Flights from Ontario to Denver (ONT to DEN)

Discover more affordable routes and cheaper dates from Ontario to Denver (ONT to DEN) within a date range.

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US$107

12:59am - 4:16am
Mon Apr 21st 2025

2h 17m
Ontario (ONT) → Denver (DEN)

Direct

Mon Apr 21st 2025 Frontier Airlines · F9 1500 Depart at 12:59am from Ontario (ONT) Fly for 2h 17m Arrive at 4:16am in Denver (DEN)
US$161

9:41pm - 3:56am
Mon Apr 21st 2025

5h 15m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 4206 Depart at 9:41pm from Ontario (ONT) Fly for 1h 14m Arrive at 10:55pm in Las Vegas (LAS)

Layover in Las Vegas for 2h 4m

Tue Apr 22nd 2025 Frontier Airlines · F9 1994 Depart at 12:59am from Las Vegas (LAS) Fly for 1h 57m Arrive at 3:56am in Denver (DEN)
US$161

2:43pm - 10:13pm
Mon Apr 21st 2025

6h 30m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 1358 Depart at 2:43pm from Ontario (ONT) Fly for 1h 10m Arrive at 3:53pm in Las Vegas (LAS)

Layover in Las Vegas for 3h 18m

Mon Apr 21st 2025 Frontier Airlines · F9 4612 Depart at 7:11pm from Las Vegas (LAS) Fly for 2h 2m Arrive at 10:13pm in Denver (DEN)
US$161

4:09pm - 11:56pm
Mon Apr 21st 2025

6h 47m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 3132 Depart at 4:09pm from Ontario (ONT) Fly for 3h 2m Arrive at 9:11pm in Houston (IAH)

Layover in Houston for 1h 6m

Mon Apr 21st 2025 Frontier Airlines · F9 4855 Depart at 10:17pm from Houston (IAH) Fly for 2h 39m Arrive at 11:56pm in Denver (DEN)
US$167

2:43pm - 12:52am
Mon Apr 21st 2025

9h 9m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 1358 Depart at 2:43pm from Ontario (ONT) Fly for 1h 10m Arrive at 3:53pm in Las Vegas (LAS)

Layover in Las Vegas for 6h 0m

Mon Apr 21st 2025 Frontier Airlines · F9 4968 Depart at 9:53pm from Las Vegas (LAS) Fly for 1h 59m Arrive at 12:52am in Denver (DEN)
US$167

10:53am - 10:13pm
Mon Apr 21st 2025

10h 20m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 2232 Depart at 10:53am from Ontario (ONT) Fly for 1h 9m Arrive at 12:02pm in Las Vegas (LAS)

Layover in Las Vegas for 7h 9m

Mon Apr 21st 2025 Frontier Airlines · F9 4612 Depart at 7:11pm from Las Vegas (LAS) Fly for 2h 2m Arrive at 10:13pm in Denver (DEN)
US$180

4:25pm - 7:49pm
Mon Apr 21st 2025

2h 24m
Ontario (ONT) → Denver (DEN)

Direct

Mon Apr 21st 2025 Frontier Airlines · F9 2908 Depart at 4:25pm from Ontario (ONT) Fly for 2h 24m Arrive at 7:49pm in Denver (DEN)
US$199

4:23pm - 7:40pm
Mon Apr 21st 2025

2h 17m
Ontario (ONT) → Denver (DEN)

Direct

Mon Apr 21st 2025 United Airlines · UA 567 Depart at 4:23pm from Ontario (ONT) Fly for 2h 17m Arrive at 7:40pm in Denver (DEN)
US$199

5:00am - 8:19am
Mon Apr 21st 2025

2h 19m
Ontario (ONT) → Denver (DEN)

Direct

Mon Apr 21st 2025 United Airlines · UA 1460 Depart at 5:00am from Ontario (ONT) Fly for 2h 19m Arrive at 8:19am in Denver (DEN)
US$255

5:44pm - 1:10am
Mon Apr 21st 2025

6h 26m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 6286 Depart at 5:44pm from Ontario (ONT) Fly for 2h 23m Arrive at 8:07pm in Portland (PDX)

Layover in Portland for 1h 28m

Mon Apr 21st 2025 Hawaiian Airlines · HA 4837 Depart at 9:35pm from Portland (PDX) Fly for 2h 35m Arrive at 1:10am in Denver (DEN)
US$256

6:55am - 11:58pm
Mon Apr 21st 2025

16h 3m
Ontario (ONT) → Denver (DEN)

