Illinois

$91+ 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 8/2. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ORD
jun. 17 — jun. 241
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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 junio 12, 2025.

Round-trip from

$172
(FlightHub)

One-way from

$91
(FlightHub)

Popular in

December

Cheapest in

June

Average price

$317

Good round-trip deal

$278 or less

Good one-way deal

$156 or less
From San Diego to Illinois
One-way flight from San Diego to Illinois
Highest demand for flights based on searches. 10% potential increase in price ($44 potential increase over avg. RT price).
Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
Average for round-trip flights in June 2025
Price to beat on a round-trip flight from San Diego to Illinois.
Price to beat on a one-way flight from San Diego to Illinois.

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 junio 12, 2025.

This FlightHub deal was found by Cheapflights users on 6/10. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 7/87:31 pmSAN - ORD
1 stop8h 32mSpirit Airlines
mar. 7/153:18 pmORD - SAN
1 stop9h 48mSpirit Airlines
Deal found 6/10$172
This FlightHub deal was found by Cheapflights users on 6/10. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 7/35:50 pmSAN - ORD
1 stop10h 22mMultiple Airlines
mié. 7/91:39 pmORD - SAN
Nonstop4h 20mMultiple Airlines
Deal found 6/10$174
This FlightHub deal was found by Cheapflights users on 6/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 7/224:44 pmSAN - ORD
Nonstop4h 23mFrontier
jue. 7/311:39 pmORD - SAN
Nonstop4h 20mFrontier
Deal found 6/11$175
This American Airlines deal was found by Cheapflights users on 6/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 8/2910:45 pmSAN - ORD
Nonstop4h 09mAmerican Airlines
mar. 9/29:55 amORD - SAN
Nonstop4h 20mAmerican Airlines
Deal found 6/11$186
This Southwest deal was found by Cheapflights users on 6/9. 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. 8/76:30 pmSAN - MDW
Nonstop4h 00mSouthwest
mar. 8/128:20 amMDW - SAN
Nonstop4h 10mSouthwest
Deal found 6/9$186
This Alaska Airlines deal was found by Cheapflights users on 6/10. 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.
mié. 8/207:45 pmSAN - ORD
1 stop9h 18mAlaska Airlines
mar. 10/78:20 amORD - SAN
Nonstop5h 00mAlaska Airlines
Deal found 6/10$219
This Mytrip deal was found by Cheapflights users on 6/12. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 7/311:55 amSAN - STL
1 stop27h 09mSpirit Airlines
lun. 7/77:13 pmSTL - SAN
2 stops25h 13mSpirit Airlines
Deal found 6/12$226
This CheapOair deal was found by Cheapflights users on 6/10. 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.
jue. 10/2312:03 pmSAN - MDW
1 stop8h 35mFrontier
lun. 10/274:29 pmMDW - SAN
1 stop9h 21mFrontier
Deal found 6/10$235
This American Airlines deal was found by Cheapflights users on 6/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 8/306:15 amSAN - MLI
1 stop8h 43mAmerican Airlines
dom. 8/316:04 amMLI - SAN
1 stop6h 17mAmerican Airlines
Deal found 6/12$240
This Frontier deal was found by Cheapflights users on 6/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 9/49:03 pmSAN - STL
1 stop10h 04mFrontier
mar. 9/97:52 pmSTL - SAN
1 stop5h 58mFrontier
Deal found 6/12$250
This United Airlines deal was found by Cheapflights users on 6/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/265:01 pmSAN - ORD
Nonstop4h 13mUnited Airlines
mar. 10/74:10 pmORD - SAN
Nonstop4h 20mUnited Airlines
Deal found 6/10$251
This Southwest deal was found by Cheapflights users on 6/10. 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.
vie. 8/291:20 pmSAN - ORD
1 stop7h 00mSouthwest
mar. 9/21:50 pmORD - SAN
1 stop9h 55mSouthwest
Deal found 6/10$256

