boeing 737-800 (29.43% of total bookings). The next most popular plane models are Airbus A321neo (15.87%), Boeing 737 MAX 9 (10.64%), and Boeing 737-800 Passenger/BBJ2 (winglets) (10.40%).

Best airlines flying from San Diego to Illinois

Compare and see reviews for airlines that fly from San Diego to Illinois with momondo

Airline	Rating	Free Cancellation	Price
Spirit Airlines	PriceFrom $110	Free Cancellation	Rating 6.3 8,115 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $118	Free Cancellation	Rating 5.8 3,123 reviews	Search Frontier flights
Hawaiian Airlines	PriceFrom $139	Free Cancellation	Rating 7.8 2,797 reviews	Search Hawaiian Airlines flights
Alaska Airlines	PriceFrom $149	Free Cancellation	Rating 8.0 11,214 reviews	Search Alaska Airlines flights
American Airlines	PriceFrom $168	Free Cancellation	Rating 7.2 11,030 reviews	Search American Airlines flights
United Airlines	PriceFrom $203	Free Cancellation	Rating 7.4 8,998 reviews	Search United Airlines flights
Southwest	PriceFrom $215	Free Cancellation	Rating 8.0 4,242 reviews	Search Southwest flights
Delta	PriceFrom $256	Free Cancellation	Rating 7.9 7,993 reviews	Search Delta flights

Why use momondo?

Why should I use momondo to find a flight deal from San Diego to Illinois?

It is quick and easy to find San Diego to Illinois flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Illinois that suits you.

Can I find flights from San Diego to Illinois with flexible booking policies on momondo?

Flights from San Diego to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from San Diego to Illinois?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Illinois from San Diego.

I’m not ready to book a flight from San Diego to Illinois right now. Can momondo alert me if prices change?

If you are not ready to book a flight from San Diego to Illinois now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Illinois and let you know when they change.

An easier way to manage your Illinois trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

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Find better results for your trip to Illinois

Popular cities in Illinois

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Cheap flights from San Diego to Illinois from $61

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from San Diego to Illinois departing on 12/25. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Filter for what you want

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Alaska Airlines flights from San Diego to Illinois

Our best Alaska Airlines deals on San Diego to Illinois flight tickets

United Airlines flights from San Diego to Illinois

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How to get the cheapest flight ticket from San Diego to Illinois

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Illinois?

What is the cheapest day to depart on your flight to Illinois?

What is the cheapest time of day to depart on your flight to Illinois?

Our most recent data shows that the best time of day to fly to Illinois is in the afternoon. Flights from San Diego to Illinois during this time can be as low as $269. Flights in the morning are often more expensive with an average ticket price of $484.

What is the cheapest San Diego to Illinois flight route?

Fly from San Diego to Chicago O'Hare Intl for the best San Diego - Illinois flight prices

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

What cabin class options are available on San Diego to Illinois flights?

There are 4 cabin classes available to choose from on San Diego to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on San Diego to Illinois flights?

You could potentially save up to 10% on your flight if you consider stops on a San Diego to Illinois flight.

What is the cheapest airline that flies from San Diego to Illinois?

Frontier, United Airlines, and Southwest are the most popular carriers operating from San Diego to Illinois

What airlines fly to Illinois?

How many flights depart from San Diego to Illinois on average per day?

As of October 2025, 18 flights take off from San Diego and land in Illinois each day. The most common flight departure time for this route is 6:00AM, with 58% of daily flights taking off at noon.

How many flights depart from San Diego to Illinois on average per week?

128 flights are operational weekly from San Diego to Illinois as of October 2025. The most popular departure day for this route is Thu, with 34% of flights per week taking off on this day.

Cheap San Diego to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from San Diego to Illinois

Best Price Found

Fastest flight time

Direct flights

Airports in Illinois

When did momondo last update prices for flights from San Diego Airport to Illinois?

How many operators does momondo search for flights from San Diego Airport to Illinois?

How old do you have to be to fly from San Diego Airport to Illinois?

What documentation or ID do you need to fly to Illinois?

What is the most popular plane model from San Diego to Illinois?

Best airlines flying from San Diego to Illinois

Compare and see reviews for airlines that fly from San Diego to Illinois with momondo

Why use momondo?

Why should I use momondo to find a flight deal from San Diego to Illinois?

Can I find flights from San Diego to Illinois with flexible booking policies on momondo?

How can momondo help me find flights from San Diego to Illinois?

I’m not ready to book a flight from San Diego to Illinois right now. Can momondo alert me if prices change?

An easier way to manage your Illinois trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Illinois

Popular cities in Illinois

Popular flights according to clicks in the last 7 days on momondo