The Visa Waiver Program (VWP) allows 41 nations to enter the US for 90 days without a visa.  People from nations including the UK, Andorra, Australia, Austria, and belgium  The following countries can now enter the united states without a visa for a period of 90 days: Brunei, Chile, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Israel, Ireland, Italy, Japan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, the Netherlands, New Zealand, Norway, Poland, Portugal, Qatar, Republic of Korea, Romania, San Marino, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, and Taiwan. 

The VWP permits the majority of the aforementioned nations' citizens or nationals to visit the united states for 90 days or less for business or pleasure without requiring them to apply for or receive a visa. Before entering the united states, travelers must obtain a current Electronic System for Travel Authorization (ESTA) permission. One can still apply for a visitor (B-1 or B-2) visa if they still want a visa in their passport.

What other requirements are to be met?
Travelers in these categories are required by the VWP and Terrorist Travel Prevention Act, 2015, to apply for and receive a visa before entering the United States:
 

 - Nationals of the VWP nations who traveled to or were in Iran, Iraq, Libya, Somalia, Sudan, Syria, Yemen, or the Democratic People's Republic of Korea on or after march 1, 2011.
 
- Individuals from the VWP nations who traveled to or were in cuba on or after january 12, 2021.
 
- Nationals of the VWP nations who are also nationals of Iran, Iraq, Syria, cuba, the Democratic People's Republic of Korea, or Sudan.
 
To enter the US without a visa, one must fulfill all VWP requirements.  


Travellers should have a valid ESTA
Under the VWP, U.S. Customs and Border Protection (CBP) uses an online system called the Electronic System for Travel Authorization (ESTA) to assess a person's eligibility to enter the country for business or pleasure.  Only those from VWP nations who have a valid ESTA approval before boarding the mode of transportation they have selected to visit the united states are permitted to enter the country without a visa.
 
To apply for it or find out more about the system, go to the ESTA website.

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