If you're travelling from the UK to the USA by air or sea, even if just passing through, you'll need to fill out an Electronic System for Travel Authorisation (ESTA) form in advance.
This guide explains what an ESTA is, how to get it, how long it lasts for, what to be wary of and how to avoid paying more than the official $14-per-person fee.
In this guide
The five ESTA need-to-knows
You MUST complete an ESTA, even if passing through
Most people going to the States by air or sea WILL need to fill out an ESTA form. If you haven't, even if you're only meant to be in transit, you may be denied boarding or can even be sent straight back home. See Who should complete the ESTA for more info.
Obviously some people DO need a visa instead of an ESTA, for example if they're staying in the US for a very long time or working. In that case see the US Embassy website for the rules and full help.
You can only fill it out online
You must fill out an ESTA application online, which means for those without web access you'll need to find a friend, relative or colleague to do it for you. Once you've done it, make sure you keep a note of your reference number somewhere safe. Better still, print the authorisation page (see How to complete an ESTA).
It costs $14, but ensure you pay the cheapest way
All accepted applications have a fee of $14 each ($4 if you're rejected); that's $56 (around £48) for a family of four. Ensure you pay with the right piece of plastic to avoid being charged a foreign exchange 'load' fee on top by your bank. See Pay with the right card for more info.
Watch out for shyster ESTA sitesWhen Googling ESTA, be warned you may be directed to sites that pretend to be the official web page and charge you an additional fee to process your application. Always use the official ESTA site. See Shyster Sites for more on this.
You need to renew after two years
If you already have an ESTA but need a new one (for example, if you've lost your passport, it's expired, or your existing authorisation has expired), the only way to renew is to complete a new application and get a new reference number. If you're unsure if you're still covered, check when yours expires on the ESTA website.
Dual national of, or since 1 Mar 2011 travelled to, Iran, Iraq, Libya, Somalia, Sudan, Syria or Yemen? You'll need to apply for a visa. This applies even if you have a British passport, unless travel was for diplomatic or military duties, in which case you'll need to contact the US Customs and Border Agency to check (or you can check your ESTA status if you already have one).
ESTA is an online system that tells you in advance whether you're eligible to travel to the United States under the Visa Waiver Program (VWP).
It replaced the old system of filling out a green I-94W piece of paper (commonly thought of as the Visa Waiver form) on a plane into the US. With that method, you'd only find out on arrival if US security decided you didn't fit under the VWP, based on what you put on the form and any further questions asked.
Now travellers have to complete an ESTA and know in advance whether they qualify to travel or not, minimising the possible loss of plane fares, hotels and more.
An ESTA is required for everyone entering the US by air or sea. If you cross a land border, via Canada or Mexico, then you need to complete a handwritten I-94W form, costing $6 per person, unless you already have an approved ESTA.
ESTA approval doesn't guarantee you entry
It's important to understand successfully applying for an ESTA doesn't mean you're automatically allowed to enter the USA. It just establishes that you're 'eligible to travel'.
Only a US Customs and Border Protection officer at the point of entry can decide whether you're actually allowed in or not. He or she may decide that you don't fit the VWP criteria after all. It's completely at their discretion.
Pay the $14 fee with the right plastic
ESTA applications have a $14 fee attached to them - that's $56 for a family of four.
Four dollars covers the ESTA administration and, rather bizarrely, $10 goes to a fund to promote US tourism Ė ironic as perhaps a better way to promote US tourism would be not to charge people who want to visit.
This isnít a visa charge for entry, itís a charge for getting permission to attempt to enter the country. (Incidentally, most US visitors to the UK donít have to pay anything.)
Avoid foreign exchange card fees
The system only accepts payment via MasterCard, Visa, Discover (JCB, Diners Club), American Express and PayPal. If your ESTA's rejected, you'll still be charged $4 (the admin fee) for applying.
Most of these types of plastic contain hidden charges, such as adding a 'load' onto the exchange rate when spending, and even charging interest from the moment you make a transaction.
You can beat this by using a specialist foreign spending card that won't penalise you. For all the current top cards, see our Travel Credit Card guide.
How to apply for an ESTA
Just before booking flights or accommodation, the very first thing to do is to apply for your permit to travel, just in case you're rejected (so you don't lose the flight or hotel money) or forget nearer the time of the journey.
Simply visit the US Department of Homeland Securityís special ESTA web page. The instructions are available in a choice of languages but your responses must be in English. Itís far from a slick website so pay careful attention as you complete each page. It should only take about five minutes.
Youíll be asked for your UK contact details, including passport number and expiry, plus the address where you're staying in the States.
