San Diego

$88+ Cheap flights from Illinois to San Diego (SAN)

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 5/24. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SAN
Apr 27 — May 41
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Cheap flight deals from Illinois to San Diego

Keep the following information in mind while searching for Illinois to San Diego flight deals. Data was last updated April 22, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$185
(Mytrip)

One-way from

$88
(Cheapflightsfares)

Popular in

March

Cheapest in

February

Average price

$387

Good round-trip deal

$273 or less

Good one-way deal

$164 or less
Provider with most accurate pricing for Chicago (CHI)-San Diego flight deals.
Provider most trusted by Cheapflights users for Chicago (CHI)-San Diego flights.
From Illinois to San Diego
One-way flight from Illinois to San Diego
Highest demand for flights based on searches. 0% potential increase in price ($3 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Average for round-trip flights in April 2025
Price to beat on a round-trip flight from Illinois to San Diego.
Price to beat on a one-way flight from Illinois to San Diego.

Find flight deals from Illinois to San Diego

Cheapest flights from Illinois to San Diego
Explore the most affordable flight options available from Illinois to San Diego. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 22, 2025.

This Frontier deal was found by Cheapflights users on 4/22. 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.
Wed 7/301:40 pmORD - SAN
Nonstop4h 20mFrontier
Tue 8/54:53 pmSAN - ORD
Nonstop4h 23mFrontier
Deal found 4/22$187
This Frontier deal was found by Cheapflights users on 4/22. 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.
Fri 5/306:25 amMDW - SAN
1 stop7h 31mFrontier
Tue 6/36:25 amSAN - MDW
1 stop12h 28mFrontier
Deal found 4/22$188
This Mytrip deal was found by Cheapflights users on 4/22. 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.
Tue 5/209:02 pmORD - SAN
1 stop12h 11mSpirit Airlines
Tue 5/278:08 amSAN - ORD
2 stops20h 34mSpirit Airlines
Deal found 4/22$189
This Mytrip deal was found by Cheapflights users on 4/22. 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.
Sat 6/1411:50 amORD - SAN
1 stop13h 39mMultiple Airlines
Tue 6/174:53 pmSAN - ORD
Nonstop4h 03mMultiple Airlines
Deal found 4/22$194
This American Airlines deal was found by Cheapflights users on 4/22. 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.
Sun 5/255:05 pmPIA - SAN
1 stop8h 54mAmerican Airlines
Thu 5/291:48 pmSAN - PIA
1 stop8h 08mAmerican Airlines
Deal found 4/22$229
This Southwest deal was found by Cheapflights users on 4/22. 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.
Wed 6/117:35 amMDW - SAN
Nonstop4h 15mSouthwest
Wed 6/186:55 pmSAN - MDW
Nonstop3h 55mSouthwest
Deal found 4/22$237
This American Airlines deal was found by Cheapflights users on 4/22. 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.
Sat 5/315:00 amMLI - SAN
1 stop7h 59mAmerican Airlines
Wed 6/410:19 amSAN - MLI
1 stop9h 26mAmerican Airlines
Deal found 4/22$240
This United Airlines deal was found by Cheapflights users on 4/22. 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.
Sat 5/315:40 pmMLI - SAN
1 stop6h 34mUnited Airlines
Wed 6/49:30 pmSAN - MLI
2 stops10h 50mUnited Airlines
Deal found 4/22$245
This Delta deal was found by Cheapflights users on 4/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/216:05 pmSTL - SAN
1 stop7h 42mDelta
Tue 5/276:20 amSAN - STL
1 stop8h 40mDelta
Deal found 4/22$257
This United Airlines deal was found by Cheapflights users on 4/22. 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.
Tue 7/18:54 amSTL - SAN
1 stop5h 58mUnited Airlines
Tue 8/510:54 amSAN - STL
2 stops7h 42mUnited Airlines
Deal found 4/22$262
This Trip.com deal was found by Cheapflights users on 4/21. 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.
Mon 5/196:53 pmSTL - SAN
2 stops30h 26mFrontier
Sat 5/246:52 pmSAN - STL
1 stop16h 48mFrontier
Deal found 4/21$263
This Mytrip deal was found by Cheapflights users on 4/22. 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.
Sat 5/2410:10 amSTL - SAN
2 stops23h 03mSpirit Airlines
Wed 5/286:15 amSAN - STL
2 stops25h 00mSpirit Airlines
Deal found 4/22$269

Cheapflights Fare Finder

Customize your flight search to find flights from Illinois to San Diego 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 April 22, 2025.
Use the filters below to find and compare flights from Illinois to San Diego that are best for you.

