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Get United's best fares today on flights from Ontario to Seattle from *

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Low fare calendar for flights from Ontario (ONT) to Seattle (SEA)

Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
1
2
3
4
5
6
from
$319*
Viewed:9 hours ago
Economy
Return:06/13/20
7
from
$406*
Viewed:9 hours ago
Economy
Return:06/21/20
8
from
$486*
Viewed:9 hours ago
Economy
Return:06/15/20
9
from
$319*
Viewed:9 hours ago
Economy
Return:06/16/20
10
from
$486*
Viewed:9 hours ago
Economy
Return:06/17/20
11
from
$403*
Viewed:9 hours ago
Economy
Return:06/25/20
12
No available fares
13
from
$327*
Viewed:9 hours ago
Economy
Return:06/20/20
14
from
$396*
Viewed:9 hours ago
Economy
Return:06/21/20
15
from
$474*
Viewed:9 hours ago
Economy
Return:06/29/20
16
from
$336*
Viewed:9 hours ago
Economy
Return:06/23/20
17
from
$551*
Viewed:9 hours ago
Economy
Return:07/01/20
18
from
$452*
Viewed:9 hours ago
Economy
Return:06/25/20
19
No available fares
20
from
$408*
Viewed:9 hours ago
Economy
Return:07/04/20
21
from
$420*
Viewed:9 hours ago
Economy
Return:06/28/20
22
from
$344*
Viewed:9 hours ago
Economy
Return:07/06/20
23
from
$390*
Viewed:9 hours ago
Economy
Return:07/07/20
24
from
$270*
Viewed:9 hours ago
Economy
Return:07/08/20
25
from
$266*
Viewed:9 hours ago
Economy
Return:07/09/20
26
No available fares
27
from
$254*
Viewed:9 hours ago
Economy
Return:07/11/20
28
from
$314*
Viewed:9 hours ago
Economy
Return:07/12/20
29
from
$259*
Viewed:9 hours ago
Economy
Return:07/13/20
30
from
$406*
Viewed:9 hours ago
Economy
Return:07/14/20
from
$406*
Viewed:9 hours ago
Economy
Return:07/15/20
from
$254*
Viewed:9 hours ago
Economy
Return:07/18/20
Lowest PriceToday
*Prices have been available for round trips within the last 48 hours and may not be currently available. Fares listed may be Basic Economy, which is our most restrictive fare option and subject to additional restrictions. Additional baggage charges and fees for other optional service may apply. Other terms and conditions may apply.

Looking for additional flights from Ontario to Seattle?

FromToDatesFare TypePrice

Ontario (ONT)

Seattle (SEA)

Depart: 07/07/20

Return: 07/21/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/14/20

Return: 07/28/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/15/20

Return: 07/29/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/18/20

Return: 08/01/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/21/20

Return: 08/04/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/22/20

Return: 08/05/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/25/20

Return: 08/08/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/28/20

Return: 08/11/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 07/29/20

Return: 08/12/20

Roundtrip
from
$166*
Viewed:8hoursago

Ontario (ONT)

Seattle (SEA)

Depart: 08/01/20

Return: 08/15/20

Roundtrip
from
$166*
Viewed:8hoursago

*Prices have been available for round trips within the last 48 hours and may not be currently available. Fares listed may be Basic Economy, which is our most restrictive fare option and subject to additional restrictions. Additional baggage charges and fees for other optional service may apply. Other terms and conditions may apply.

Weather in Seattle

Friday light rain
62°F 06/05/20
Saturday moderate rain
60°F 06/06/20
Sunday moderate rain
60°F 06/07/20
Monday light rain
61°F 06/08/20
Tuesday moderate rain
50°F 06/09/20
Wednesday scattered clouds
76°F 06/10/20
Thursday overcast clouds
72°F 06/11/20
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