U.S. citizens who want to work in the United Kingdom must have a valid U.S. passport and a work visa from the UK. The process to obtain a work visa varies depending on the type of work you will be doing. If you do not have a valid work visa when you arrive, you might not be allowed into the country to work.

Determine Visa Qualifications

The UK offers visas to entrepreneurs, investors, skilled workers and athletes, and the requirements for each type varies. For example, entrepreneurs applying for a Tier 1 Entrepreneur visa must have £50,000 or more in investment funds; be at least 16 years old; and be able to support themselves during their stay. If you are a skilled worker applying for a Tier 2 General visa, you must speak English; hold a position that pays £20,500 per year or more; and hold a certificate of sponsorship from your employer.

Submit Visa Application

You must apply for a work visa from outside of the UK unless you are extending or changing a visa you already hold. Complete a visa application online at the Visa4UK website. During the application process, you will be prompted to make an appointment to have your photograph and fingerprints taken by the Department of Homeland Security. This information must be attached to your application and other required documentation, and mailed to UK Visas and Immigration.

Work Visa Terms

Each visa type has certain conditions and permissions that you must follow while in the UK. For example, holders of a Tier 1 Entrepreneur visa may start or run a business in the UK, work for that same business as a self-employed person and bring family members into the country. However, they may not receive public funds or work for another company in the UK. Holders of a Tier 2 General visa may work for the company that sponsored them, do volunteer work, work up to 20 hours per week in an industry with a worker shortage and study in the UK. However, they may not start working before the visa is granted or receive public funds.

Expiration and Renewal

The length of time each visa is valid for varies. For example, holders of the Tier 1 Entrepreneur visa may stay in the country for as long as three years and four months. The visa may be extended for up to two years when it expires. After five years, you may apply for a settlement visa that allows you to remain in the country indefinitely. Holders of a Tier 2 General visa may stay as long as five years and 14 days or the length of employment as indicated on the certificate of sponsorship. The visa may be be extended, but your total stay may not exceed six years.