ESTA allows US Customs and Border Protection (CBP) to screen travelers seeking to enter the United States under VWP prior to their arrival in the United States. DHS notes, however, that an authorization to travel to the United States under ESTA is not a determination that the person ultimately is admissible to the United States. That determination will be made by a CBP officer only after an applicant for admission is inspected by the CBP officer at a U.S. port of entry. ESTA is not a visa or a process that acts in lieu of any visa issuance determination made by the Department of State. Travel authorization under ESTA allows a VWP participant to travel to the United States, but does not guarantee that the person will be admitted into the U.S. upon arrival.

Although ESTA does not become mandatory until January 12, 2009, it is already up and running on a voluntary basis. ESTA will become mandatory for VWP travelers on January 12, 2009. After that date, VWP travelers will not be allowed to board a flight or cruise to the United States without an ESTA authorization. VWP travelers will be able to apply for ESTA authorization at any time prior to travel to the United States, but are encouraged to do so at least 72 hours before traveling.

The information submitted by the person in his/her ESTA application will be checked by CBP against all appropriate databases, including, but not limited to, lost and stolen passport databases and appropriate watchlists. If a person does not provide the information required or provides false information in his/her ESTA application, or if any evidence exists indicating that the person is ineligible to travel to the United States under VWP or that permitting such travel poses a law enforcement or security risk, CBP may deny the ESTA application. Without an ESTA approval, the person will not be allowed to board the aircraft. According to DHS, ESTA will reduce the number of travelers who are determined to be inadmissible to the United States during inspection at a port of entry, thereby saving, among other things, the cost of return travel to the carrier, inspection time, and delays and inconvenience for the traveler.

Each ESTA travel authorization will be valid for a period of up to two years. A person may travel to the United States repeatedly within the validity period using the same ESTA authorization. Travelers whose ESTA applications are approved, but whose passports will expire in less than two years, will receive travel authorization that is valid only until the expiration date on the passport. A VWP traveler must obtain a new ESTA authorization if any of the following occur: (1) The person is issued a new passport; (2) The person's name changes; (3) The person changes his or her gender; (4) The person's country of citizenship changes; or (5) The person's answer to any of the ESTA questions changes.

Although DHS is allowed to charge a fee to use ESTA, at this time, payment of a fee will not be required. There is no appeal or judicial review available for an adverse ESTA determination. A determination under ESTA that an alien is eligible to travel to the United States under the VWP may be revoked at the discretion of the DHS.

In estimating the costs of the ESTA program from 2008 to 2018, DHS has stated “that costs to air and sea carriers to support the requirements of the ESTA program could cost $137 million to $1.1 billion over the next 10 years depending on the level of effort required to integrate their systems with ESTA, how many passengers they need to assist in applying for travel authorizations, and the discount rate applied to annual costs. Costs to foreign travelers could total $1.1 billion to $3.5 billion depending on traveler volume, their value of time, and the discount rate applied.” “The estimated annual public cost for ESTA is $63.8 million. This is based on the number of responses (17,000,000) x a response time of 15 minutes x an average hourly rate of $15 = $63.8 million.” [Federal Register: June 9, 2008]

At the 2008 Annual Conference of the American Immigration Lawyers Association, a DHS representative stated the U.S. has 15 million VWP visitors per year, an average rate of 60,000 visitors per day. He said DHS expects ESTA to result in 30 denials per day. ESTA in now available online at https://esta.cbp.dhs.gov/esta/.