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$72+ 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 5/4. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SAN
may. 12 — may. 191
mar. 5/12
mar. 5/19
1 adult, Economy
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Cheap 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 abril 12, 2026.

This Kiwi.com deal was found by Cheapflights users on 4/7. 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.
lun. 4/277:50 am
ORD
-
SAN
2 stops31h 27m
Frontier
sáb. 5/211:42 am
SAN
-
ORD
1 stop20h 03m
Frontier
Deal found 4/7$197
This Kiwi.com deal was found by Cheapflights users on 4/7. 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. 4/306:09 pm
ORD
-
SAN
1 stop7h 35m
Frontier
jue. 5/76:25 am
SAN
-
ORD
1 stop12h 07m
Frontier
Deal found 4/7$200
This Kiwi.com deal was found by Cheapflights users on 4/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 5/269:37 pm
ORD
-
SAN
1 stop28h 13m
Frontier
mar. 6/26:25 am
SAN
-
ORD
1 stop12h 07m
Frontier
Deal found 4/9$201
This Kiwi.com deal was found by Cheapflights users on 4/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 5/37:45 am
ORD
-
SAN
1 stop26h 01m
Multiple Airlines
mié. 5/66:25 am
SAN
-
ORD
1 stop27h 39m
Multiple Airlines
Deal found 4/8$202
This Kiwi.com deal was found by Cheapflights users on 4/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 5/19:00 am
ORD
-
SAN
2 stops31h 24m
Multiple Airlines
mar. 5/56:25 am
SAN
-
ORD
1 stop30h 38m
Multiple Airlines
Deal found 4/9$203
This Kiwi.com deal was found by Cheapflights users on 4/7. 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.
mié. 4/298:25 am
ORD
-
SAN
2 stops16h 41m
Frontier
sáb. 5/211:42 am
SAN
-
ORD
1 stop20h 03m
Frontier
Deal found 4/7$204
This Frontier deal was found by Cheapflights users on 4/7. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 5/69:37 pm
ORD
-
SAN
1 stop13h 05m
Frontier
lun. 5/116:25 am
SAN
-
ORD
1 stop12h 07m
Frontier
Deal found 4/7$205
This Kiwi.com deal was found by Cheapflights users on 4/11. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 5/26:00 am
MDW
-
SAN
2 stops28h 34m
Frontier
mié. 5/66:25 am
SAN
-
MDW
1 stop29h 47m
Frontier
Deal found 4/11$206
This Kiwi.com deal was found by Cheapflights users on 4/7. 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. 4/306:09 pm
ORD
-
SAN
1 stop7h 35m
Frontier
mar. 5/54:17 pm
SAN
-
ORD
2 stops12h 22m
Frontier
Deal found 4/7$206
This Frontier deal was found by Cheapflights users on 4/9. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 5/169:37 pm
ORD
-
SAN
1 stop13h 05m
Frontier
lun. 5/186:25 am
SAN
-
ORD
1 stop12h 07m
Frontier
Deal found 4/9$207
This Kiwi.com deal was found by Cheapflights users on 4/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 4/308:25 am
MDW
-
SAN
1 stop17h 19m
Frontier
mar. 5/56:25 am
SAN
-
MDW
1 stop29h 47m
Frontier
Deal found 4/10$208
This Kiwi.com deal was found by Cheapflights users on 4/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 5/46:09 pm
ORD
-
SAN
1 stop25h 50m
Frontier
lun. 5/116:25 am
SAN
-
ORD
1 stop27h 15m
Frontier
Deal found 4/10$208

Find 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 abril 12, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$176
(Kiwi.com)

One-way from

$72
(Kiwi.com)

Popular in

March

Cheapest in

October

Average price

$297

Good round-trip deal

$301 or less

Good one-way deal

$158 or less
Provider with most accurate pricing for Chicago (CHI)-San Diego flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-San Diego flights.
Search Deals
From Illinois to San Diego
Search Deals
One-way flight from Illinois to San Diego
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($18 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from Illinois to San Diego.
Search Deals
Price to beat on a one-way flight from Illinois to San Diego.
Search Deals

