It’s generally more expensive to depart on a Tuesday, if you have to leave on this day you can still search on Cheapflights to find great options that meet your needs.
The best pricing can be found in the month of October. Prices to Oslo from Portland average $859. You can even find prices in October for less than $859, as users have found deals to Oslo from as low as $506. The month of March appears to be one of the more expensive times to travel to Oslo from Portland. Flying in the targeted month can save you up to 40%.
Unlike in the evening, when flights are generally more expensive, you can save up to 16% on flights from Portland to Oslo by exploring options for tickets in the afternoon.