California travel guide

Travel Advice

Before you travel

No travel can be guaranteed safe. Read all the advice in this guide. You may also find it helpful to: 

• see general advice for women travellers
• read our guide on disability and travel abroad
• see general advice for LGBT+ travellers
• read about safety for solo and independent travel
• see advice on volunteering and adventure travel abroad

Travel insurance

If you choose to travel, research your destinations and get appropriate travel insurance. Insurance should cover your itinerary, planned activities and expenses in an emergency.

About FCDO travel advice

The Foreign, Commonwealth & Development Office (FCDO) provides advice about risks of travel to help you make informed decisions. Find out more about FCDO travel advice.

Get travel advice updates 

Sign up to get email notifications when this travel advice is updated.  

Follow FCDO:    

• travel advice on X 

• travel advice on Facebook 

• Travel Aware on Instagram

This information is for people travelling on a full ‘British citizen’ passport from the UK. It is based on the UK government’s understanding of the current rules for the most common types of travel. 

You should comply with all entry, visa and other conditions of entry. The authorities in the US set and enforce entry rules strictly. You may be liable to arrest or detention if you break the rules. If you’re not sure how these requirements apply to you, contact the US Embassy or a consulate in the UK.

Passport validity requirements

To enter the US, your passport must be valid for the length of your planned stay.

If you’re travelling through another country on your way to or from the US, check the entry requirements for that country. Many countries will only allow entry if you have at least 6 months validity remaining on your passport. 

Dual nationals  

US law requires US citizens to enter and exit the US using a US passport. Contact the US Embassy or a consulate in the UK for more information.

Visa requirements

To enter or transit through the US, you must have either an Electronic System for Travel Authorisation (ESTA) or a visa.

The US State Department has more information on visas.

Applying for an ESTA

ESTA is an automated system that determines the eligibility of visitors to travel to the US under the Visa Waiver Program (VWP). You can apply for an ESTA via the Official ESTA Application Website or using the ESTA Mobile app on android or on iOS.

All Visa Waiver Program (VWP) travellers intending to enter the US by land, sea and air will be required to obtain an approved ESTA prior to application for admission at land border ports of entry. Individuals who are not eligible to travel under the VWP may apply for a visa at any U.S. Embassy & Consulates.

You may not be able to apply for an ESTA visa waiver if you have:

• been arrested (even if the arrest did not result in a criminal conviction)
• a criminal record
• been refused admission into, or have been deported from, the US
• previously overstayed under an ESTA visa waiver

Information on whether you are eligible for an ESTA visa waiver can be found in the help section of the official ESTA Application Website.

You cannot normally apply for an ESTA visa waiver if you were in the following countries on or after March 2011: 

• Iran
• Iraq
• Libya
• North Korea
• Somalia
• Sudan
• Syria
• Yemen

You cannot apply for an ESTA visa waiver if you travelled to or were in Cuba on or after 12 January 2021. 

If you are not eligible for an ESTA, you must instead apply for a US visa.

Applying for a visa

The US Embassy in London has information on how to apply for a visa.

US visa appointments

Visa appointments at the US Embassy in London are limited. Plan your application as far ahead as possible before travel. If you need to travel urgently, you can request an expedited interview through the US Embassy’s appointment service provider.

The US Embassy has more information on visa appointments.

Children and young people

Anyone aged 17 and under must:

• have a valid visa or ESTA on arrival
• be able to provide evidence about the purpose, location and length of their visit if asked by immigration officials
• have a letter of consent, preferably in English and notarised from one or both parents if travelling alone, with only one parent, or with someone who is not a parent or legal guardian

The US authorities can stop you entering the country if they have safeguarding concerns about a child. If this happens, the US authorities will take the child into their care, and their return from the US could take months. The FCDO cannot speed up the return of British nationals aged 17 and under from the US.

The US government has information about children travelling to the US. If you have questions, contact the US Embassy in the UK.

Vaccine requirements

For details about medical entry requirements and recommended vaccinations, see TravelHealthPro’s US guide.

Customs rules 

There are strict rules about goods you can take into or out of the US. You must declare anything that may be prohibited or subject to tax or duty.

Global Entry

The US Customs and Border Protection Trusted Traveller Program (TTP) Global Entry allows pre-approved, low-risk travellers expedited clearance at some US airports. If you’re a British citizen, you can register to get a UK background check. If you pass the background checks, you’ll be invited to apply for Global Entry for UK Citizens.

Terrorism

There is a high threat of terrorist attack globally affecting UK interests and British nationals, including from groups and individuals who view the UK and British nationals as targets. Stay aware of your surroundings at all times.   

UK Counter Terrorism Policing has information and advice on staying safe abroad and what to do in the event of a terrorist attack. Find out how to reduce your risk from terrorism while abroad.

