What state is the most easterly point in the US?

Alaska. Semisopochnoi Island, in the Aleutian chain of islands, is at 179 degrees 46 minutes east longitude, which is about as "east" as it can get.

If we restrict ourselves to the Continental United States, then the West Quoddy Head Lighthouse near Luboc, Maine, is the easternmost point.

(Pop Culture Note: West Quoddy Head Lighthouse was the fictional setting of the Walt Disney movie "Pete's Dragon". You may remember the song about "Passamaquoddy, Maine".)
Alaska. Semisopochnoi Island, in the Aleutian chain of islands, is at 179 degrees 46 minutes east longitude, which is about as "east" as it can get.

If we restrict ourselves to the Continental United States, then the West Quoddy Head Lighthouse near Luboc, Maine, is the easternmost point.

(Pop Culture Note: West Quoddy Head Lighthouse was the fictional setting of the Walt Disney movie "Pete's Dragon". You may remember the song about "Passamaquoddy, Maine".)