What are the cheapest airlines to fly from Orange County to Illinois one-way?

To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $63. Southwest flights start at $144 while deals on American Airlines start at $144 one-way.

Weekly flight availability from Orange County to Illinois

The most flights from zzKFI to USIL are scheduled on a Wednesday (24 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (8 on average).

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.

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).

Can I find deals for flights from Orange County to Illinois that include hotel bookings?

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

How can I find direct flights from Orange County to Illinois?

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

Can I find deals for business class flights from Orange County to Illinois?

Yes. Cheapflights offers flight deals from Orange County 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.

Find Cheap Flights from Orange County to Illinois

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Find flight deals from Orange County to Illinois

Most accurate provider	FlightHub 3 stars
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Popular in	June
Cheapest in	November
Average price	$315

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Highest demand for flights based on searches. 10% potential increase in price ($41 potential increase over avg. RT price).

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Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).

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Average for round-trip flights in October 2026

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Everything you need to know about your flight from Orange County to Illinois

Prices

Airlines

How far ahead should I book a flight from Orange County to Illinois?

Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Orange County to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Orange County to Illinois?

Currently, February is the cheapest month in which you can book a flight from Orange County to Illinois (average of $424). Flying from Orange County to Illinois in June is currently the most expensive (average of $507). 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 KFI to IL?

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

Reviews of airlines servicing Illinois

Read reviews from past customers who have flown Southwest,Alaska Airlines, andUnited Airlines from Orange County to Illinois. 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.

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Southwest

8.0

Very good

4,208 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Alaska Airlines

7.9

Good

13,003 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

United Airlines

7.4

Good

10,271 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

American Airlines

7.0

Good

12,105 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Frontier

5.6

Fair

2,564 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

6.0

Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Related info for your journey

What are the cheapest airlines to fly from Orange County to Illinois one-way?
To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $63. Southwest flights start at $144 while deals on American Airlines start at $144 one-way.
Can I find deals for flights from Orange County to Illinois that include hotel bookings?
Yes. In addition to deals on Orange County to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Orange County to Illinois?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Orange County to Illinois.
Can I find deals for business class flights from Orange County to Illinois?
Yes. Cheapflights offers flight deals from Orange County 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 Orange County to Illinois?
Currently, February is the cheapest month in which you can book a flight from Orange County to Illinois (average of $424). Flying from Orange County to Illinois in June is currently the most expensive (average of $507). 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.

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Top 6 airlines flying from Orange County to Illinois

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$158	Average$260	FlexibilityNo cancel fee	On-time62%
JetBlue	Cheapest$258	Average$411	FlexibilityNo cancel fee	On-time62%
American Airlines	Cheapest$275	Average$541	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$288	Average$504	FlexibilityNo cancel fee	On-time63%
United Airlines	Cheapest$289	Average$509	FlexibilityNo cancel fee	On-time69%
Alaska Airlines	Cheapest$359	Average$569	FlexibilityNo cancel fee	On-time75%

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Cheap flights from Orange County to Illinois

Find cheap flights from Orange County to Illinois with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Find flight deals from Orange County to Illinois

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Popular in

Cheapest in

Average price

Cheapflights Insights

How far ahead should I book a flight from Orange County to Illinois?

Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Orange County to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Orange County to Illinois?

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

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

Weekly flight availability from Orange County to Illinois

The most flights from zzKFI to USIL are scheduled on a Wednesday (24 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (8 on average).

Reviews of airlines servicing Illinois

Read reviews from past customers who have flown Southwest,Alaska Airlines, andUnited Airlines from Orange County to Illinois. 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.

Related info for your journey

What are the cheapest airlines to fly from Orange County to Illinois one-way?

Can I find deals for flights from Orange County to Illinois that include hotel bookings?

How can I find direct flights from Orange County to Illinois?

Can I find deals for business class flights from Orange County to Illinois?

What is the cheapest month to book a flight from Orange County to Illinois?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Orange County to Illinois

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

Complete your trip

Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.

Search flights from Orange County to Illinois by cabin class

Find flights from Orange County to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Orange County and Illinois flights

Browse other Orange County and Illinois flight options. Last updated on October 2, 2026.

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Top 6 airlines flying from Orange County to Illinois

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