Cheap flights from Illinois to Los Angeles from $77
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to Los Angeles departing on 5/20. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
Discover deals from 900+ travel sites with momondo.
Save money when you book flights with momondo
Big names and deals
Big names and deals
Search 100s of travel sites to compare prices.Filter for what you want
Filter for what you want
Free Wi-Fi? Stopover? Instantly customize your results.Trusted and free
Trusted and free
We’re completely free to use - no hidden charges or fees.Price Alerts
Price Alerts
Not ready to book? to track prices.Find the cheapest flights from Illinois to Los Angeles
Cheap round-trip flights
Cheap one-way flights
Cheap last minute flights
Cheap direct flights
Frontier flights from Illinois to Ontario
Our best Frontier deals on Illinois to Ontario flight tickets
Southwest flights from Illinois to Ontario
Our best Southwest deals on Illinois to Ontario flight tickets
See travel insights to Los Angeles from
How to get the cheapest flight ticket from Illinois to Ontario
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Ontario?
In general, November is the cheapest month to fly from Illinois to Ontario. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $148. If you aren’t able to travel during the month of November, then book flights to Ontario from Illinois during September instead. Flights to Ontario in September, while not as cheap as those in November, still average around $166.
What is the cheapest day to depart on your flight to Ontario?
The cheapest day to depart on your flight to Ontario is on a Saturday when prices can be found for as low as $370. This is often the case because there is less demand to fly during this day of the week. When flying out on a Monday, the most expensive travel day of the week, you can expect to see flight prices from Illinois to Ontario for around $492.
What is the cheapest time of day to depart on your flight to Ontario?
In the evening is the cheapest time of day to fly from Illinois to Ontario when you can find flight prices for as low as $318. Flying to Ontario in the evening is an ideal time because this is during off-peak travel hours. If you have a flexible travel schedule, then try to avoid flying at noon when prices are $452 on average. Flights to Ontario from Illinois at noon are generally more expensive because this time of day is more convenient for travelers’ schedules.
What is the cheapest Illinois to Ontario flight route?
Fly from Chicago O'Hare Intl to Ontario for the best Illinois - Ontario flight prices
How far in advance should I book a flight to Ontario?
You are more likely to see cheaper flights to Ontario from Illinois when booking 8 weeks ahead of your departure date. In general, you can expect to find flights to Ontario for around $319 when searching 8 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Ontario from Illinois for as low as $241 on momondo.
What cabin class options are available on Illinois to Ontario flights?
There are 2 cabin classes available to choose from on Illinois to Ontario flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Illinois to Ontario?
Frontier, Southwest, and United Airlines are the most popular carriers operating from Illinois to Ontario
What airlines fly to Ontario?
American Airlines, Spirit Airlines and United Airlines are the top three most popular airlines that fly to Ontario from Illinois according to our data. American Airlines is the first choice among our users, with 44% of people opting to fly with this airline when traveling to Ontario. Keep in mind that there are 9 different airlines that fly to Ontario on a routine basis, so you have a few additional options to choose from.
How many flights depart from Illinois to Ontario on average per week?
5 flights are operational weekly from Illinois to Ontario as of May 2025. The most popular departure day for this route is Mon, with 20% of flights per week taking off on this day.
Cheap Illinois to Ontario flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Illinois to Ontario
When did momondo last update prices for flights from Illinois to Ontario Airport?
Prices for flights from Illinois to Ontario Airport refresh daily.
How many operators does momondo search for flights from Illinois to Ontario Airport?
As of May 2025, there are 5 operators available to choose from for flights from Illinois to Ontario Airport.
How old do you have to be to fly from Illinois to Ontario Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Illinois to Ontario Airport.
What documentation or ID do you need to fly to Ontario Airport?
The travel and health documents required for your trip to Ontario Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Ontario Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Illinois to Ontario?
momondo data reveals that the most frequently booked plane model on the route from Illinois to Ontario is Boeing 737 MAX 8, representing 21.99% of all bookings. The subsequent popular models are Airbus A320neo at 20.78%, Airbus A321neo at 14.46%, and Boeing 737-800 at 10.54%.
Best airlines flying from Illinois to Ontario
Compare and see reviews for airlines that fly from Illinois to Ontario with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $123 | Free Cancellation | Rating 5.9 3,287 reviews | |||
| PriceFrom $204 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $246 | Free Cancellation | Rating 8.0 7,934 reviews | |||
| PriceFrom $246 | Free Cancellation | Rating 7.4 8,696 reviews | |||
| PriceFrom $256 | Free Cancellation | Rating 8.0 4,294 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from Illinois to Ontario?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Illinois to Ontario. momondo saves you time and could save you money on your trip.
Can I find flights from Illinois to Ontario with flexible booking policies on momondo?
All flight searches from Illinois to Ontario on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from Illinois to Ontario?
Once all potential Illinois to Ontario flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from Illinois to Ontario right now. Can momondo alert me if prices change?
Price alerts on flights to Ontario from Illinois are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.