Fly from

Illinois

Fly to

San Diego

Route

Depart

Return

Price

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

Sat 6/14

9:35 pm-7:13 am

1 stop11h 38m

San Diego

Tue 6/17

4:53 pm-10:56 pm

Nonstop4h 03m

$185

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

Sat 7/5

1:40 pm-4:00 pm

Nonstop4h 20m

San Diego

Wed 7/9

4:53 pm-11:16 pm

Nonstop4h 23m

$186

ChicagoSan Diego

MDW - SAN

MDWSAN

Chicago Midway

Fri 5/30

6:25 am-11:56 am

1 stop7h 31m

San Diego

Tue 6/3

6:25 am-8:53 pm

1 stop12h 28m

$188

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

Sat 5/17

4:35 pm-7:13 am

2 stops16h 38m

San Diego

Wed 5/21

8:48 pm-5:25 am

1 stop6h 37m

$189

PeoriaSan Diego

PIA - SAN

PIASAN

Greater Peoria

Sun 5/25

5:05 pm-11:59 pm

1 stop8h 54m

San Diego

Thu 5/29

1:48 pm-11:56 pm

1 stop8h 08m

$229

ChicagoSan Diego

MDW - SAN

MDWSAN

Chicago Midway

Wed 6/11

7:35 am-9:50 am

Nonstop4h 15m

San Diego

Wed 6/18

6:55 pm-12:50 am

Nonstop3h 55m

$237

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

Sat 5/24

4:55 pm-7:16 pm

Nonstop4h 21m

San Diego

Tue 5/27

2:49 pm-9:06 pm

Nonstop4h 17m

$237

MolineSan Diego

MLI - SAN

MLISAN

Moline Quad-City

Sat 5/31

5:00 am-10:59 am

1 stop7h 59m

San Diego

Wed 6/4

10:19 am-9:45 pm

1 stop9h 26m

$240

MolineSan Diego

MLI - SAN

MLISAN

Moline Quad-City

Sat 5/31

5:40 pm-10:14 pm

1 stop6h 34m

San Diego

Wed 6/4

9:30 pm-10:20 am

2 stops10h 50m

$245

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

Sat 5/24

3:43 pm-8:37 pm

1 stop6h 54m

San Diego

Fri 5/30

6:15 am-4:30 pm

1 stop8h 15m

$257

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/22

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

Have a flexible travel schedule? Discover the best time to fly to San Diego from Illinois 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 Illinois to San Diego

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

Currently, August is the cheapest month in which you can book a flight from Illinois to San Diego (average of $286). Flying from Illinois to San Diego in March is currently the most expensive (average of $366). 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 IL to SAN?

Find hourly flight availability from Illinois to San Diego. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated April 22, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to San Diego as you normally would.

Weekly flight availability from Illinois to San Diego

Explore weekly flight availability from Illinois to San Diego. 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 April 22, 2025.

The most flights from USIL to SAN are scheduled on a Tuesday (40 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (23 on average).

Rainfall in San Diego by month

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

In terms of precipitation, rainfall in San Diego ranges from 0.0 - 2.3 inches per month. February is typically the wettest month, when rainfall can reach 2.3 in. July is typically the driest time to visit San Diego when rainfall is around 0.0 in.

Temperature in San Diego by month

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

If weather is an important factor for your trip to San Diego, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 71.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 57.2 F).

Reviews of airlines servicing San Diego

Get insights into the airlines that provide service to San Diego. 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 San Diego. Reviews last updated April 22, 2025.
To help decide which airline to fly from Illinois to San Diego, see what other customers have to say about Alaska Airlines, Southwest and Delta. 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.

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
8.0
Very good

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Related info for your journey

Find useful and relevant information for your journey from Illinois to San Diego. 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 into for flights to San Diego from Illinois?

    Most people fly into San Diego (SAN) if they book a flight to San Diego from Illinois. San Diego is conveniently located just 2.6 mi from San Diego’s city center.

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

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $88. Spirit Airlines flights start at $92 while deals on Allegiant Air start at $112 one-way.

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

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

    Consider Japan Airlines (100%), Air Canada (88%) or Brussels Airlines (85%) when booking your flight. These represent the most reliable airlines when flying from Illinois to San Diego.

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

    The cheapest flight price from Illinois to San Diego is $118. On average you can expect to pay $734. The most popular route, (Chicago O'Hare Intl - San Diego), can usually be booked for $159.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Illinois to San Diego 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 Illinois to San Diego?

    Currently, August is the cheapest month in which you can book a flight from Illinois to San Diego (average of $286). Flying from Illinois to San Diego in March is currently the most expensive (average of $366). 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

Traveling to a place near Illinois?

Book flights to Illinois if you plan to visit one of these locations
El Cajon
Chula Vista
Lemon Grove
National City
Imperial Beach
La Mesa
Alpine
Poway
Santee
Coronado

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Alternative routes for Illinois to San Diego

See prices for flight routes from nearby airports that may be better suited for you.

Top 7 airlines flying from Illinois to San Diego

Discover the top 7 airlines that operate flights from Illinois to San Diego. 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 April 22, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$102Average$216FlexibilityNo cancel feeOn-time65%
FrontierCheapest$108Average$198FlexibilityNo cancel feeOn-time62%
DeltaCheapest$144Average$413FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$204Average$475FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$217Average$437FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$254Average$461FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$403Average$653FlexibilityNo cancel feeOn-time75%

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