Visa Requirements

Regarding Temporary Visitors to the U.S., the U.S. Department of State states the following:

International visitors add greatly to our nation's cultural, education and economic life. We continue the proud tradition of welcoming visitors to the United States, with secure borders and open doors.

However, the U.S. state of Arizona has a law (SB 1070) that make it wise to always carry your passport and visa with you. But there should be no need to panic about this, as according to the travel information section of the Arizona Travel Facts website, “In regards to SB 1070, please note that Arizona police officers will not ask for identification unless some violation of Arizona law has occurred.” The Arizona governor’s website also says that police should not ask to see identification unless some other violation has occurred.

Most Canadian citizens and many citizens from Visa Waiver Program countries can come to the United States (U.S.) without a visa if they meet certain requirements. All Visa Waiver Program travelers must present a machine-readable passport at the U.S. port of entry to enter the U.S. without a visa; otherwise a U.S. visa is required. See important information about additional digital photograph and e-passport requirements for VWP travelers. Other foreign citizens will need a nonimmigrant visa.

Nonimmigrant visas are for international travelers (citizens of other countries), coming to the U.S. temporarily. The visa, placed in your passport when issued, allows you to travel to a U.S. port-of-entry (airport, for example) and request permission of the Department of Homeland Security (DHS), Customs and Border Protection immigration officer to enter the U.S. A visa does not guarantee entry into the U.S.

International travelers come to the U.S. for a wide variety of reasons, including tourism, business, medical treatment and certain types of temporary work. The type of visa needed is defined by immigration law, and relates to the principal purpose of your travel. For an overview of the types of nonimmigrant visas available under immigration law, please see our Visa Types for Temporary Visitors webpage. The Consular Officer at the U.S. embassy or consulate will decide what kind of visa you need, when you apply.

Advance planning can smooth the visa application process for you. Apply for your visa well in advance of your travel!

Important steps to remember:

1. Review your visa status, and find out if you need a U.S. visa or a renewal.
2. Review the Visa Wait Times information for interview appointments and visa processing at each embassy and consular section worldwide available on our website. Visit the embassy or consular section website where you will apply for your visa to find out how to schedule an interview appointment, pay fees and any other instructions.
3. Plan on an interview, as well as quick inkless fingerprint scans at the U.S. embassy or consulate, which is required for most visa applicants. Some visa applications require additional administrative processing, which requires some additional time. Applicants are advised when they apply.

See the Visa Types for more information about visas required for temporary visitors to the U.S.

ACM Visa Support Letters

The Association for Computing Machinery does not issue formal invitation letters for visas to attend ACM sponsored conferences. We can however issue a visa support letter. For Visa support letters, please send all requests to the Office of SIG Services supportletters@acm.org with the following information:

1. Name and mailing address as it appears on your passport
2. The name of the conference you wish to attend
3. Your Registration Confirmation Number
4. If you are the author of any papers accepted for the conference, please provide the title
5. A valid fax number and current mailing address (**Please note: visa support letters are NOT issued via email)

Please see the ACM Visa Support Letters web page for updates to this policy.