Valencia remains one of the more gratifying puzzles in transatlantic routing, precisely because there's no nonstop answer to solve. Business class from Austin to Valencia always involves a connection, and the most reliable path runs through Heathrow via American Airlines' transatlantic joint venture with British Airways and Iberia — book AUS-LHR on American metal or codeshare, then let BA or Iberia carry you the final leg into VLC. The factual baseline worth remembering: this routing takes roughly 10 hours of total flight time, and American, British Airways, and Iberia all participate in the joint venture that makes award and revenue connections here relatively seamless. A second, often overlooked option is connecting through Madrid on Iberia, whose A330 business class cabin and lie-flat seats make for a gentle final hop into VLC that feels more like a shuttle than a redeye.
I've flown this itinerary enough times to have opinions about the long-haul segment, which is where you should spend your effort choosing equipment. American's 787 business class, with its Cathay-style staggered pods, is a reasonable option out of DFW if you're repositioning from Austin, but the real prize is snagging British Airways' Club Suite — found on their newer 777 and A350 aircraft — which offers a proper door and more privacy than BA's older Club World cabins. If given a choice at booking, always check the specific aircraft variant on the AUS/DFW-LHR or IAH-LHR sector, since older 777s still fly the outdated forward-facing Club World seat.
Heathrow's T3 to T5 transfer (if you land on American and connect to BA) requires a security recheck, so budget at least two hours if your connection routes through there. April, May, September, and October are the sweet spots for this trip — shoulder season in Valencia means warm days, thinner crowds at the Ciudad de las Artes, and softer fares before summer's peak. Given how frequently award space and pricing shift across three carriers and two possible hub cities, setting up fare alerts for this route is the smartest way to catch the right combination before it disappears.