Find cheap Delta flights to Ontario
RDU — ONT
Aug 26 — Sep 21
Round-trip
1 adult, Economy
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Cheapest Delta flights from USA to OntarioExplore the most affordable Delta flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
Explore the most affordable Delta flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:35 am
DEN
- ONT
1 stop4h 17m
Delta
Mon 8/245:05 pm
ONT
- DEN
1 stop4h 50m
Delta
Deal found 7/27![Delta logo]()
$197
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/132:37 pm
IAH
- ONT
1 stop9h 15m
Delta
Wed 8/196:00 am
ONT
- IAH
1 stop5h 37m
Delta
Deal found 7/23![Delta logo]()
$225
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/157:30 am
IAH
- ONT
1 stop6h 46m
Delta
Mon 8/1710:00 pm
ONT
- IAH
1 stop8h 37m
Delta
Deal found 7/22![Delta logo]()
$227
Best Delta flights from USA to OntarioDiscover carefully curated Delta 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 Delta 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 Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:35 am
DEN
- ONT
1 stop4h 17m
Delta
Mon 8/245:05 pm
ONT
- DEN
1 stop4h 50m
Delta
Deal found 7/23![Delta logo]()
$197
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:30 am
DEN
- ONT
1 stop4h 25m
Delta
Sat 10/106:00 am
ONT
- DEN
1 stop5h 05m
Delta
Deal found 7/23![Delta logo]()
$197
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/246:25 pm
DEN
- ONT
1 stop6h 23m
Delta
Wed 1/65:05 pm
ONT
- DEN
1 stop4h 28m
Delta
Deal found 7/26![Delta logo]()
$197
Direct Delta flights from USA to OntarioExplore non-stop Delta 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 Delta 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 Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/218:20 am
SEA
- ONT
Nonstop2h 54m
Delta
Sat 9/266:00 pm
ONT
- SEA
Nonstop2h 50m
Delta
Deal found 7/22![Delta logo]()
$247
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/107:50 pm
SEA
- ONT
Nonstop2h 50m
Delta
Sun 9/1311:54 am
ONT
- SEA
Nonstop2h 56m
Delta
Deal found 7/22![Delta logo]()
$257
This Delta deal was found by Cheapflights users on 7/24. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/102:29 pm
SEA
- ONT
Nonstop2h 50m
Delta
Mon 9/146:00 pm
ONT
- SEA
Nonstop2h 50m
Delta
Deal found 7/24![Delta logo]()
$268
Last-minute Delta flights from USA to OntarioDiscover last-minute Delta flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
Discover last-minute Delta flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:35 am
DEN
- ONT
1 stop4h 17m
Delta
Mon 8/245:05 pm
ONT
- DEN
1 stop4h 50m
Delta
Deal found 7/27![Delta logo]()
$197
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/132:37 pm
IAH
- ONT
1 stop9h 15m
Delta
Wed 8/196:00 am
ONT
- IAH
1 stop5h 37m
Delta
Deal found 7/23![Delta logo]()
$225
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/157:30 am
IAH
- ONT
1 stop6h 46m
Delta
Mon 8/1710:00 pm
ONT
- IAH
1 stop8h 37m
Delta
Deal found 7/22![Delta logo]()
$227
One-way Delta flights to OntarioSearch for one-way Delta flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
Search for one-way Delta flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/256:28 pm
DEN
- ONT
1 stop6h 06m
Delta
Deal found 7/27![Delta logo]()
$99
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/107:05 am
DEN
- ONT
1 stop6h 09m
Delta
Deal found 7/23![Delta logo]()
$104
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/197:06 pm
IAH
- ONT
1 stop6h 28m
Delta
Deal found 7/22![Delta logo]()
$113
Flights to Ontario with Delta at a glance
Find detailed information about Delta flights from USA to Ontario. Explore the options provided by Delta to plan your journey from USA to Ontario. Data last updated July 27, 2026.
Popular in | July |
|---|---|
Cheapest in | September |
Average price | $378 |
Round-trip from | $197 |
One-way from | $99 |
Good round-trip deal | $235 or less |
Good one-way deal | $238 or less |
Cheapflights Insights
Find cheap Delta flights to Ontario
US0-ONT
DEN-ONT
IAH-ONT
SEA-ONT
How long is the flight to Ontario with Delta?
On average, Delta 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.
Delta weekly flight availability to Ontario
The most flights to Ontario operated by Delta are scheduled on a Friday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (7 on average).
When is the best time to book a flight to Ontario with Delta?
The best time to book a flight to Ontario with Delta is 68 days before departure. On average, fares are higher if you book 3 days before departure.
When is the cheapest time to fly to Ontario with Delta?
Users looking for the cheapest Delta 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 Delta
Reviews of Delta
See what Cheapflights users have to say about their Delta experience.
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Delta
8,485 reviews
Overview
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7.8
Comfort
7.8
Food
7.2
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8.5
Boarding
8.1
Recent reviews
10.0
|Jul 2026Great
8.0
|Jun 2026All good with the airline
8.0
|Jun 2026Food snacks u can do better
6.0
|Jun 2026Pay for seat upgrade
8.0
|Jun 2026Pay for seat upgrades
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