The latter can be added or amended at a later time, but approximate info is often sufficient. A full list of what you'll need to provide and help on how to answer the questions you'll be asked is on the US Department of Homeland Security website.
You may be told within seconds if your application has been accepted or rejected. Otherwise, you'll be asked to check your application status later, as a decision can take up to 72 hours.
An ESTA lasts for two years, or until your passport expires, whichever comes first. Once it runs out, you'll need to apply for a new one. See the ESTA feedback thread for past application experiences.
Make sure you print the page or note the reference number
Although you donít need to present the reference number at Border Protection when you land on US soil, print it out and bring it to the airport. That's because some airlines require the printout upon check-in, so check with yours. Rather frustratingly, it isn't emailed to you.
However, if you do lose it, it's possible to get it back on the ESTA website. Click 'Retrieve my application' and enter your name, passport number and date of birth. This is also a handy way to check if you're still covered by a previous ESTA, as the site will also tell you when your ESTA expires.
You can ONLY apply online
This authorisation can only be given via online application. US Customs and Border Protection says a friend, relative, travel agent or third party can complete an ESTA on behalf of an individual. So if you know someone without internet access, please help them register if theyíre making a trip to the States.
It does seem bizarre that the US is effectively saying you need the internet to visit. Itíd be awful if, for example, an older non-web user didn't hear about this and was unprepared if they needed to make an emergency trip.
Avoid bogus websites
Watch out for websites demanding a fee for the ESTA. Search the internet for ĎESTAí and youíll discover many that claim to submit an application on your behalf.
Not only will you be paying money unnecessarily, you can't be certain it'll be a legit submission and acceptance, so you may still get turned away when you get to the US.
The US Department for Homeland Security says it canít stop this. But its logo is trademarked, so only if you see this will it be legit (though the scam websites do have very good imitations). The easiest thing to remember is: use the link in this guide and it's the official route.
The official logo, sourced from ESTA
You can't 'renew' it, you must reapply
All ESTAs have an end date; either two years from being granted or when your passport expires, whichever is sooner. If yours runs out, or you need a new one if you get a new passport, simply apply again in exactly the same way you did the first time.
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Don't risk travelling without it
If you haven't completed the ESTA before travelling, or you did but were declined, you may not be allowed to board your outbound flight.
It's worth remembering that anyone can apply for ESTA on your behalf and, although the Department of Homeland Security recommends giving at least 72 hours for a decision to be made, it often only takes seconds.
Of course, if you're rejected, you'll lose the cost of your flights and any associated expenses such as hotel bookings and car hire (if they're non-refundable), as insurance providers will almost certainly not cover you for this.
What if my ESTA is rejected?
Other things to consider
Who's eligible and who needs ESTA
You need to fill one in:
If you're a citizen of one of the 38 countries which are part of the US's Visa Waver Program (the UK is, see the US Department of Homeland Security's website for a list).
If you don't have a US visitor's visa.
If you won't stay in the US for longer than 90 days.
If you're only travelling to the States for business or pleasure.
If you have a return or onward bound ticket.
On behalf of all infants and children.
If you don't qualify for an ESTA and need a visa, for example if you're staying in the US for longer than 90 days or will be working there, see the US Embassy website for full help.
A green I-94W form is mostly no longer needed
Travellers entering the US by air or sea with an approved ESTA won't have to complete the I-94W form. The I-94W (costing $6) will only be required if your ESTA's been rejected. It's also needed if you're arriving by land (via Canada or Mexico) without an approved ESTA.
Lost your reference number and need to make an amendment?
If you've got an ESTA already but need to update it or make a correction, you can do this on the ESTA website. There's no fee - just scroll down and put in your application number, date of birth and passport number.
If you've lost your ESTA number you can also find this online. Just scroll down to 'Retrieve your application number' and enter your name, passport number and date of birth. This is also a handy way to check if you're still covered by a previous ESTA, as the site will also tell you when it expires.
Get a new passport, get a new ESTA
If you've lost your passport, it was stolen or it's significantly damaged and must be replaced, your new passport will have a new number. So, you must apply for a new ESTA.
If you're renewing your passport, your ESTA will have the same expiry date (if it hasn't expired already) so you'll have to reapply with the new passport number too.
You need an ESTA if travelling to Puerto Rico, Hawaii or the US Virgin Islands
As Puerto Rico, Guam, the Commonwealth of the Northern Mariana Islands and the US Virgin Islands are governed by the US, you need ESTA before travelling to them too.
You'll also need one if travelling to Hawaii or Alaska - which, while far-flung, are both US states.
Travelling by land from Canada or Mexico? You don't need ESTA
It's only necessary for travel by air or sea. An I-94W form, costing $6, is still required if you're arriving by land or sea if you don't have an approved ESTA.