$559+ Cheap flights from Singapore (SIN) to Oregon
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/22. Fares are subject to change and may not be available on all flights or dates of travel.
SIN — PDX
Mar 5 — Mar 121
1 adult, Economy
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Find cheap flights from Singapore to Oregon with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Singapore to Oregon
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Last-minute
One-way
Cheapest flights from Singapore to OregonExplore the most affordable flight options available from Singapore to Oregon. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 3, 2026.
Explore the most affordable flight options available from Singapore to Oregon. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 3, 2026.
This STARLUX Airlines deal was found by Cheapflights users on 2/2. 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 STARLUX Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/232:00 pm
SIN
- BOI
2 stops22h 47m
STARLUX Airlines
Sun 9/278:24 pm
BOI
- SIN
2 stops26h 16m
STARLUX Airlines
Deal found 2/2![STARLUX Airlines logo]()
$990
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/213:20 pm
SIN
- BOI
2 stops33h 42m
EVA Air
Fri 6/129:10 pm
BOI
- SIN
2 stops24h 45m
EVA Air
Deal found 2/1![EVA Air logo]()
$1,014
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/193:45 pm
SIN
- PDX
2 stops23h 09m
Multiple Airlines
Thu 3/267:27 pm
PDX
- SIN
2 stops25h 38m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,041
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/161:15 pm
SIN
- BOI
2 stops24h 00m
Multiple Airlines
Thu 2/196:00 pm
BOI
- SIN
2 stops27h 05m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,046
This Japan Airlines deal was found by Cheapflights users on 2/1. 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 Japan Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/168:05 am
SIN
- PDX
2 stops23h 25m
Japan Airlines
Mon 4/207:05 am
PDX
- SIN
2 stops43h 40m
Japan Airlines
Deal found 2/1![Japan Airlines logo]()
$1,076
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
EVA Air
Mon 3/237:27 pm
PDX
- SIN
2 stops25h 38m
EVA Air
Deal found 2/1![EVA Air logo]()
$1,156
This Kiwi.com deal was found by Cheapflights users on 2/2. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/203:45 pm
SIN
- PDX
2 stops23h 09m
Multiple Airlines
Fri 3/277:27 pm
PDX
- SIN
1 stop31h 18m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,172
This Air Canada deal was found by Cheapflights users on 1/31. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/167:00 am
SIN
- PDX
1 stop17h 10m
Air Canada
Mon 4/207:05 pm
PDX
- SIN
2 stops28h 25m
Air Canada
Deal found 1/31![Air Canada logo]()
$1,231
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
Multiple Airlines
Mon 3/237:27 pm
PDX
- SIN
1 stop31h 18m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$1,238
This United Airlines deal was found by Cheapflights users on 2/2. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/169:00 am
SIN
- PDX
1 stop22h 33m
United Airlines
Mon 4/2012:50 pm
PDX
- SIN
2 stops26h 55m
United Airlines
Deal found 2/2![United Airlines logo]()
$1,308
This Singapore Airlines deal was found by Cheapflights users on 2/1. 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 Singapore Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/219:00 am
SIN
- BOI
1 stop40h 02m
Multiple Airlines
Fri 6/126:20 am
BOI
- SIN
1 stop21h 15m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$1,327
This United Airlines deal was found by Cheapflights users on 1/31. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/238:45 am
SIN
- BOI
1 stop20h 11m
United Airlines
Sun 9/272:11 pm
BOI
- SIN
2 stops44h 34m
United Airlines
Deal found 1/31![United Airlines logo]()
$1,612
Best flights from Singapore to OregonDiscover carefully curated flight deals from Singapore to Oregon that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 3, 2026.
Discover carefully curated flight deals from Singapore to Oregon that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 3, 2026.
