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$52+ Cheap flights from San Diego (SAN) to Illinois

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/6. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ORD
feb. 7 — feb. 141
sáb. 2/7
sáb. 2/14
1 adult, Economy
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Cheap flight deals from San Diego to Illinois

Keep the following information in mind while searching for San Diego to Illinois flight deals. Data was last updated enero 8, 2026.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$109
(Kiwi.com)

One-way from

$52
(Trip.com)

Popular in

April

Cheapest in

October

Average price

$277

Good round-trip deal

$309 or less

Good one-way deal

$169 or less
Provider with most accurate pricing for San Diego-Chicago (CHI) flight deals.
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Provider most trusted by Cheapflights users for San Diego-Chicago (CHI) flights.
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From San Diego to Illinois
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One-way flight from San Diego to Illinois
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Highest demand for flights based on searches. 20% potential increase in price ($76 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in January 2026
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Price to beat on a round-trip flight from San Diego to Illinois.
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Price to beat on a one-way flight from San Diego to Illinois.
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Find flight deals from San Diego to Illinois

Cheapest flights from San Diego to Illinois
Explore the most affordable flight options available from San Diego to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on enero 8, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 2/278:35 amSAN - STL
1 stop27h 21mFrontier
lun. 3/21:54 pmSTL - SAN
1 stop12h 14mFrontier
Deal found 1/7$128
This Kiwi.com deal was found by Cheapflights users on 1/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 1/308:16 pmSAN - STL
1 stop16h 30mFrontier
lun. 2/21:40 pmSTL - SAN
1 stop12h 28mFrontier
Deal found 1/5$132
This Kiwi.com deal was found by Cheapflights users on 1/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 2/266:25 amSAN - STL
1 stop28h 44mFrontier
dom. 3/110:11 pmSTL - SAN
1 stop16h 54mFrontier
Deal found 1/7$139
This CheapOair deal was found by Cheapflights users on 1/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 1/287:00 amSAN - STL
1 stop5h 46mFrontier
jue. 1/2910:01 pmSTL - SAN
1 stop13h 25mFrontier
Deal found 1/7$145
This Kiwi.com deal was found by Cheapflights users on 1/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 3/19:09 amSAN - STL
1 stop26h 00mFrontier
mié. 3/45:18 pmSTL - SAN
2 stops26h 33mFrontier
Deal found 1/5$147
This WAYA deal was found by Cheapflights users on 1/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WAYA is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 1/178:00 amSAN - ORD
Nonstop4h 29mMultiple Airlines
lun. 1/268:00 amORD - SAN
1 stop7h 57mMultiple Airlines
Deal found 1/6$154
This Trip.com deal was found by Cheapflights users on 1/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 1/175:10 pmSAN - ORD
Nonstop4h 27mAlaska Airlines
lun. 1/269:00 amORD - SAN
Nonstop4h 43mAlaska Airlines
Deal found 1/6$155
This Kiwi.com deal was found by Cheapflights users on 1/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 1/296:30 amSAN - ORD
1 stop10h 01mFrontier
lun. 2/28:00 amORD - SAN
1 stop7h 57mFrontier
Deal found 1/6$156
This Kiwi.com deal was found by Cheapflights users on 1/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 1/3110:34 amSAN - STL
1 stop22h 44mFrontier
lun. 2/21:40 pmSTL - SAN
1 stop12h 28mFrontier
Deal found 1/5$156
This Alaska Airlines deal was found by Cheapflights users on 1/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 2/145:42 pmSAN - ORD
Nonstop4h 17mAlaska Airlines
mié. 2/188:20 amORD - SAN
Nonstop4h 49mAlaska Airlines
Deal found 1/6$157
This Southwest deal was found by Cheapflights users on 1/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 1/296:25 amSAN - MDW
Nonstop4h 00mSouthwest
lun. 2/27:50 pmMDW - SAN
Nonstop4h 30mSouthwest
Deal found 1/8$157
This Kiwi.com deal was found by Cheapflights users on 1/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 2/37:00 amSAN - STL
2 stops38h 33mFrontier
vie. 2/67:39 pmSTL - SAN
1 stop29h 52mFrontier
Deal found 1/5$157

Cheapflights Fare Finder

 
Customize your flight search to find flights from San Diego to Illinois that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated enero 8, 2026.
Use the filters below to find and compare flights from San Diego to Illinois that are best for you.

