Salzburg's compact, single-runway airport can't handle widebody long-haul traffic, which is precisely why there's no nonstop business class from Los Angeles to Salzburg — every routing funnels through a European or East Coast hub, and the smartest connections run via Vienna, Frankfurt, or Munich. Austrian Airlines (OS) via Vienna is the natural choice for anyone chasing a true Los Angeles to Salzburg business class experience, since it keeps you on one alliance and allows for the short, scenic OS turboprop or regional jet hop into Salzburg itself. Delta, meanwhile, code-shares extensively with Austrian and offers its own Los Angeles departures using the Delta One suite on 767 or A330 aircraft, connecting through JFK or Amsterdam before a partner leg onward. United flies its Polaris business product from LAX, typically routing through Newark or Munich with a Lufthansa or United transatlantic segment feeding into a Salzburg-bound regional flight.
Having flown this corridor repeatedly, I've found the Vienna connection consistently smoother than Frankfurt or Munich during winter, when fog delays plague the German hubs more than Austria's own airport — a detail seasoned travelers rarely mention. If you're routing through Vienna on Austrian metal, request the daytime westbound Boeing 777 service when flying home, as it offers more consistent business class seating availability than the evening departures favored by leisure travelers. Munich connections via Lufthansa-United codeshares tend to run tighter on connection times, so build in at least 90 minutes there given the terminal transfer between non-Schengen arrivals and Schengen departures.
January through March and again in October and November are reliably the softest months for premium fares on this run, as ski season hasn't yet peaked and summer festival crowds have cleared out. Because pricing on this three-airline route shifts quickly with hub-specific demand swings, setting up automated fare alerts is the most reliable way to catch a favorable business class fare before it disappears.