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/213:20 pm
SIN
- BOI
2 stops33h 42m
EVA Air
Fri 6/129:10 pm
BOI
- SIN
2 stops24h 45m
EVA Air
Deal found 2/1![EVA Air logo]()
$1,014
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/193:45 pm
SIN
- PDX
2 stops23h 09m
Multiple Airlines
Thu 3/267:27 pm
PDX
- SIN
2 stops25h 38m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,041
This Japan Airlines deal was found by Cheapflights users on 1/31. 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 Japan Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/168:05 am
SIN
- PDX
2 stops23h 25m
Japan Airlines
Mon 4/207:05 am
PDX
- SIN
2 stops43h 40m
Japan Airlines
Deal found 1/31![Japan Airlines logo]()
$1,076
This Air Canada deal was found by Cheapflights users on 1/31. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/167:00 am
SIN
- PDX
1 stop17h 10m
Air Canada
Mon 4/207:05 pm
PDX
- SIN
2 stops28h 25m
Air Canada
Deal found 1/31![Air Canada logo]()
$1,231
This United Airlines deal was found by Cheapflights users on 2/2. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/169:00 am
SIN
- PDX
1 stop22h 33m
United Airlines
Mon 4/2012:50 pm
PDX
- SIN
2 stops26h 55m
United Airlines
Deal found 2/2![United Airlines logo]()
$1,308
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/161:15 pm
SIN
- BOI
2 stops24h 00m
Multiple Airlines
Thu 2/196:00 pm
BOI
- SIN
2 stops27h 05m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,046
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
EVA Air
Mon 3/237:27 pm
PDX
- SIN
2 stops25h 38m
EVA Air
Deal found 2/1![EVA Air logo]()
$1,156
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
Multiple Airlines
Mon 3/237:27 pm
PDX
- SIN
1 stop31h 18m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$1,238
This Expedia deal was found by Cheapflights users on 2/2. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/207:40 am
SIN
- PDX
2 stops23h 50m
Multiple Airlines
Fri 3/277:14 am
PDX
- SIN
2 stops26h 11m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,263
This United Airlines deal was found by Cheapflights users on 2/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/218:35 pm
SIN
- BOI
2 stops31h 00m
United Airlines
Fri 6/126:59 pm
BOI
- SIN
1 stop21h 16m
United Airlines
Deal found 2/1![United Airlines logo]()
$1,733
This Singapore Airlines deal was found by Cheapflights users on 2/1. 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 Singapore Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/219:00 am
SIN
- BOI
1 stop40h 02m
Multiple Airlines
Fri 6/126:20 am
BOI
- SIN
1 stop21h 15m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$1,327
This China Airlines deal was found by Cheapflights users on 2/2. 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 China Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/41:45 pm
SIN
- BOI
2 stops24h 11m
Multiple Airlines
Sun 4/58:07 am
BOI
- SIN
2 stops38h 28m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$4,309
Last-minute flights from Singapore to OregonDiscover last-minute flight deals from Singapore to Oregon. Data last updated February 3, 2026 and is based on user searches.
Discover last-minute flight deals from Singapore to Oregon. Data last updated February 3, 2026 and is based on user searches.
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/161:15 pm
SIN
- BOI
2 stops24h 00m
Multiple Airlines
Thu 2/196:00 pm
BOI
- SIN
2 stops27h 05m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,046
This EVA Air deal was found by Cheapflights users on 2/2. 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 EVA Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/193:45 pm
SIN
- PDX
2 stops23h 09m
Multiple Airlines
Thu 3/267:27 pm
PDX
- SIN
2 stops25h 38m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,041
This Gotogate deal was found by Cheapflights users on 2/2. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/198:50 am
SIN
- PDX
1 stop20h 50m
Air Canada
Thu 3/263:15 pm
PDX
- SIN
2 stops29h 00m
Air Canada
Deal found 2/2![Air Canada logo]()
$1,425
This Kiwi.com deal was found by Cheapflights users on 2/2. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/203:45 pm
SIN
- PDX
2 stops23h 09m
Multiple Airlines
Fri 3/277:27 pm
PDX
- SIN
1 stop31h 18m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$1,172
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
EVA Air
Mon 3/237:27 pm
PDX
- SIN
2 stops25h 38m
EVA Air
Deal found 2/1![EVA Air logo]()
$1,156
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/213:45 pm
SIN
- PDX
2 stops20h 53m
Multiple Airlines
Mon 3/237:27 pm
PDX
- SIN
1 stop31h 18m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$1,238
This United Airlines deal was found by Cheapflights users on 2/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/2110:20 pm
SIN
- PDX
1 stop35h 27m
United Airlines
Mon 3/235:30 am
PDX
- SIN
1 stop23h 45m
United Airlines
Deal found 2/1![United Airlines logo]()
$1,349
One-way flights from Singapore to OregonSearch for one-way flight options from Singapore to Oregon. Find affordable one-way fares based on user searches. Data last updated February 3, 2026.
