How long is an American allowed to stay in the UK just on a passport?

Question

Also, what is the penalty if the duration of the visit lasts longer than allowed? Is there a ban from re-entering the UK?

Answer 1

yes i agree it is too long given the way they treat us. they can stay for 6 months ( us 3 ) don't need a return ticket or to declare the address they will stay at on the first night as we do. don't get fingerprinted of photographed like us. time we changed a few things in the UK and did to others as they do to us.

Answer 2

Too long!