The deals to Europe keep coming. Today there are all kinds of low fares to many cities across Europe. San Francisco to London is priced in the $400s with all three alliances through online travel agencies. Google Flights shows low fares around $500 for Star Alliance and using those dates to search Momondo.com finds ticket prices with all three alliances from $437 to $488.
Google Flights San Francisco SFO – London LHR
Momondo.com San Francisco SFO – London LHR
$440 United and $470 British Airways May 4-14