Your passport should be valid for the proposed duration of your stay. You don’t need any additional period of validity on your passport beyond this.
US immigration officials will accept British passports extended by 12 months by British Embassies and Consulates under exceptional measures put in place in mid-2014, but you will need to apply for a visa from the nearest US Embassy or Consulate before travelling.
Visa Waiver Programme (VWP)
The VWP allows most British Citizen passport holders to visit the US for up to 90 days. The types of journey permissible under the VWP include tourism, certain types of business visit and transit to another country. If you have a British passport that describes your nationality as something other than ‘British Citizen’, or if your passport has been extended by 12 months under exceptional measure put in place in mid 2014, you don’t qualify for entry to the US under the VWP and you’ll need to apply for a visa from the nearest US Embassy or Consulate.
Travel under the VWP is restricted to travellers with passports that include certain security features. If you have doubts about whether you’re eligible to enter the US under the VWP (eg if you have a criminal record or have been arrested even if it didn’t result in a conviction), or about visa matters generally, contact the nearest US Embassy or Consulate for advice.
Those travelling under the VWP arriving by air or sea should provide details online at least 72 hours before travel. This is known as an Electronic System for Travel Authorisation or ESTA. If you do not have an ESTA you’ll be refused travel to the USA. If you’re arriving by land, you do not need to complete an ESTA before you arrive at the border. Getting an ESTA is a separate process to providing your airline with advance passenger information (details of your passport, country of residence, address of your first night’s accommodation in the US etc). For more information, and to apply online, visit the official ESTA website.
The VWP is intended to be used for occasional, short visits to the US. If a US immigration officer thinks you’re trying to ‘reset’ the clock by making a short trip out of the US and re-entering for another 90-day period, you can be denied entry. If you travel from the US to Canada, Mexico and the Caribbean you can usually re-enter using the ESTA and admission stamp you were issued when you first arrived in the US, although the time you spend outside of the country is included in the 90 days allotted for your visit. Make sure you’re clear about the length of time the immigration officer has authorised you to remain in the US if you re-enter under the same ESTA.
When you arrive in the USA you will need to be able to show that you have enough funds available to support yourself during your stay, even if you’re staying with family and friends. Further details on the VWP and other aspects of US immigration rules are available from the Customs and Border Protection website.
UK Emergency Travel Documents
UK Emergency Travel Documents (ETD) aren’t valid for entry into the United States under the VWP. If you’re planning to enter the US using an ETD you must apply for a visa from the nearest US Embassy or Consulate before you travel.
Bringing medicines into the US
There are restrictions and prohibitions on the import of certain prescription drugs into the US. The US Department for Homeland Security website contains further information and advice on bringing pharmaceuticals and controlled substances into the US.
Travelling with children
If a child (under the age of 18) is travelling with only one parent or someone who isn’t a parent or legal guardian, you may be asked to provide certain documents at the border. For further information, see the US Customs and Border Protection website.