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 junio 12, 2025.
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

mar. 7/8

7:31 pm-6:03 am

1 stop8h 32m

Chicago O'Hare Intl

mar. 7/15

3:18 pm-11:06 pm

1 stop9h 48m

$172

San DiegoChicago

SAN - ORD

SANORD

San Diego

jue. 7/3

5:50 pm-6:12 am

1 stop10h 22m

Chicago O'Hare Intl

mié. 7/9

1:39 pm-3:59 pm

Nonstop4h 20m

$174

San DiegoChicago

SAN - ORD

SANORD

San Diego

mar. 7/22

4:44 pm-11:07 pm

Nonstop4h 23m

Chicago O'Hare Intl

jue. 7/31

1:39 pm-3:59 pm

Nonstop4h 20m

$175

San DiegoChicago

SAN - ORD

SANORD

San Diego

vie. 8/29

10:45 pm-4:54 am

Nonstop4h 09m

Chicago O'Hare Intl

mar. 9/2

9:55 am-12:15 pm

Nonstop4h 20m

$186

San DiegoChicago

SAN - MDW

SANMDW

San Diego

jue. 8/7

6:30 pm-12:30 am

Nonstop4h 00m

Chicago Midway

mar. 8/12

8:20 am-10:30 am

Nonstop4h 10m

$186

San DiegoChicago

SAN - ORD

SANORD

San Diego

lun. 9/15

5:01 pm-11:14 pm

Nonstop4h 13m

Chicago O'Hare Intl

mié. 9/17

1:30 pm-3:50 pm

Nonstop4h 20m

$211

San DiegoChicago

SAN - ORD

SANORD

San Diego

mié. 8/20

7:45 pm-7:03 am

1 stop9h 18m

Chicago O'Hare Intl

sáb. 10/4

10:00 am-1:00 pm

Nonstop5h 00m

$219

San DiegoSt. Louis

SAN - STL

SANSTL

San Diego

jue. 7/3

11:55 am-5:04 pm

1 stop27h 09m

Lambert-St Louis

lun. 7/7

7:13 pm-6:26 pm

2 stops25h 13m

$226

San DiegoMoline

SAN - MLI

SANMLI

San Diego

sáb. 8/30

6:15 am-4:58 pm

1 stop8h 43m

Moline Quad-City

dom. 8/31

6:04 am-10:21 am

1 stop6h 17m

$240

San DiegoSt. Louis

SAN - STL

SANSTL

San Diego

jue. 9/4

9:03 pm-9:07 am

1 stop10h 04m

Lambert-St Louis

mar. 9/9

7:52 pm-11:50 pm

1 stop5h 58m

$250

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

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, August is the cheapest month in which you can book a flight from San Diego to Illinois (average of $245). Flying from San Diego to Illinois in March is currently the most expensive (average of $321). 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 junio 12, 2025.

When flying from San Diego to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 junio 12, 2025.

The most flights from SAN to USIL are scheduled on a Tuesday (50 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (31 on average).

Rainfall in Illinois by month

Plan your trip to Illinois by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Illinois ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Illinois when rainfall is around 1.7 in.

Temperature in Illinois by month

Plan your trip to Illinois by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Illinois, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

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 junio 12, 2025.
To help decide which airline to fly from San Diego to Illinois, see what other customers have to say about Breeze Airways, Alaska Airlines and Southwest. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!
8.0
Very good

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

Crew

8.8

Overall

8.1

Food

6.7

Comfort

8.2

Entertainment

6.6

Boarding

8.3

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

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.

  • 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 $91 on Spirit Airlines. Other airlines that offer cheap prices include Frontier from $99 and United Airlines from $106 one-way.

  • What are the most popular routes 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 Royal Jordanian (96%), Aer Lingus (96%) and Qatar Airways (94%).

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

    While on average a flight from San Diego to Illinois is generally $1,208, our data shows the cheapest flight currently is $102. When looking at the most popular route, (San Diego - Chicago O'Hare Intl), you can expect to pay $118 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, August is the cheapest month in which you can book a flight from San Diego to Illinois (average of $245). Flying from San Diego to Illinois in March is currently the most expensive (average of $321). 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

Browse thousands of different options on Cheapflights for your next trip

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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.

Top 7 airlines flying from San Diego to Illinois

Discover the top 7 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 junio 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$92Average$188FlexibilityNo cancel feeOn-time65%
FrontierCheapest$109Average$200FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$217Average$475FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$238Average$494FlexibilityNo cancel feeOn-time69%
DeltaCheapest$258Average$357FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$306Average$457FlexibilityNo cancel feeOn-time63%
Alaska AirlinesCheapest$391Average$751FlexibilityNo cancel feeOn-time75%

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