There's a peculiar satisfaction in routing through legacy European hubs to reach a place as compact and dramatic as Montenegro's coastline, and after logging more miles than I care to admit on this itinerary, I can say definitively: there is no nonstop option for business class from Washington Reagan to Podgorica, which means your journey runs through Frankfurt, Munich, or Istanbul depending on carrier. Delta partners with its transatlantic joint venture to funnel passengers through Amsterdam or via codeshare into Lufthansa's network, while Lufthansa itself offers direct access through Frankfurt or Munich, and Turkish Airlines routes everyone through Istanbul. Given that DCA doesn't handle every widebody type, expect your outbound long-haul segment to depart from a larger East Coast gateway on select itineraries, so double-check your ticketed connection before booking ground transport.
My strong preference on this routing is Lufthansa, particularly if you can secure their new Allegris business class, which features suites with closing doors on select 787 and A350 aircraft — a meaningful upgrade over the older long-haul business seat still flying on many Frankfurt routes. Turkish Airlines is the wildcard worth considering: their business class includes a dedicated lounge experience in Istanbul that rivals any in Europe, complete with a putting green and live cooking stations, making a longer layover almost desirable rather than a chore. If you connect through Munich on Lufthansa, arrive early enough to enjoy their satellite terminal lounge rather than rushing — Montenegro-bound connections are often on smaller regional aircraft with limited business cabins, so reconfirm your seat assignment 48 hours out, as downgrades happen more often on this leg than travelers expect.
Winter and shoulder-season months — January through March, then October and November — consistently offer the softest fares, since Adriatic coastal tourism collapses outside summer, pulling premium demand down with it. Given the multiple viable routings and volatile award space through these hub cities, setting up fare alerts is genuinely the smartest way to catch a Washington Reagan to Podgorica business class fare before it disappears.