Delta/KLM/AirFrance are offering one of the longest running discounts in recent years with under $600 fares to Denmark, Norway and Sweden for fall 2014 travel. This deal has been around already for two months. There are few airfare deals this low going to Europe, except Norwegian Airlines, the motivation behind the discount airfare from San Francisco, Los Angeles, Florida and New York to more than a dozen airports in Scandinavia. United is in this fare war game too.
Travel was allowed through about May 15 for the outbound, but now most of the deals are for September and later into fall months.
Still, if you can fly May 6, the price is just $564 on KLM for economy round-trip from San Francisco to Stockholm via Amsterdam.
KLM SFO-ARN $564 round trip San Francisco-Stockholm May 6-13, 2014.
For fall 2014 departures, there are more options.
Air France, $567 San Francisco-Stockholm, Sweden via Paris Sep 16-23, 2014.
United Airlines has even lower fares at $510 (K fare class) in the fall for San Francisco-Stockholm route. The catch is a change of airports on the return flight arriving in Newark EWR and departing from JFK for San Francisco. That is a major commute or an opportunity to spend the night.
While Stockholm may not be your preferred destination in Europe, traveling to other cities in Europe using frequent flyer miles or paid tickets to fly from Stockholm to somewhere else may still price out several hundred dollars less than flying to your preferred airport.
Here are several articles I wrote last month about planning up to 24-hour transit stops and getting cheaper airfare to Europe by flying into Scandinavia, then flying to your desired locations with one-way or round trip tickets.
United Newark-Paris $611 round trip in spring and fall using ITA Software to find it (March 25, 2014) Tutorial on using ita matrix software.
LAX-Paris or LAX-AMS $660 United with Stockholm or Copenhagen stopover spring and fall travel (March 25, 2014). This post showed how to use the low Stockholm fare to primarily stay in Paris or Amsterdam for your European trip.
LAX to Scandinavia for $500, then hopscotch flights around Europe (March 26, 2014) This post shows how to use one-way airfare to travel around Europe with a cheap Stockholm ticket.
Thank you Norwegian. Cut $500 off airfare to Athens for TBEX Europe 14 (March 26, 2014) on getting to an expensive airfare city like Athens for less by flying to Scandinavia on a low fare.
DL/KLM SFO-Norway $571 (multiple airports) April-May 2014 (March 30, 2014)
Google Flights Map reveals the airfare deals (April 19, 2014)