Cheap Flights from Tri-State Airport to Illinois from $303 Roundtrip

Flight deals from Tri-State Airport to Illinois

Looking for a cheap last-minute deal or the best roundtrip flight from Tri-State Airport to Illinois? If you want to travel next month, roundtrip fares start from $321. Find the lowest prices on one-way and roundtrip tickets right here.

Chicago.$303 per passenger.Departing Sat, Jun 27, returning Fri, Jul 3.Round-trip flight with Allegiant Air.Outbound indirect flight with Allegiant Air, departing from Tri-State on Sat, Jun 27, arriving in Chicago Midway.Inbound indirect flight with Allegiant Air, departing from Chicago Rockford on Fri, Jul 3, arriving in Tri-State.Price includes taxes and charges.From $303, select.

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Flying from Tri-State Airport to Illinois

Arm yourself with these facts on the fly.

Cheapest flight found	$303
Cheapest month to fly	June

How to find cheap flights from Tri-State Airport to Illinois

We've compared the best online travel agents and flight providers on the internet to find the cheapest plane tickets from Tri-State Airport to Illinois. Other savvy travelers recently found round-trip flights from $303 and one-way tickets from $183. Ready to join them? Here are a few tips to help you do it the smart way.

Fly in June

The cheapest time to fly from Tri-State Airport to Illinois is currently June.

Flex your dates for the best rates

If you’re flexible on your departure dates, you can use Skyscanner's whole month tool to find the cheapest day of the year to fly from Tri-State Airport to anywhere you choose in Illinois.

Watch as flight prices go up and down

With Price Alerts, we'll let you know when flight prices from Tri-State Airport to your chosen airport in Illinois go up or down so you can book when the time is just right.

Relax – these are fee-free plane tickets

With us, there are no added fees – the Illinois Airport to Illinois flight price you see when you search with us is what you pay to the provider.

Frequently asked questions

Are there any direct flights from Tri-State Airport to Illinois?

There are currently no direct flights from Tri-State Airport to Illinois, but we've found some other routes to United States – check them out now.

What is the average price of a flight from Tri-State Airport to Illinois?

We looked at all of the upcoming round-trip flights from Tri-State Airport to Illinois we could find over the next 12 months. It looks like $303 is the best price. This is good, compared to the average Illinois ticket price of $303.

What is the cheapest month to fly from Tri-State Airport to Illinois?

The cheapest month to fly from Tri-State Airport to Illinois is currently June.

On which upcoming date is it cheapest to fly from Tri-State Airport to Illinois?

After crunching the numbers on our flight calendar, we found that it is currently cheapest to fly from Tri-State Airport to Illinois on Saturday, June 27, 2026.

If I'm flying from Tri-State Airport, where in Illinois is cheapest to fly to?

If you're flying from Tri-State, the cheapest city in Illinois to fly into is Chicago. The cheapest airport serving Chicago at the moment is Chicago Midway.