American citizens traveling to Scotland, England, Wales, or Northern Ireland do not require a visa but will need a valid passport.

Whether you need a passport for Scotland depends entirely on your nationality and where you are traveling from. If you are a British citizen traveling from England, Wales, or Northern Ireland, you do not need a passport to enter Scotland, as you are staying within the United Kingdom; however, most domestic airlines (like British Airways or EasyJet) will still require a "valid photo ID" such as a driving license to board the plane. If you are an Irish citizen traveling from the Republic of Ireland, you can enter Scotland without a passport under the "Common Travel Area" agreement, though you still need some form of acceptable photo ID for airline travel. For everyone else, including citizens of the EU, USA, Canada, and Australia, a valid passport is mandatory for entry into the UK (including Scotland). Since Brexit, EU national ID cards are no longer accepted for most travelers entering the UK, making a physical passport an essential requirement for international visitors wishing to explore the Highlands or the streets of Edinburgh.