Stuttgart's automotive executives and Missouri's biotech travelers share a common problem: there's no nonstop between STL and STR, which means every business class from St. Louis to Stuttgart itinerary routes through a major East Coast or European hub. In practice, this means connecting via Chicago, Charlotte, or Atlanta domestically, then onward through Philadelphia, Frankfurt, or Munich on American, Delta, or United metal—all three carriers code-share extensively with joint venture partners, so a Delta ticket might actually put you on an Air France or KLM operated long-haul leg with fully flat seating.
Having routed this connection dozens of times, I'll say the Atlanta-to-Frankfurt-to-Stuttgart path on Delta tends to be the smoothest, since Delta One's suite (with sliding privacy doors on the 767 and A330-900 fleets) makes the transatlantic haul genuinely restful before the short Lufthansa or Delta regional hop into Stuttgart. American routes typically funnel through Philadelphia or Charlotte into Frankfurt or Munich, using their Flagship Business seats on 777s and 787s—solid, though not quite as private as Delta's suite doors. United tends to favor Newark or Chicago into Frankfurt, with Polaris seating offering direct aisle access on most widebodies serving that corridor. My insider tip: when connecting through Frankfurt, build in at least 90 minutes, since passport control for non-Schengen arrivals can bottleneck badly during the 7-9am wave of transatlantic arrivals, and missing the short Stuttgart connector means a multi-hour wait for the next flight.
January through March and again in October and November tend to offer the best value and availability in business class on this corridor, largely because Stuttgart's trade fair calendar (heavy in spring and fall) pushes demand and pricing upward outside those windows. Given the multiple connection options and shifting partner award space across American, Delta, and United, I'd strongly recommend setting up fare alerts rather than manually checking—automated tracking on this specific St. Louis to Stuttgart business class route will catch the periodic mistake fares and seasonal dips that rarely last more than 48 hours.
