Airlines with flights from Ontario to Seattle

There are 6 airlines with scheduled flights between ONT and SEA. Delta, Alaska Airlines and Frontier has non-stop flights from Ontario International Airport to Seattle Airport and the flight time is 3 hours.

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Direct

$Delta Air Lines from {( $airportFrom->city_name }} to Seattle$

Non-stop

3h 0min

Direct

$Alaska Airlines from {( $airportFrom->city_name }} to Seattle$

Non-stop

2h 41min

Direct

$Frontier Airlines from {( $airportFrom->city_name }} to Seattle$

Non-stop

2h 55min

Via Sacramento

4h 5min

Via San Jose

4h 5min

Via Portland

4h 10min

Via Oakland

4h 10min

Via San Francisco

4h 23min

NEW

Via Santa Rosa

4h 36min

Via Las Vegas

4h 40min

Via Salt Lake City

4h 44min

NEW

Via Boise

4h 54min

Via Phoenix

4h 55min

NEW

Via Salt Lake City

5h 16min

Via Phoenix

5h 25min

Via Las Vegas

6h 51min

Schedules

Non-stop with Delta Air Lines

Total flight time: 3 hours
Sky Team Alliance
Seattle is a Delta Air Lines hub.

40 flights per week
Embraer 175 (Enhanced Winglets)
First class available

ONT

Direct

SEA

Flight

Mon

Jun 15

Tue

Jun 16

Wed

Jun 17

Thu

Jun 18

Fri

Jun 19

Sat

Jun 20

Sun

Jun 21

DL3816

06:20

DL4070

11:57

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12:02

DL4031

17:59

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The timetable & schedule information was updated at 2026-04-21

Non-stop with Alaska Airlines

Total flight time: 2 hours and 41 minutes
One World Alliance
Seattle is a Alaska Airlines hub (Primary hub).

27 flights per week
Boeing 737MAX 9 Passenger

Boeing 737MAX 8 Passenger

Boeing 737-900 (winglets) Passenger/BBJ3

Boeing 737-800 (winglets) Passenger/BBJ2

Boeing 737-700 Passenger
Business and first class available

ONT

Direct

SEA

Flight

Mon

Jun 15

Tue

Jun 16

Wed

Jun 17

Thu

Jun 18

Fri

Jun 19

Sat

Jun 20

Sun

Jun 21

AS607

06:02

AS654

12:04

12:08

AS567

14:05

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14:05

AS575

17:26

17:54

17:26

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17:26

AS594

21:20

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21:20

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The timetable & schedule information was updated at 2026-04-21

Non-stop with Frontier Airlines

Total flight time: 2 hours and 55 minutes
Low-cost airline

12 flights per week
Airbus A321neo

ONT

Direct

SEA

Flight

Mon

Jun 15

Tue

Jun 16

Wed

Jun 17

Thu

Jun 18

Fri

Jun 19

Sat

Jun 20

Sun

Jun 21

F92275

16:03

10:02

16:03

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The timetable & schedule information was updated at 2026-04-21

Via Sacramento with Southwest Airlines

Total flight time: 4h 05m - 6h 20m.
Low-cost airline

62 flights per week

ONT

Via SMF

SEA

Flight

Mon

Jun 15

Tue

Jun 16

Wed

Jun 17

Thu

Jun 18

Fri

Jun 19

Sat

Jun 20

Sun

Jun 21

WN3166
WN1166

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