Source: https://help.archive.org/help/how-do-i-make-a-wire-transfer/
SCT is not contingent on EU or Euro participation - SEPA membership is distinct from those. That is how Iceland, Norway and Switzerland can reap the benefits (the latter not even EEA member, though effective treaties are now somewhat similar). As long as an US bank has a correspondent branch/account/partnership/whatever inside SEPA, they can make it almost free to receive money via SEPA, and then possibly still save on currency conversion and transaction cost as they clear in bulk across the pond.
HOWEVER it's conceivable that the USA bank might end up charging some BS fees on their side just because they can. That's hard to control for.
You clipped it, but it's GB74RBOS... and the RBOS stands for Royal Bank Of Scotland.
https://en.wikipedia.org/wiki/Single_Euro_Payments_Area#Cove...