Visa for England?

Not sure how Brexit (which hasn't happened yet) comes into it, but what is your nationality?

Absolute not. And even if Brexit succeeds, you will not need a visa if US citizen.

Well, first, Brexit has not occurred, I think the latest word is October, maybe. maybe not, maybe later, it seems to be one of the great unknowns.

Second, the United Kingdom (England, Scotland, Wales, and Northern Ireland) have always handled their own immigration, not being part of the Schengen agreement; so it is unlikely that for non-EU visitors they would suddenly change requirements.

Bottom line, as always, a visit from a US Citizen needs no Visa obtained ahead of time for a tourist visit up to six months. There is no guarantee that they will allow six months, it is up to the immigration agent when you land, but that is the general result.

Without knowing your nationality we can only give some examples of countries that have no visa requirement for a limited visit. Brexit is not a factor. You might find more (official) information here: https://www.justlanded.com/english/United-Kingdom/UK-Guide/Visas-Permits/Visas-for-the-United-Kingdom

Thank you! I am a U.S. citizen.

Brexit will have no effect on people who already live outside the European Union. The UK is actually making it easier to visit by eliminating landing cards and allowing US citizens to use the e-passport gates eventually.