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 abril 12, 2026.
Use the filters below to find and compare flights from Illinois to San Diego that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

sáb. 5/23

7:00 am-9:28 am

Nonstop4h 28m

San Diego

mar. 5/26

10:40 pm-4:49 am

Nonstop4h 09m

$237

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

mié. 5/27

2:11 pm-6:45 pm

1 stop6h 34m

San Diego

mar. 6/9

6:20 am-5:02 pm

1 stop8h 42m

$257

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

vie. 5/1

3:52 pm-6:31 pm

Nonstop4h 39m

San Diego

mar. 5/5

7:03 am-1:13 pm

Nonstop4h 10m

$267

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

sáb. 5/23

7:59 pm-10:36 pm

Nonstop4h 37m

San Diego

jue. 5/28

7:00 am-1:14 pm

Nonstop4h 14m

$267

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

mié. 5/20

7:05 am-9:42 am

Nonstop4h 37m

San Diego

lun. 5/25

6:40 am-1:09 pm

Nonstop4h 29m

$267

ChicagoSan Diego

MDW - SAN

MDWSAN

Chicago Midway

vie. 5/1

5:25 pm-7:45 pm

Nonstop4h 20m

San Diego

sáb. 5/2

7:40 am-6:15 pm

1 stop8h 35m

$277

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

mar. 5/26

7:45 pm-11:43 pm

1 stop5h 58m

San Diego

dom. 5/31

10:15 pm-8:45 am

1 stop8h 30m

$287
Quickest round-trip

ChicagoSan Diego

MDW - SAN

MDWSAN

Chicago Midway

vie. 5/15

5:25 pm-7:45 pm

Nonstop4h 20m

San Diego

vie. 5/22

10:40 pm-4:35 am

Nonstop3h 55m

$297

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

jue. 5/21

2:10 pm-4:48 pm

Nonstop4h 38m

San Diego

dom. 5/31

5:44 pm-11:55 pm

Nonstop4h 11m

$297

ChicagoSan Diego

ORD - SAN

ORDSAN

Chicago O'Hare Intl

vie. 5/8

8:50 am-11:30 am

Nonstop4h 40m

San Diego

jue. 5/14

7:00 am-1:14 pm

Nonstop4h 14m

$297

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/7

Showing 1-10 of 60 resultsSorted by cheapest first
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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, September is the cheapest month in which you can book a flight from Illinois to San Diego (average of $89). Flying from Illinois to San Diego in March is currently the most expensive (average of $167). 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 abril 12, 2026.

A simple way to save on the total cost of your ticket is to fly from Illinois to San Diego in the evening. If you’re flexible enough to do this you can expect to save up to 24% on your trip compared to booking a flight at noon.

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

Use this chart to determine the cheapest time to fly round-trip from Illinois to San Diego. Price data was last updated on April 4, 2026.

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

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 abril 12, 2026.

The most flights from USIL to SAN are scheduled on a Sunday (44 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (29 on average).

How much does it cost to fly round-trip from Illinois to San Diego?

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.

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

    For as low as $237, United Airlines can have you in San Diego from Illinois in 4h 28m. Illinois and San Diego are separated by a distance of 1719 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    To fly one-way, consider booking your trip with Spirit Airlines, which is currently one of the cheapest options available, starting at $43. Frontier flights start at $57 while deals on Hawaiian Airlines start at $69 one-way.

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

    Most travelers choose Chicago O'Hare Intl - San Diego, Lambert-St Louis - San Diego or Chicago Midway - San Diego when deciding on the best route from Illinois to San Diego.

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

    Consider Air Canada (82%), United Airlines (80%) or SWISS (78%) 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 $98. On average you can expect to pay $589. The most popular route, (Chicago O'Hare Intl - San Diego), can usually be booked for $168.

  • 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, September is the cheapest month in which you can book a flight from Illinois to San Diego (average of $89). Flying from Illinois to San Diego in March is currently the most expensive (average of $167). 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 San Diego?

Book flights to San Diego if you plan to visit one of these locations
El Cajon
Chula Vista
National City
Coronado
La Mesa
Poway
Julian
Lemon Grove

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Alternative routes for Illinois to San Diego

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Top 9 airlines flying from Illinois to San Diego

Discover the top 9 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 abril 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$84Average$183FlexibilityNo cancel feeOn-time65%
FrontierCheapest$97Average$225FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$138Average$240FlexibilityNo cancel feeOn-time85%
Alaska AirlinesCheapest$147Average$285FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$157Average$432FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$157Average$377FlexibilityNo cancel feeOn-time69%
JetBlueCheapest$167Average$358FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$332FlexibilityNo cancel feeOn-time63%
DeltaCheapest$237Average$297FlexibilityNo cancel feeOn-timeN/A

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