Terrorism in the USA

Attacks could be indiscriminate, including in places visited by foreigners. You should remain aware of your surroundings, keep up to date with local media reports and follow the advice of local authorities. Targets could include:

• crowded areas
• transportation networks
• public events

The US Department of Homeland Security provides current alerts within the US and its territories.

Crime

Protecting your belongings

Do not leave passports in rental cars, especially not in the boot. Gangs may target vehicles driven by people who look like tourists.

Violent crime

Violent crime and gun crime rarely affect tourists, but take care in unfamiliar areas. Try not to walk through quieter areas alone, especially at night. You can find public advisories and information about recent incidents on local law enforcement websites.

Mass shooting incidents can happen but are a very small percentage of murders. The US Department of Homeland Security has advice on what to do in an active shooter incident.

Research your destination before you travel and follow the advice of local authorities. Crime linked to illegal drugs is a major issue in Mexican states bordering Arizona, California, New Mexico and Texas. Some foreign nationals have been victims of crime in the border regions, but there is no evidence they were targeted because of their nationality.

Protests

Protests are common and can become violent. Follow the instructions of local authorities who may introduce curfews or emergency orders. If you attend peaceful protests:

• be mindful of your surroundings
• move away if there are signs of trouble
• follow the instructions of local authorities

Laws and cultural differences

US states may have different laws. While you are in a state, you are subject to both that state’s laws as well as national (federal) law.

Personal ID

Always carry a passport showing you have permission to enter or remain in the US.

Alcohol laws

The national legal age for buying and drinking alcohol is 21. Some states have different laws. If you are aged 20 or under, check state laws before drinking or buying alcohol.

Illegal drugs and prison sentences

Possession or trafficking of illegal drugs in the US can carry a long prison sentence and a fine. Check state laws to make sure you follow laws on possession and use of controlled substances. The US Department of Justice provides a list of all controlled substances.

LGBT+ travellers

The US is a very diverse society and attitudes towards LGBT+ people differ hugely across the country. You can find more detail on LGBT+ issues in the US on the Human Rights Campaign website.

Read more advice for LGBT+ travellers. 

Transport risks

Road travel

If you are planning to drive in the US, see information on driving abroad and check the driving rules in the states you’ll be visiting.

You can use a UK photocard driving licence to drive in the US. You may need to get the 1949 version of the international driving permit (IDP) as well. IDP requirements vary in each state. For more information, consult individual states’ Department of Motor Vehicles as well as the American Automobile Association (AAA).

You cannot buy an IDP outside the UK, so get one before you travel.

If you still have a paper driving licence, you must take another form of photo ID, such as your passport. You can also exchange your paper driving licence for a photocard licence.

Hire car companies often have stricter requirements for their customers, such as a year of driving experience, a higher minimum age and holding an IDP.

Vehicle safety

When travelling by car, you should:

• check weather conditions before a long car journey, particularly in mountainous, isolated or desert areas where services may be limited
• not sleep in your car by the road or in rest areas
• avoid leaving any items on display in your car
• stay on main roads
• use well-lit car parks

If you’re in an accident, ask any other drivers involved to follow you to a public place and call the police.

Petrol stations

Petrol stations that do not display the price of fuel usually charge considerably more than the national average. They’re often close to tourist destinations and airports. Make sure you know the price of fuel before using these services.

Air travel

Before you travel, check the security measures you’re likely to face at the airport on the Transportation Security Administration (TSA) website. If you have a medical condition or disability and need assistance, contact TSA Cares.

To monitor airport conditions in the US, check the Federal Aviation Administration website.

Extreme weather and natural disasters

Find out what you can do to prepare for and respond to extreme weather and natural hazards. 

Snowstorms

Snowstorms can disrupt critical infrastructure, and cause power cuts, or delays and cancellations in major transport hubs. Contact your travel company or airline before you travel.

Hurricanes

The Atlantic hurricane season normally runs from June to November. The Pacific hurricane season normally runs from May to November. Hurricanes can affect coastal regions, Hawaii and Guam. The South Pacific tropical cyclone season normally runs from November to May and can affect American Samoa.

The US National Oceanic and Atmospheric Administration (NOAA) predicts that there is a very high likelihood of an “above-normal Atlantic hurricane season” in 2024. Travellers to the USA during the hurricane season should check the websites of local, State and Federal agencies (such as the National Oceanic and Atmospheric Administration) for the latest conditions. You should also be aware of the possibility of disruption to flights.

You should:

• monitor approaching storms on the US National Hurricane Center website
• follow instructions from local authorities, including evacuation orders from the Florida Division of Emergency Management.
• visit the Federal Emergency Management Agency (FEMA) website for information on preparing for extreme weather and evacuating
• check with your airline or travel agent about possible disruption to flights or airport services and follow their advice

Earthquakes

While earthquakes can happen anywhere without warning in the US, Alaska, California, Hawaii, Oregon, Puerto Rico, Washington and the entire Mississippi River Valley are at higher risk for earthquakes.

