What actually changes
Four things have real deadlines or real money attached, and one of them catches almost everyone.
| Social Security number | On an immigrant visa, tick the Social Security box on your DS-260 and the card is mailed to your U.S. address about 7 to 10 business days after you land. No office visit. On a work visa (H-1B, L-1) you apply in person at a Social Security office after you arrive. |
| Social Security and National Insurance | The U.S. and the UK do have a social security agreement. If your employer is sending you temporarily, a certificate of coverage keeps you in one country's system instead of paying into both. If you are moving permanently, U.S. Social Security and Medicare start with your first paycheck. |
| Your UK tax year | Tell HMRC you have left. Form P85 gets your income tax right for the year you go, unless you are already filing a Self Assessment return for that year, in which case the residence pages do the same job. |
| Health cover | NHS cover ends when you stop being ordinarily resident. In the U.S., cover is usually bought through an employer and the window to enrol after you start a job is short, often about 30 days. Missing it can mean waiting months. |
| Bringing a dog | The UK is not on the CDC's high-risk list for dog rabies, so the paperwork is short: the free CDC Dog Import Form filed 2 to 10 days before travel, a microchip, and a dog that is at least six months old and healthy on arrival. Your airline will have its own rules on top. |
| Driving and credit | There is no national U.S. licence, and each state sets its own deadline once you are a resident. Your UK credit file does not cross the Atlantic either, so expect to start from zero. |
Rules here change often. Confirm current requirements at the official source before you act. (reviewed Aug 2026)
Your UK to USA timeline
- 3 months outCheck whether your employer is sending you on a certificate of coverage, and what health cover starts on day one. Get dental and optical done while you are still in the NHS system.
- 6 to 8 weeksBook shipping and start the one-year rule paperwork: an inventory of what you owned and used, which is what makes it duty free.
- 4 weeksTell HMRC (form P85 or your Self Assessment residence pages), close or convert UK accounts you will not keep, and check whether any UK account will push you over the $10,000 FBAR reporting line.
- Landing weekCustoms declaration, Social Security card, U.S. phone number and bank account. The address you give first is where the SSN card is posted.
- First 30 daysHealth insurance enrolment, driver's licence, schools if children are coming, and the state deadlines that started the day you arrived.
Kids, pets, which visa, which U.S. state, your actual move date: answer a few questions and every task above lands in a week-by-week plan you can check off and share. Free.
Common questions
Do I have to pay into both social security systems?
Usually not, if you are being sent temporarily: the U.S.-UK agreement lets a certificate of coverage keep you in one system. A permanent move means U.S. Social Security and Medicare from your first paycheck.
What happens to my NHS access?
It ends when you stop being ordinarily resident in the UK. Plan U.S. cover to start on day one, and use your employer's enrolment window, which is short.
Can I drive on my UK licence?
Briefly, in most states, with an International Driving Permit. Every state then sets its own deadline to convert once you become a resident, and there is no national rule.
What does it cost to move from the UK to the U.S.?
Sea freight, air freight and shared containers differ by multiples, and quotes for the same shipment vary widely. Three quotes six or more weeks out is worth more than any published average.