American citizenship for a Brit?

I’m a British born Englishman. My Father was American born. Does this entitle me to dual nationality (British/American)?

Your Dad would have had to be an US citizen when you were born me thinks since you were not born in the USA

If your father is an American citizen, then yes.

I’m a dual American/Aussie citizen (mom is American, Dad is Aussie, and I was born in the US).

The answer depends on what year you were born, how long your father spent in the USA, and whether he was married to your mother. (I will assume so, otherwise there are additional requirements.) If he gave up his US citizenship before your birth, then you’re SOL.

Briefly, if you were born after 1986, then your US citizen father would have to have resided in the USA for at least five years (two of then after his fourteenth birthday) in order to pass on citizenship. If you were born between 1952 and 1986, that figures changes to ten years (five after his fourteenth birthday). There are other complicating wrinkles.

You can refer here.

It depends on your age.

EX.
Child born in wedlock to one U.S. citizen parent and one non U.S. citizen parent (on or after November 14, 1986)
A child born outside of the United States and in wedlock to a U.S. citizen parent and a non U.S. citizen parent, may acquire U.S. citizenship at birth if the U.S. citizen parent has been physically present in the United States or one of its outlying possessions for a period of five years, two of which were after the age of fourteen. The U.S. citizen parent must be the genetic or the gestational parent, and the legal parent of the child under local law at the time and place of the child’s birth.

IiRC you will become liable for US income taxes once you become a citizen. (Payable above a certain income threshold.)

Or to put it more technically, if you should turn out to already be a US citizen (which is what we’re talking about here), then you will have been liable for US income taxes your whole life, even if you have flown below the radar until now, and even if you have never been near the place. (There is much to be said for remaining below the radar, as those who acquired US citizenship through birth in the USA cannot.)

Even if you don’t owe anything, there is still a requirement to file–as well as FBAR requirements to report all your “overseas” savings to the IRS. This will affect non-US family members as well, and probably exclude you from most corporate financial positions (since nobody wants their company to be forced to report its finances to the USA, thanks to an American financial officer). Many routine financial arrangements will be disrupted or double-taxed.

Yeah, he’ll suddenly have a lot more taxes to pay. Not sure exactly why he wants to get US citizenship.