The FEMA website has advice about what to do before, during and after an earthquake.

Tornadoes

Tornadoes can happen anytime depending on weather conditions. The FEMA website has advice about what to do before, during and after a tornado.

Volcanic eruptions  

There is volcanic activity across parts of the US with Alaska, Hawaii, California, Washington and Oregon having the largest number of active volcanoes. You should follow the advice of local authorities, including any evacuation orders.

The FEMA website has advice about what to do before, during and after a volcanic eruption.

Wildfires

Forest and brush fires (wildfires) are a danger in many dry areas, particularly in canyons, hills and forests. High winds can mean fires spread rapidly.

You should:

• monitor local media and weather reports
• follow the advice of local authorities, including any evacuation orders
• be careful in areas recently affected by wildfires, as there may be mudslides during heavy rainfall

For more information visit the National Interagency Fire Center and Fire Research and Management Exchange System websites.

For information about wildfires in California, see the CAL FIRE website.

Arctic travel

Parts of the US are in the Arctic Circle, including some very remote areas of land and sea. Emergency medical assistance and search and rescue are limited in these areas. See Arctic travel safety advice.

Before you travel check that:

• your destination can provide the healthcare you may need
• you have appropriate travel insurance for local treatment or unexpected medical evacuation

This is particularly important if you have a health condition or are pregnant.

Emergency medical number

Dial 911 and ask for an ambulance.

Contact your insurance or medical assistance company quickly if you’re referred to a medical facility for treatment.

Vaccine recommendations and health risks 

At least 8 weeks before your trip:  

• check the latest vaccine recommendations for the US (or the US Virgin Islands, Puerto Rico and American Samoa, Guam and the Northern Mariana Islands)
• see where to get vaccines and whether you have to pay on the NHS travel vaccinations page

See what health risks you’ll face in the US (or the US Virgin Islands, Puerto Rico and American Samoa, Guam and the Northern Mariana Islands), including:  

• Zika virus
• West Nile virus

Altitude sickness is a risk in parts of the US. Read more about altitude sickness on TravelHealthPro. 

Medication

The legal status and regulation of some medicines prescribed or bought in the UK can be different in other countries.

You cannot take some prescription drugs into the US. The US Food and Drug Administration provides information on bringing medicines into the US.

UK prescriptions are not valid in the US. To get pharmacy drugs, you need a prescription from a US provider (available from an urgent care facility, emergency room or a doctor).

TravelHealthPro explains best practice when travelling with medicines.

The NHS has information on whether you can take your medicine abroad.

Healthcare in the US

Medical treatment is expensive and there are no special arrangements for British visitors.

Some hospitals ask non-US residents to pay a deposit when admitted. Send any requests for funds to your travel insurance provider first; only pay the hospital if you’re advised to do so by your travel insurance company. Your medical care will not be affected while your claim is processed.

Medical facilities in American Samoa are basic and you may need medical evacuation by air ambulance to Hawaii, New Zealand or Australia.

Make sure you have adequate travel health insurance and accessible funds to cover the cost of any medical treatment abroad and repatriation.

Travel and mental health

Read FCDO guidance on travel and mental health. There is also guidance on TravelHealthPro.

The Foreign, Commonwealth & Development Office (FCDO) cannot provide tailored advice for individual trips. Read this travel advice and carry out your own research before deciding whether to travel.

Emergency services in the US

Telephone: 911 (ambulance, fire, police).

Contact your travel provider and insurer

Contact your travel provider and your insurer if you are involved in a serious incident or emergency abroad. They will tell you if they can help and what you need to do.

Refunds and changes to travel

For refunds or changes to travel, contact your travel provider. You may also be able to make a claim through insurance. However, insurers usually require you to talk to your travel provider first.

Find out more about changing or cancelling travel plans, including:

• where to get advice if you are in a dispute with a provider
• how to access previous versions of travel advice to support a claim

Support from FCDO

FCDO has guidance on staying safe and what to do if you need help or support abroad, including:

• finding lawyers in the US
• dealing with a death in the US
• being arrested in the US
• getting help if you’re a victim of crime
• what to do if you’re in hospital
• if you are affected by a crisis, such as a terrorist attack

Contacting FCDO  

Help abroad   

See how to get help from the UK government abroad including in an emergency.  

Help in the UK   

You can call FCDO in London if you need urgent help because something has happened to a friend or relative abroad.   

Telephone: 020 7008 5000 (24 hours)   

Find out about call charges 

Get travel advice updates   

Sign up to get email notifications when this travel advice is updated.   

Follow FCDO:  

• travel advice on X 

• travel advice on Facebook