Jersey Island is the largest of the Channel Islands off the coast of Normandy, France. There are often low fares to Jersey with British Airways, but the problem is the low fares usually require an airport transfer between London Heathrow,where most USA flights arrive and depart, to London Gatwick for the Jersey flight.
The deal available today are low fares from Oakland, California OAK with nonstop flights to London Gatwick LGW. No airport change needed.
Ticket prices drop down to $402 round trip for travel departures in mid-August to November using the AARP $65 British Airways discount for economy class tickets.
British Airways AARP $65 discount World Traveller Economy
Oakland OAK – London LGW – Jersey JER – London LGW – OAK
(This Google Flights link is Aug22-29 to allow quick searches for low fare dates, however, Aug 15 – Aug 24 shows much higher fare on Google Flights than I found on British Airways website with AARP discount.)