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Cheap flights from Ontario to United States
Easily compare round-trip flights from Ontario to United States
Below you can see the best fares for your round-trip flight route over the next three months. All fares were found on momondo this week. Browse the quickest and cheapest flights from Ontario to United States by changing tabs
Quickest
Cheapest
Major Airline
21 Feb
9:00 pm
ONT
Ontario airport
2h 25m
DEN
12:25 am
+1
Denver Intl airport
24 Feb
10:00 pm
DEN
Denver Intl airport
2h 25m
ONT
11:25 pm
Ontario airport
$104
Frontier
09 Apr
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
13 Apr
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$108
Major Airline
21 Feb
9:00 pm
ONT
Ontario airport
2h 25m
DEN
12:25 am
+1
Denver Intl airport
23 Feb
10:00 pm
DEN
Denver Intl airport
2h 25m
ONT
11:25 pm
Ontario airport
$114
Alaska Airlines
18 Feb
9:00 pm
ONT
Ontario airport
2h 45m
SEA
11:45 pm
Seattle/Tacoma Intl airport
25 Feb
9:00 pm
SEA
Seattle/Tacoma Intl airport
2h 39m
ONT
11:39 pm
Ontario airport
$117
Major Airline
06 May
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
09 May
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$128
United Airlines
01 Mar
9:00 pm
ONT
Ontario airport
2h 15m
DEN
12:15 am
+1
Denver Intl airport
05 Mar
10:00 pm
DEN
Denver Intl airport
2h 25m
ONT
11:25 pm
Ontario airport
$137
United Airlines
01 Mar
9:00 pm
ONT
Ontario airport
2h 15m
DEN
12:15 am
+1
Denver Intl airport
05 Mar
10:00 pm
DEN
Denver Intl airport
2h 25m
ONT
11:25 pm
Ontario airport
$137
Frontier
09 Apr
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
13 Apr
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$108
Frontier
23 Apr
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
27 Apr
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$137
Major Airline
06 May
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
09 May
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$128
Frontier
01 Jun
9:00 pm
ONT
Ontario airport
2h 26m
DEN
12:26 am
+1
Denver Intl airport
04 Jun
10:00 pm
DEN
Denver Intl airport
2h 23m
ONT
11:23 pm
Ontario airport
$147
Major Airline
13 Mar
9:00 pm
ONT
Ontario airport
2h 21m
DEN
12:21 am
+1
Denver Intl airport
17 Mar
10:00 pm
DEN
Denver Intl airport
2h 28m
ONT
11:28 pm
Ontario airport
$163
Alternative routes for Ontario to United States
Compare alternative flights to and from nearby airports and cities to discover the best prices and most convenient flight times
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Flights to other cities in United States
Lost the lust for United States? Check out some flights to other cities in United States
Round-trip flights to other destinations
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*Flight prices to United States are based on prices for economy tickets found by momondo users during searches within the last 72 hours. These prices may no longer be available.