Fly from

San Diego

Fly to

Illinois

Route

Depart

Return

Price

San DiegoChicago

SAN - ORD

SANORD

San Diego

sáb. 2/14

5:42 pm-11:59 pm

Nonstop4h 17m

Chicago O'Hare Intl

mié. 2/18

8:20 am-11:09 am

Nonstop4h 49m

$157

San DiegoChicago

SAN - ORD

SANORD

San Diego

jue. 2/12

8:35 am-2:58 pm

Nonstop4h 23m

Chicago O'Hare Intl

lun. 2/16

8:20 am-11:09 am

Nonstop4h 49m

$157

San DiegoChicago

SAN - ORD

SANORD

San Diego

mié. 2/18

5:00 pm-11:00 pm

Nonstop4h 00m

Chicago O'Hare Intl

dom. 2/22

7:05 am-9:47 am

Nonstop4h 42m

$167

San DiegoChicago

SAN - MDW

SANMDW

San Diego

mié. 2/25

6:25 am-12:25 pm

Nonstop4h 00m

Chicago Midway

lun. 3/2

8:35 pm-11:05 pm

Nonstop4h 30m

$167

San DiegoChicago

SAN - ORD

SANORD

San Diego

jue. 2/19

2:10 pm-8:19 pm

Nonstop4h 09m

Chicago O'Hare Intl

dom. 2/22

7:05 am-9:47 am

Nonstop4h 42m

$167

San DiegoChicago

SAN - MDW

SANMDW

San Diego

jue. 5/7

6:40 am-12:35 pm

Nonstop3h 55m

Chicago Midway

dom. 5/10

9:10 pm-11:25 pm

Nonstop4h 15m

$167

San DiegoChicago

SAN - ORD

SANORD

San Diego

jue. 2/5

4:47 pm-10:59 pm

Nonstop4h 12m

Chicago O'Hare Intl

dom. 2/8

7:10 am-9:40 am

Nonstop4h 30m

$167

San DiegoChicago

SAN - MDW

SANMDW

San Diego

jue. 1/29

10:30 am-7:55 pm

2 stops7h 25m

Chicago Midway

mié. 2/4

7:50 pm-10:20 pm

Nonstop4h 30m

$172

San DiegoChicago

SAN - MDW

SANMDW

San Diego

jue. 2/19

6:45 am-12:40 pm

Nonstop3h 55m

Chicago Midway

lun. 2/23

8:35 pm-11:05 pm

Nonstop4h 30m

$177

San DiegoChicago

SAN - ORD

SANORD

San Diego

mar. 2/24

10:59 am-11:52 pm

1 stop10h 53m

Chicago O'Hare Intl

mar. 3/10

7:25 am-2:43 pm

1 stop9h 18m

$179

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/8

Showing 1-10 of 60 results
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Best time to book a flight from San Diego to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from San Diego with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from San Diego to Illinois

What is the cheapest month to book a flight from San Diego to Illinois?

Currently, February is the cheapest month in which you can book a flight from San Diego to Illinois (average of $86). Flying from San Diego to Illinois in May is currently the most expensive (average of $176). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SAN to IL?

Find hourly flight availability from San Diego to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated enero 8, 2026.

When flying from San Diego to Illinois, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 31% versus a flight in the morning.

What is the cheapest day to fly from San Diego to Illinois?

Use this chart to determine the cheapest time to fly round-trip from San Diego to Illinois. Price data was last updated on January 3, 2026.

Travelers seeking maximum savings on their San Diego to Illinois flight should consider departing on Friday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from San Diego to Illinois

Explore weekly flight availability from San Diego to Illinois. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated enero 8, 2026.

The most flights from SAN to USIL are scheduled on a Wednesday (29 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (21 on average).

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated enero 8, 2026.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and United Airlines from San Diego to Illinois. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Alaska Airlines
8.0
Very good
11,672 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Southwest
8.0
Very good
4,250 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
United Airlines
7.4
Good
9,142 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
American Airlines
7.2
Good
11,097 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.
Frontier
5.7
Fair
3,061 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Overall

8.0

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Crew

8.5

Food

7.1

Reviews

1 / 20
2.0
Mediocre

Art,Dec 2025

SAN - OGG

It was a five hour flight and my seat did not recline. I have had three back surgeries and I’m solid bone for my L3 vertebrae all the way to my tailbone. My body has never hurt so much. There was no TV on this flight and only a small can of soda was free.

Related info for your journey

Find useful and relevant information for your journey from San Diego to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from San Diego to Illinois?

    Located just 2.6 mi from the city center, San Diego (SAN) is the airport most travelers will use when flying to Illinois from San Diego.

  • How long is the flight from San Diego to Illinois?

    There are many flights that can get you from San Diego to Illinois in 4h. Fly via Alaska Airlines, United Airlines, or Southwest to get the fastest option. There are 1719 mi between San Diego and Illinois. All flights are typically nonstop.

  • What are the cheapest airlines to fly from San Diego to Illinois one-way?

    One-way options have recently been found by users for as low as $45 on Spirit Airlines. Other airlines that offer cheap prices include Frontier from $61 and Southwest from $62 one-way.

  • What are the most popular routes from San Diego to Illinois?

    While some choose either San Diego - Chicago Midway or San Diego - Lambert-St Louis, San Diego - Chicago O'Hare Intl is the most popular route from San Diego to Illinois.

  • What are the most reliable airlines from San Diego to Illinois?

    The top 3 most reliable airlines when flying from San Diego to Illinois are Aer Lingus (98%), Gulf Air (94%) and Cathay Pacific (93%).

  • What are the cheapest flights from San Diego to Illinois?

    While on average a flight from San Diego to Illinois is generally $1,041, our data shows the cheapest flight currently is $82. When looking at the most popular route, (San Diego - Chicago O'Hare Intl), you can expect to pay $128 for that flight.

  • Can I find deals for flights from San Diego to Illinois that include hotel bookings?

    Yes. In addition to deals on San Diego to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from San Diego to Illinois?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from San Diego to Illinois.

  • Can I find deals for business class flights from San Diego to Illinois?

    Yes. Cheapflights offers flight deals from San Diego to Illinois by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from San Diego to Illinois?

    Currently, February is the cheapest month in which you can book a flight from San Diego to Illinois (average of $86). Flying from San Diego to Illinois in May is currently the most expensive (average of $176). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for San Diego to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Top 8 airlines flying from San Diego to Illinois

Discover the top 8 airlines that operate flights from San Diego to Illinois. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated enero 8, 2026.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$99Average$183FlexibilityNo cancel feeOn-time65%
FrontierCheapest$110Average$213FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$139Average$197FlexibilityNo cancel feeOn-time85%
Alaska AirlinesCheapest$139Average$264FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$163Average$455FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$179Average$429FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$205Average$386FlexibilityNo cancel feeOn-time63%
DeltaCheapest$236Average$368FlexibilityNo cancel feeOn-timeN/A

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