Find Cheap Flights from Ontario to United States

Depart
Return
1 adult
Adults
18-64
Seniors
65+
Youths
12-17
Children
2-11
Seat Infants
under 2
Lap Infants
under 2
The price shown for each flight will be the average for all passengers including any infants.
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Book cheap flights from Ontario to United States

(Round-trip)
Depart: Sat Sep 2 2017 Return: Mon Sep 4 2017 Trip spans 3 days
United
United
ONT
SFO
1h 30m
nonstop
SFO
ONT
1h 29m
nonstop
Depart: Tue Aug 22 2017 Return: Sat Aug 26 2017 Trip spans 5 days
Delta
Delta
ONT
SLC
1h 47m
nonstop
SLC
ONT
1h 47m
nonstop
Depart: Tue Oct 17 2017 Return: Tue Oct 24 2017 Trip spans 8 days
Alaska Airlines
Alaska Airlines
ONT
PDX
2h 23m
nonstop
PDX
ONT
2h 22m
nonstop
Depart: Sat Oct 7 2017 Return: Sun Oct 8 2017 Trip spans 2 days
American Airlines
American Airlines
ONT
PHX
1h 13m
nonstop
PHX
ONT
1h 15m
nonstop
Depart: Wed Oct 18 2017 Return: Sat Oct 28 2017 Trip spans 11 days
Southwest
Southwest
ONT
SEA
3h 55m
1 stop
SEA
ONT
3h 40m
nonstop
Depart: Tue Jul 18 2017 Return: Tue Jul 25 2017 Trip spans 8 days
Major Airline
Major Airline
ONT
PDX
2h 18m
nonstop
PDX
ONT
2h 15m
nonstop
Depart: Sat Oct 28 2017 Return: Mon Oct 30 2017 Trip spans 3 days
United
United
ONT
SFO
1h 23m
nonstop
SFO
ONT
1h 14m
nonstop
Depart: Sat Sep 2 2017 Return: Tue Sep 5 2017 Trip spans 4 days
Delta
Delta
ONT
SLC
1h 51m
nonstop
SLC
ONT
1h 44m
nonstop
Depart: Tue Oct 10 2017 Return: Tue Oct 17 2017 Trip spans 8 days
Delta
Delta
ONT
SLC
1h 47m
nonstop
SLC
ONT
1h 44m
nonstop
Depart: Sat Jul 1 2017 Return: Wed Jul 5 2017 Trip spans 5 days
American Airlines
American Airlines
ONT
PHX
1h 15m
nonstop
PHX
ONT
1h 11m
nonstop
Depart: Tue Aug 1 2017 Return: Thu Aug 31 2017 Trip spans 31 days
United
United
ONT
SFO
1h 30m
nonstop
SFO
ONT
1h 29m
nonstop
Depart: Thu Sep 14 2017 Return: Sun Sep 17 2017 Trip spans 4 days
Alaska Airlines
Alaska Airlines
ONT
PDX
2h 24m
nonstop
PDX
ONT
2h 20m
nonstop
Depart: Tue Jul 18 2017 Return: Sat Jul 22 2017 Trip spans 5 days
American Airlines
American Airlines
ONT
PHX
1h 15m
nonstop
PHX
ONT
1h 17m
nonstop
Depart: Thu Sep 7 2017 Return: Sun Sep 10 2017 Trip spans 4 days
United
United
ONT
SFO
1h 18m
nonstop
SFO
ONT
1h 18m
nonstop
Depart: Tue Aug 15 2017 Return: Sat Aug 26 2017 Trip spans 12 days
Alaska Airlines
Alaska Airlines
ONT
PDX
2h 18m
nonstop
PDX
ONT
2h 15m
nonstop
Depart: Thu Nov 23 2017 Return: Fri Dec 1 2017 Trip spans 9 days
Major Airline
Major Airline
ONT
PDX
4h 46m
1 stop
PDX
ONT
5h 54m
1 stop
Depart: Fri Aug 4 2017 Return: Sun Aug 6 2017 Trip spans 3 days
American Airlines
American Airlines
ONT
PHX
1h 15m
nonstop
PHX
ONT
1h 17m
nonstop
Depart: Fri Aug 18 2017 Return: Mon Aug 21 2017 Trip spans 4 days
United
United
ONT
SFO
1h 30m
nonstop
SFO
ONT
1h 29m
nonstop
Depart: Fri Aug 25 2017 Return: Sun Aug 27 2017 Trip spans 3 days
American Airlines
American Airlines
ONT
PHX
1h 13m
nonstop
PHX
ONT
1h 15m
nonstop
Depart: Wed Nov 8 2017 Return: Fri Nov 10 2017 Trip spans 3 days
United
United
ONT
SFO
1h 23m
nonstop
SFO
ONT
1h 18m
nonstop
* Prices are per person and are for e–tickets and include all taxes & fees in USD.

We attempt to get accurate prices, however, prices are not guaranteed.

Here's why:

We’re not the seller.
At KAYAK we don’t set the prices, so it’s not possible for us to guarantee what other companies are selling.

We compile tonnes of data for you
Our service lets you quickly and easily compare results from hundreds of travel sites at once. In this sense, KAYAK is a search engine and we can't guarantee prices we find.

Why aren’t prices accurate 100% of the time?
Prices on airline seats, hotel rooms and car rentals can change frequently. Several people may also be trying to buy the same travel option simultaneously. As a result, you may find, on occasion, that certain prices are no longer available.

If you have more questions or if you have a bad price to report to us,
please send us an email and someone from our team will get back to you promptly.

Airports
Origin

Ontario
$137
Destination

San Francisco
$137
Portland
$149
Seattle
$192
Phoenix
$165
Salt Lake City
$147