Originally Posted by
Toshbaf
Just fly United from San Francisco to London. British Airways in economy class is not better.
On this route regularly and I strongly disagree. First, the food on UA is beyond disgusting whereas it's adequate on BA. Second, UA has densified its planes more aggressively on the route and you are probably going to get a 777 at 10 across which is extremely uncomfortable, whereas BA flies a mix of 747s and 380s which have not (yet) been densified, so are significantly more comfortable.
The only exception is that, if you have status with UA, you get E+ which is great for leg room but doesn't address the width of the seat.
Back OT, for the OP, there are four airlines which fly SFO-LON, UA, BA, Virgin and Norwegian (which, for these purposes, is a EU airline). UA is the only US carrrier. AA codeshares with BA but you will fly on BA and DL codeshares with Virgin but you will fly on VS planes. As a no status passenger, it will be pretty miserable whichever way you look at it, but my personal opinion is that UA will be the worst - the least comfortable seat, the worst food and (often) hostile FAs.