Chicago to Ontario MDW, ORD → ONT
Chicago Midway International Airport (MDW), O'Hare International Airport (ORD) → Ontario International Airport (ONT)
The cheapest return found recently is $252 with Frontier Airlines, 21 Oct – 5 Nov, found yesterday. The cheapest one-way found recently is $135 with Frontier Airlines, 25 Jan 2027, found yesterday.
Return
The cheapest return fare on each of 11 departure dates is usually $247 to $290.
Cheapest return found recently
$252
21 Oct – 5 Nov · Frontier Airlines
O'Hare International Airport (ORD) → Ontario International Airport (ONT)
Leaves 6:30 a.m. · Return leaves 8:35 p.m. · 12 h 37 min of travel, both ways together
out 1 stop, back 1 stop
found yesterday
Cheapest nonstop return
None seen yet.
Found recently, and the cheapest we hold
$252 21 Oct – 5 Novfound yesterdaySee prices for these dates
$223 22 Oct – 29 Octfound 4 days agoSee prices for these dates
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest return we saw each day was $145 to $229.
At $252, the cheapest return found recently is above that range.
25 days is a short history, so treat this range as an early guide.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 11 departure dates from 20 Oct to 3 Jan 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 15-night return fares leaving within 3 days of 21 Oct to compare.
Every date we hold
26 fares on 11 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 20 Oct – 5 Nov | $253 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 21 Oct – 5 Nov | $252 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 22 Oct – 29 Oct | $223 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found 4 days ago | See prices for these dates |
| 23 Oct – 8 Nov | $274 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 24 Oct – 14 Nov | $225 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
| 30 Oct – 2 Nov | $241 | Frontier Airlines | Chicago Midway International Airport (MDW) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found 4 days ago | See prices for these dates |
| 3 Nov – 14 Nov | $291 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back nonstop | found yesterday | See prices for these dates |
| 12 Nov – 21 Nov | $289 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back nonstop | found 2 days ago | See prices for these dates |
| 20 Nov – 29 Nov | $370 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 23 Nov – 25 Nov | $265 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
| 3 Jan 2027 – 10 Jan 2027 | $347 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | out 1 stop, back nonstop | found 2 days ago | See prices for these dates |
Which month looks cheapest?
October 2026 is the cheapest month — from $223.
Airlines on the cheapest dates: Frontier Airlines.
One-way
The cheapest one-way fare on each of 8 departure dates is usually $112 to $159.
Cheapest one-way found recently
$135
25 Jan 2027 · Frontier Airlines
O'Hare International Airport (ORD) → Ontario International Airport (ONT)
Leaves 6:21 a.m. · 6 h 26 min trip
1 stop
found yesterday
Cheapest nonstop one-way
$150
25 Jan 2027 · Southwest Airlines
Chicago Midway International Airport (MDW) → Ontario International Airport (ONT)
Leaves 3:50 p.m. · 4 h 20 min trip
nonstop
found yesterday
Found recently, and the cheapest we hold
$135 25 Jan 2027found yesterdayOpen this trip
$107 4 Novfound 6 days agoOpen this trip
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest one-way we saw each day was $97 to $135.
At $135, the cheapest one-way found recently is at the high end of that range.
25 days is a short history, so treat this range as an early guide.
Those were the prices on those days, not today's.
Is this a good one-way price?
Compared with the cheapest one-way fare on each of 8 departure dates from 25 Oct to 25 Jan 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other one-way fares leaving within 3 days of 25 Jan 2027 to compare.
Every date we hold
9 fares on 8 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 25 Oct | $156 | Southwest Airlines | Chicago Midway International Airport (MDW) → Ontario International Airport (ONT) | 1 stop | found 4 days ago | Open this trip |
| 29 Oct | $114 | Frontier Airlines | Chicago Midway International Airport (MDW) → Ontario International Airport (ONT) | 1 stop | found 4 days ago | Open this trip |
| 30 Oct | $113 | Frontier Airlines | Chicago Midway International Airport (MDW) → Ontario International Airport (ONT) | 1 stop | found 4 days ago | Open this trip |
| 4 Nov | $107 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | 1 stop | found 6 days ago | Open this trip |
| 10 Nov | $110 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | 1 stop | found 6 days ago | Open this trip |
| 31 Dec | $172 | Southwest Airlines | Chicago Midway International Airport (MDW) → Ontario International Airport (ONT) | 2 stops | found yesterday | Open this trip |
| 3 Jan 2027 | $169 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | 1 stop | found 2 days ago | Open this trip |
| 25 Jan 2027 | $135 | Frontier Airlines | O'Hare International Airport (ORD) → Ontario International Airport (ONT) | 1 stop | found yesterday | Open this trip |
Which month looks cheapest?
November 2026 is the cheapest month — from $107.
Airlines on the cheapest dates: Frontier Airlines, Southwest Airlines.
Premium cabin fares from Chicago to Ontario
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 21 Oct – 5 Nov in another cabin: Premium economy · Business · First
Today's prices for 25 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Chicago to Ontario?
Return
Fares 30 to 59 days before departure were typically 13% lower than 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 18 Oct (25 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $246 | $145 | +15% | 24 |
| 7–13 days | $246 | $145 | +15% | 25 |
| 14–29 days | $229 | $214 | +7% | 17 |
| 30–59 days | $214 | $197 | Cheapest seen | 22 |
| 60–89 days | $347 | $202 | +63% | 12 |
One-way
Fares 90 to 179 days before departure were typically 14% lower than 0 to 6 days before departure.
From the cheapest one-way each day between 24 Sept and 18 Oct (25 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $121 | $111 | +16% | 25 |
| 7–13 days | $133 | $113 | +28% | 19 |
| 14–29 days | $109 | $97 | +4% | 16 |
| 90–179 days | $104 | $102 | Cheapest seen | 21 |
| 180+ days | $160 | $160 | +54% | 8 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Chicago → Los Angeles
56 km from Ontario
$253
$1 more than flying to Ontario
30 Nov – 15 Dec · MDW → LAX · out 1 stop, back 1 stop
found 6 hours ago
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
Chicago → Los Angeles
56 km from Ontario
$163
$28 more than flying to Ontario
31 Dec · ORD → LAX · nonstop
found yesterday
Cheapest recent price on each route — one way, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 21 Oct – 5 Nov. A live search on this page shows what those dates cost now, for one adult in economy.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work