2 Stops

Mon Apr 21st 2025 Hawaiian Airlines · HA 4862 Depart at 6:55am from Ontario (ONT) Fly for 2h 24m Arrive at 9:19am in Portland (PDX)

Layover in Portland for 8h 1m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6402 Depart at 5:20pm from Portland (PDX) Fly for 0h 54m Arrive at 6:14pm in Seattle (SEA)

Layover in Seattle for 2h 6m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6584 Depart at 8:20pm from Seattle (SEA) Fly for 2h 38m Arrive at 11:58pm in Denver (DEN)
US$262

5:44pm - 1:10am
Mon Apr 21st 2025

6h 26m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 2202 Depart at 5:44pm from Ontario (ONT) Fly for 2h 23m Arrive at 8:07pm in Portland (PDX)

Layover in Portland for 1h 28m

Mon Apr 21st 2025 Alaska Airlines · AS 679 Depart at 9:35pm from Portland (PDX) Fly for 2h 35m Arrive at 1:10am in Denver (DEN)
US$277

10:53am - 6:47pm
Mon Apr 21st 2025

6h 54m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Frontier Airlines · F9 2232 Depart at 10:53am from Ontario (ONT) Fly for 1h 9m Arrive at 12:02pm in Las Vegas (LAS)

Layover in Las Vegas for 3h 36m

Mon Apr 21st 2025 Frontier Airlines · F9 3540 Depart at 3:38pm from Las Vegas (LAS) Fly for 2h 9m Arrive at 6:47pm in Denver (DEN)
US$282

6:00am - 4:40pm
Mon Apr 21st 2025

9h 40m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 6288 Depart at 6:00am from Ontario (ONT) Fly for 2h 50m Arrive at 8:50am in Seattle (SEA)

Layover in Seattle for 4h 11m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6651 Depart at 1:01pm from Seattle (SEA) Fly for 2h 39m Arrive at 4:40pm in Denver (DEN)
US$289

6:00am - 4:40pm
Mon Apr 21st 2025

9h 40m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 1091 Depart at 6:00am from Ontario (ONT) Fly for 2h 50m Arrive at 8:50am in Seattle (SEA)

Layover in Seattle for 4h 11m

Mon Apr 21st 2025 Alaska Airlines · AS 620 Depart at 1:01pm from Seattle (SEA) Fly for 2h 39m Arrive at 4:40pm in Denver (DEN)
US$297

1:35pm - 4:55pm
Mon Apr 21st 2025

2h 20m
Ontario (ONT) → Denver (DEN)

Direct

Mon Apr 21st 2025 United Airlines · UA 1942 Depart at 1:35pm from Ontario (ONT) Fly for 2h 20m Arrive at 4:55pm in Denver (DEN)
US$303

6:55am - 1:53pm
Mon Apr 21st 2025

5h 58m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 4862 Depart at 6:55am from Ontario (ONT) Fly for 2h 24m Arrive at 9:19am in Portland (PDX)

Layover in Portland for 1h 2m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6337 Depart at 10:21am from Portland (PDX) Fly for 2h 32m Arrive at 1:53pm in Denver (DEN)
US$310

6:55am - 1:53pm
Mon Apr 21st 2025

5h 58m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 1058 Depart at 6:55am from Ontario (ONT) Fly for 2h 24m Arrive at 9:19am in Portland (PDX)

Layover in Portland for 1h 2m

Mon Apr 21st 2025 Alaska Airlines · AS 630 Depart at 10:21am from Portland (PDX) Fly for 2h 32m Arrive at 1:53pm in Denver (DEN)
US$321

11:33am - 7:01pm
Mon Apr 21st 2025

6h 28m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 6289 Depart at 11:33am from Ontario (ONT) Fly for 2h 49m Arrive at 2:22pm in Seattle (SEA)

Layover in Seattle for 1h 0m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6650 Depart at 3:22pm from Seattle (SEA) Fly for 2h 39m Arrive at 7:01pm in Denver (DEN)
US$329

5:44pm - 1:10am
Mon Apr 21st 2025

6h 26m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 2202 Depart at 5:44pm from Ontario (ONT) Fly for 2h 23m Arrive at 8:07pm in Portland (PDX)

Layover in Portland for 1h 28m

Mon Apr 21st 2025 Hawaiian Airlines · HA 4837 Depart at 9:35pm from Portland (PDX) Fly for 2h 35m Arrive at 1:10am in Denver (DEN)
US$329

