Trondheim rarely appears on the radar of American business travelers, which is precisely why the routing deserves scrutiny: there's no nonstop option, and business class from Portland to Trondheim requires a connection through either Copenhagen, Frankfurt, or Amsterdam, with total journey time running close to 11.5 hours of actual flying plus layover. My preference after years of testing all three gateways is SAS through Copenhagen — their Airbus A330 and A350 business class cabins offer lie-flat seats with direct aisle access, and Copenhagen's compact layout makes for one of Europe's easiest connections, especially if you clear immigration early and head straight for the SAS lounge near the gate. Lufthansa via Frankfurt is the more corporate-heavy alternative, with their newer Allegris business seats now rolling out on select longhaul aircraft, though availability on the Frankfurt-to-Scandinavia leg is often operated by smaller regional jets without lie-flat seating, so it pays to check the aircraft type before booking. KLM through Amsterdam rounds out the trio, with Schiphol's efficient transfer process and KLM's reliable World Business Class cabin on their 787 and A330 fleet.
The final leg into Trondheim, regardless of carrier, is typically a narrowbody hop from the connecting hub, so don't expect premium cabin service to persist the whole way — treat the long-haul segment as where your comfort investment matters most. Summer is genuinely the sweet spot here: May through September not only brings Trondheim's best weather and the midnight sun phenomenon further north, but also coincides with more generous business class award space release on SAS as Scandinavian leisure demand shifts flight patterns. An insider trick I've used repeatedly: SAS often opens up saver business seats on the Copenhagen-Trondheim domestic-style connection roughly three to four weeks before departure, even when the transatlantic segment shows only standard fares, so booking the two legs separately can sometimes unlock better seat selection.
Given how thin and seasonal premium inventory is on this corridor, the smartest move is setting up continuous fare tracking rather than checking manually — automated alerts will catch the fleeting business class fare drops on this route long before they show up in a routine search.
