Find cheap Southwest flights to Ontario
RDU — ONT
Aug 26 — Sep 21
Round-trip
1 adult, Economy
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Cheapest Southwest flights from USA to OntarioExplore the most affordable Southwest flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
Explore the most affordable Southwest flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:10 am
SFO
- ONT
1 stop6h 15m
Southwest
Mon 8/245:15 am
ONT
- SFO
1 stop4h 55m
Southwest
Deal found 7/27![Southwest logo]()
$151
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:10 am
SFO
- ONT
1 stop4h 45m
Southwest
Thu 8/275:45 pm
ONT
- SFO
1 stop5h 40m
Southwest
Deal found 7/22![Southwest logo]()
$157
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/209:05 am
DEN
- ONT
Nonstop2h 15m
Southwest
Mon 8/248:10 am
ONT
- DEN
Nonstop2h 10m
Southwest
Deal found 7/25![Southwest logo]()
$157
Best Southwest flights from USA to OntarioDiscover carefully curated Southwest flight deals from USA to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
Discover carefully curated Southwest flight deals from USA to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/275:10 am
SFO
- ONT
1 stop6h 15m
Southwest
Mon 8/315:45 pm
ONT
- SFO
1 stop5h 40m
Southwest
Deal found 7/26![Southwest logo]()
$151
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/296:10 am
SFO
- ONT
1 stop5h 05m
Southwest
Mon 8/315:40 am
ONT
- SFO
1 stop3h 40m
Southwest
Deal found 7/26![Southwest logo]()
$151
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/156:10 am
SFO
- ONT
1 stop9h 05m
Southwest
Sat 8/222:55 pm
ONT
- SFO
1 stop3h 25m
Southwest
Deal found 7/25![Southwest logo]()
$156
Direct Southwest flights from USA to OntarioExplore non-stop Southwest flight options from USA to Ontario based on user searches, and compare prices and availability for your desired travel dates. Data last updated July 27, 2026.
Explore non-stop Southwest flight options from USA to Ontario based on user searches, and compare prices and availability for your desired travel dates. Data last updated July 27, 2026.
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/209:05 am
DEN
- ONT
Nonstop2h 15m
Southwest
Mon 8/248:10 am
ONT
- DEN
Nonstop2h 10m
Southwest
Deal found 7/25![Southwest logo]()
$157
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/198:50 pm
HOU
- ONT
Nonstop3h 15m
Southwest
Wed 8/2612:30 pm
ONT
- HOU
Nonstop3h 05m
Southwest
Deal found 7/22![Southwest logo]()
$205
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/248:05 am
HOU
- ONT
Nonstop3h 10m
Southwest
Mon 9/2811:00 am
ONT
- HOU
Nonstop3h 05m
Southwest
Deal found 7/23![Southwest logo]()
$220
Last-minute Southwest flights from USA to OntarioDiscover last-minute Southwest flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
Discover last-minute Southwest flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:10 am
SFO
- ONT
1 stop6h 15m
Southwest
Mon 8/245:15 am
ONT
- SFO
1 stop4h 55m
Southwest
Deal found 7/27![Southwest logo]()
$151
This Southwest deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:10 am
SFO
- ONT
1 stop4h 45m
Southwest
Thu 8/275:45 pm
ONT
- SFO
1 stop5h 40m
Southwest
Deal found 7/22![Southwest logo]()
$157
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/209:05 am
DEN
- ONT
Nonstop2h 15m
Southwest
Mon 8/248:10 am
ONT
- DEN
Nonstop2h 10m
Southwest
Deal found 7/25![Southwest logo]()
$157
One-way Southwest flights to OntarioSearch for one-way Southwest flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
Search for one-way Southwest flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/245:10 am
SFO
- ONT
1 stop4h 45m
Southwest
Deal found 7/26![Southwest logo]()
$76
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/192:35 pm
SFO
- ONT
1 stop6h 20m
Southwest
Deal found 7/23![Southwest logo]()
$79
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/156:10 am
SFO
- ONT
1 stop9h 05m
Southwest
Deal found 7/25![Southwest logo]()
$81
Flights to Ontario with Southwest at a glance
Find detailed information about Southwest flights from USA to Ontario. Explore the options provided by Southwest to plan your journey from USA to Ontario. Data last updated July 27, 2026.
Cheapflights Insights
Find cheap Southwest flights to Ontario
US0-ONT
SFO-ONT
DEN-ONT
HOU-ONT
How long is the flight to Ontario with Southwest?
On average, Southwest flights from the United States to Ontario take 3 hours 20 minutes. Flights to Ontario from other popular cities in the United States will vary in length. Below are a few examples of popular routes and their flight times.
Southwest weekly flight availability to Ontario
The most flights to Ontario operated by Southwest are scheduled on a Monday (36 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (24 on average).
When is the best time to book a flight to Ontario with Southwest?
The best time to book a flight to Ontario with Southwest is 77 days before departure. On average, fares are higher if you book 2 days before departure.
When is the cheapest time to fly to Ontario with Southwest?
Users looking for the cheapest Southwest fares to Ontario should consider flying on Saturday at noon, when prices are typically cheapest. Budget-minded travellers will want to avoid Sunday afternoons, when prices are usually at their highest.
FAQs about flights to Ontario with Southwest
Reviews of Southwest
See what Cheapflights users have to say about their Southwest experience.
Overview
Reviews
Southwest
4,229 reviews
Overview
Food
7.0
Entertainment
7.5
Comfort
8.0
Crew
8.6
Boarding
8.1
Recent reviews
10.0
|Jul 2026Good
8.0
|Jun 2026One delay in a 2 layover flight=a good trip. The crew was great.
6.0
|Jun 2026The seats were super cramped and couldn’t move without hitting other passengers
8.0
|Jun 2026The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
10.0
|Jun 2026On time and no problems
1 out of 1410
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