11:33am - 7:01pm
Mon Apr 21st 2025

6h 28m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 1111 Depart at 11:33am from Ontario (ONT) Fly for 2h 49m Arrive at 2:22pm in Seattle (SEA)

Layover in Seattle for 1h 0m

Mon Apr 21st 2025 Alaska Airlines · AS 602 Depart at 3:22pm from Seattle (SEA) Fly for 2h 39m Arrive at 7:01pm in Denver (DEN)
US$330

5:44pm - 1:10am
Mon Apr 21st 2025

6h 26m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 6286 Depart at 5:44pm from Ontario (ONT) Fly for 2h 23m Arrive at 8:07pm in Portland (PDX)

Layover in Portland for 1h 28m

Mon Apr 21st 2025 Alaska Airlines · AS 679 Depart at 9:35pm from Portland (PDX) Fly for 2h 35m Arrive at 1:10am in Denver (DEN)
US$376

6:55am - 1:53pm
Mon Apr 21st 2025

5h 58m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 1058 Depart at 6:55am from Ontario (ONT) Fly for 2h 24m Arrive at 9:19am in Portland (PDX)

Layover in Portland for 1h 2m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6337 Depart at 10:21am from Portland (PDX) Fly for 2h 32m Arrive at 1:53pm in Denver (DEN)
US$377

6:55am - 1:53pm
Mon Apr 21st 2025

5h 58m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 4862 Depart at 6:55am from Ontario (ONT) Fly for 2h 24m Arrive at 9:19am in Portland (PDX)

Layover in Portland for 1h 2m

Mon Apr 21st 2025 Alaska Airlines · AS 630 Depart at 10:21am from Portland (PDX) Fly for 2h 32m Arrive at 1:53pm in Denver (DEN)
US$384

11:33am - 1:10am
Mon Apr 21st 2025

12h 37m
Ontario (ONT) → Denver (DEN)

2 Stops

Mon Apr 21st 2025 Alaska Airlines · AS 1111 Depart at 11:33am from Ontario (ONT) Fly for 2h 49m Arrive at 2:22pm in Seattle (SEA)

Layover in Seattle for 1h 13m

Mon Apr 21st 2025 Alaska Airlines · AS 2376 Depart at 3:35pm from Seattle (SEA) Fly for 0h 49m Arrive at 4:24pm in Portland (PDX)

Layover in Portland for 5h 11m

Mon Apr 21st 2025 Alaska Airlines · AS 679 Depart at 9:35pm from Portland (PDX) Fly for 2h 35m Arrive at 1:10am in Denver (DEN)
US$408

11:33am - 7:01pm
Mon Apr 21st 2025

6h 28m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Alaska Airlines · AS 1111 Depart at 11:33am from Ontario (ONT) Fly for 2h 49m Arrive at 2:22pm in Seattle (SEA)

Layover in Seattle for 1h 0m

Mon Apr 21st 2025 Hawaiian Airlines · HA 6650 Depart at 3:22pm from Seattle (SEA) Fly for 2h 39m Arrive at 7:01pm in Denver (DEN)
US$409

11:33am - 7:01pm
Mon Apr 21st 2025

6h 28m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 Hawaiian Airlines · HA 6289 Depart at 11:33am from Ontario (ONT) Fly for 2h 49m Arrive at 2:22pm in Seattle (SEA)

Layover in Seattle for 1h 0m

Mon Apr 21st 2025 Alaska Airlines · AS 602 Depart at 3:22pm from Seattle (SEA) Fly for 2h 39m Arrive at 7:01pm in Denver (DEN)
US$438

10:18am - 7:01pm
Mon Apr 21st 2025

7h 43m
Ontario (ONT) → Denver (DEN)

2 Stops

Mon Apr 21st 2025 Alaska Airlines · AS 3312 Depart at 10:18am from Ontario (ONT) Fly for 2h 27m Arrive at 12:45pm in Portland (PDX)

Layover in Portland for 0h 40m

Mon Apr 21st 2025 Alaska Airlines · AS 1008 Depart at 1:25pm from Portland (PDX) Fly for 0h 58m Arrive at 2:23pm in Seattle (SEA)

Layover in Seattle for 0h 59m

Mon Apr 21st 2025 Alaska Airlines · AS 602 Depart at 3:22pm from Seattle (SEA) Fly for 2h 39m Arrive at 7:01pm in Denver (DEN)
US$480

3:55pm - 10:44pm
Mon Apr 21st 2025

5h 49m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 4662 Depart at 3:55pm from Ontario (ONT) Fly for 1h 43m Arrive at 5:38pm in San Francisco (SFO)

