Routes out of Seattle-Tacoma airport (SEA) served by Boeing 747 [duplicate]

I checked this by paging through the FlightAware results, then looking at all the international routes from SEA and verifying the ones operated with 747s, excluding cargo flights (Korean Air Lines and China Airlines both look like they have 747 service from Seattle, but they're freighters) and one-offs.

And Seattle to Frankfurt on Lufthansa 491 is the only regularly scheduled route I found. That flight usually uses 747-8 aircraft, and there's no plan to decommission those anytime soon, though Lufthansa could assign different aircraft to the route at any time.

Seattle isn't a particularly huge market, nor is it a major hub, so most airlines use smaller aircraft there. You'd have more options with a connecting flight, such as through SFO or LAX.