Search for one-way flight options from Singapore to Oregon. Find affordable one-way fares based on user searches. Data last updated February 3, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/227:40 am
SIN
- PDX
3 stops52h 08m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$559
This China Airlines deal was found by Cheapflights users on 2/1. 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 China Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/71:45 pm
SIN
- BOI
2 stops35h 17m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$561
This SmartFares deal was found by Cheapflights users on 2/1. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/63:20 pm
SIN
- BOI
2 stops22h 38m
Multiple Airlines
Deal found 2/1![Multiple Airlines logo]()
$595
This China Airlines deal was found by Cheapflights users on 2/2. 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 China Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/11:45 pm
SIN
- PDX
2 stops38h 52m
Multiple Airlines
Deal found 2/2![Multiple Airlines logo]()
$972
This oojo deal was found by Cheapflights users on 2/1. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/17:50 pm
SIN
- PDX
1 stop29h 00m
Singapore Airlines
Deal found 2/1![Singapore Airlines logo]()
$1,260
This United Airlines deal was found by Cheapflights users on 2/2. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/18:35 pm
SIN
- PDX
3 stops36h 10m
United Airlines
Deal found 2/2![United Airlines logo]()
$2,410
Find flight deals from Singapore to Oregon
Keep the following information in mind while searching for Singapore to Oregon flight deals. Data was last updated February 3, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $1,014 (oojo) |
One-way from | $559 (Kiwi.com) |
Popular in | April |
Cheapest in | December |
Average price | $965 |
Cheapflights Fare Finder
Customize your flight search to find flights from Singapore to Oregon that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated February 3, 2026.
Use the filters below to find and compare flights from Singapore to Oregon that are best for you.
Fly from
Singapore
Fly to
Oregon
Route
Depart
Return
Price
SingaporeBoise
SIN - BOI
SINBOI
Singapore Changi
Thu 5/21
3:20 pm-11:02 am
2 stops33h 42m
Boise Air Term. Gowen Fld
Fri 6/12
9:10 pm-11:55 am
2 stops24h 45m
$1,014
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Thu 3/19
3:45 pm-11:54 pm
2 stops23h 09m
Portland
Thu 3/26
7:27 pm-12:05 pm
2 stops25h 38m
$1,041
SingaporeBoise
SIN - BOI
SINBOI
Singapore Changi
Mon 2/16
1:15 pm-10:15 pm
2 stops24h 00m
Boise Air Term. Gowen Fld
Thu 2/19
6:00 pm-12:05 pm
2 stops27h 05m
$1,046
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Thu 4/16
8:05 am-4:30 pm
2 stops23h 25m
Portland
Mon 4/20
7:05 am-5:45 pm
2 stops43h 40m
$1,076
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Sat 3/21
3:45 pm-9:38 pm
2 stops20h 53m
Portland
Mon 3/23
7:27 pm-12:05 pm
2 stops25h 38m
$1,156
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Thu 4/16
7:00 am-9:10 am
1 stop17h 10m
Portland
Mon 4/20
7:05 pm-2:30 pm
2 stops28h 25m
$1,231
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Sat 3/21
3:45 pm-9:38 pm
2 stops20h 53m
Portland
Mon 3/23
7:27 pm-5:45 pm
1 stop31h 18m
$1,238
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Fri 3/20
7:40 am-4:30 pm
2 stops23h 50m
Portland
Fri 3/27
7:14 am-12:25 am
2 stops26h 11m
$1,263
SingaporePortland
SIN - PDX
SINPDX
Singapore Changi
Thu 4/16
9:00 am-4:33 pm
1 stop22h 33m
Portland
Mon 4/20
12:50 pm-6:45 am
2 stops26h 55m
$1,308
SingaporeBoise
SIN - BOI
SINBOI
Singapore Changi
Thu 5/21
9:00 am-11:02 am
1 stop40h 02m
Boise Air Term. Gowen Fld
Fri 6/12
6:20 am-5:35 pm
1 stop21h 15m
$1,327
Showing 1-10 of 18 results
Best time to book a flight from Singapore to Oregon
Have a flexible travel schedule? Discover the best time to fly to Oregon from Singapore with our price prediction graph.
SIN-BOI
SIN-PDX
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Singapore to Oregon
SIN-USOR
SIN-BOI
SIN-PDX
What is the cheapest month to book a flight from Singapore to Oregon?
Currently, December is the cheapest month in which you can book a flight from Singapore to Oregon (average of $177). Flying from Singapore to Oregon in April is currently the most expensive (average of $1,883). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.