- They fly out of Oakland airport, OAK, not San Francisco Airport.
- They don't fly non-stop to Oslo, apparently. Itineraries to Oslo from OAK connect in London, Gatwick.
- OAK<->LGW September 18th - 24th indeed $499
- OAK<->LGW July 3rd - 10th $1,189. So you'll still want to buy tickets well in advance.
There is a non-stop flight, Norwegian Air Shuttle 7064. You can look at its flight path here: https://flightaware.com/live/flight/NAX7064
The flight leaving tomorrow was $340 one way when I checked now. Round-trip, I was able to find a non-stop OAK--OSL ticket for $510 (similar September dates to yours).
There used to be OAK <-> OSL non-stop until last October but I guess there is not enough people to keep it sustainable.
Some of the fare prices to Europe are very cheap, but not always.
- They fly out of Oakland airport, OAK, not San Francisco Airport.
- They don't fly non-stop to Oslo, apparently. Itineraries to Oslo from OAK connect in London, Gatwick.
- OAK<->LGW September 18th - 24th indeed $499
- OAK<->LGW July 3rd - 10th $1,189. So you'll still want to buy tickets well in advance.