Originally Posted by
Scots_Al
You can only MFU flights on BA metal, so I don't think so. FWIW I flew SFO-LAS on US a couple of years ago - it was only about £30 in Y.
You can MFU flights on IB and AA now on transatlnaitc routes.
I think if you call and book LHR-SFO-LAS//MIA-LHR it can be on the same ticket,.