Layover in San Francisco for 1h 27m

Mon Apr 21st 2025 United Airlines · UA 776 Depart at 7:05pm from San Francisco (SFO) Fly for 2h 39m Arrive at 10:44pm in Denver (DEN)
US$561

6:00am - 12:20pm
Mon Apr 21st 2025

5h 20m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 277 Depart at 6:00am from Ontario (ONT) Fly for 1h 28m Arrive at 7:28am in San Francisco (SFO)

Layover in San Francisco for 1h 7m

Mon Apr 21st 2025 United Airlines · UA 501 Depart at 8:35am from San Francisco (SFO) Fly for 2h 45m Arrive at 12:20pm in Denver (DEN)
US$561

6:00am - 2:59pm
Mon Apr 21st 2025

7h 59m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 277 Depart at 6:00am from Ontario (ONT) Fly for 1h 28m Arrive at 7:28am in San Francisco (SFO)

Layover in San Francisco for 3h 44m

Mon Apr 21st 2025 United Airlines · UA 1615 Depart at 11:12am from San Francisco (SFO) Fly for 2h 47m Arrive at 2:59pm in Denver (DEN)
US$740

7:05am - 2:59pm
Mon Apr 21st 2025

6h 54m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 5361 Depart at 7:05am from Ontario (ONT) Fly for 1h 32m Arrive at 8:37am in San Francisco (SFO)

Layover in San Francisco for 2h 35m

Mon Apr 21st 2025 United Airlines · UA 1615 Depart at 11:12am from San Francisco (SFO) Fly for 2h 47m Arrive at 2:59pm in Denver (DEN)
US$740

1:20pm - 9:34pm
Mon Apr 21st 2025

7h 14m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 5257 Depart at 1:20pm from Ontario (ONT) Fly for 1h 44m Arrive at 3:04pm in San Francisco (SFO)

Layover in San Francisco for 2h 51m

Mon Apr 21st 2025 United Airlines · UA 297 Depart at 5:55pm from San Francisco (SFO) Fly for 2h 39m Arrive at 9:34pm in Denver (DEN)
US$747

1:20pm - 8:05pm
Mon Apr 21st 2025

5h 45m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 5257 Depart at 1:20pm from Ontario (ONT) Fly for 1h 44m Arrive at 3:04pm in San Francisco (SFO)

Layover in San Francisco for 1h 21m

Mon Apr 21st 2025 United Airlines · UA 566 Depart at 4:25pm from San Francisco (SFO) Fly for 2h 40m Arrive at 8:05pm in Denver (DEN)
US$820

6:10am - 2:32pm
Mon Apr 21st 2025

7h 22m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 722 Depart at 6:10am from Ontario (ONT) Fly for 3h 3m Arrive at 11:13am in Houston (IAH)

Layover in Houston for 1h 35m

Mon Apr 21st 2025 United Airlines · UA 2473 Depart at 12:48pm from Houston (IAH) Fly for 2h 44m Arrive at 2:32pm in Denver (DEN)
US$885

7:05am - 4:40pm
Mon Apr 21st 2025

8h 35m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 5361 Depart at 7:05am from Ontario (ONT) Fly for 1h 32m Arrive at 8:37am in San Francisco (SFO)

Layover in San Francisco for 4h 18m

Mon Apr 21st 2025 United Airlines · UA 1791 Depart at 12:55pm from San Francisco (SFO) Fly for 2h 45m Arrive at 4:40pm in Denver (DEN)
US$953

6:10am - 4:35pm
Mon Apr 21st 2025

9h 25m
Ontario (ONT) → Denver (DEN)

1 Stop

Mon Apr 21st 2025 United Airlines · UA 722 Depart at 6:10am from Ontario (ONT) Fly for 3h 3m Arrive at 11:13am in Houston (IAH)

Layover in Houston for 3h 37m

Mon Apr 21st 2025 United Airlines · UA 241 Depart at 2:50pm from Houston (IAH) Fly for 2h 45m Arrive at 4:35pm in Denver (DEN)

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@sarahbb1

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@eyupitsjohn

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Roaming Sonaa

@roamingsonaa

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Andy Travels

@andy_travels

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Travel With Bender

@travelwitbender

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Wesley Mergard

@travel.with.wes

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Flights from Ontario to Denver (ONT to DEN)

Sarah Belizaire

John Ford

Roaming Sonaa

Andy Travels

Travel With Bender

Wesley Mergard

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