Visa Information


Valid photo ID such as a passport, driver’s license, military ID card or other state or federally issued form of ID to confirm identity.

3-1-1 rule for airport security:
3.4 oz. bottles of liquid or gel products in a 1 quart bag and each passenger is permitted 1 bag.

United States Visa Advisory
The United States has updated its visa policy for increased security. As a result, it now takes longer to obtain a visa. Advance planning by travelers is essential to avoid frustration and disappointment.

Review your visa status to find out if you need a U.S. visa or a visa renewal.

Plan to submit your visa application well in advance of your intended departure date.
Contact your nearest U.S. embassy or consulate for current time estimates and recommendations.
Visit the embassy or consular section website to find important information on how to schedule an interview appointment, finger scanning – if required – and pay fees. An interview is required as a standard part of processing for most visa applicants.
Visa Waiver Program (VWP)

The Visa Waiver Program (VWP) enables nationals of 38 participating countries to travel to the United States for tourism or business (visitor [B] visa purposes only) for stays of 90 days or less without obtaining a visa. The program was established to eliminate unnecessary barriers to travel, stimulating the tourism industry, and permitting the Department of State to focus consular resources in other areas. VWP eligible travelers may apply for a visa, if they prefer to do so. Nationals of VWP countries must meet eligibility requirements to travel without a visa on VWP, and therefore, some travelers from VWP countries are not eligible to use the program. VWP travelers are required to have a valid authorization through the Electronic System for Travel Authorization (ESTA) prior to travel, are screened at the port of entry into the United States, and are enrolled in the Department of Homeland Security’s US-VISIT program.

Currently, 38 countries participate in the Visa Waiver Program, as shown below:

Andorra Estonia Italy
the Netherlands South Korea Australia
Finland Japan New Zealand
Spain Austria France
Latvia Norway Sweden
Belgium Germany Liechtenstein
Portugal Switzerland Brunei
Greece Lithuania San Marino
Taiwan Chile Hungary
Luxembourg Singapore United Kingdom
Czech Republic Iceland Malta
Slovakia Denmark Ireland
Monaco Slovenia

For more information, see

Problems when obtaining a Visa

If you encounter a longer than anticipated delay or other difficulties in obtaining a US visa to attend the AP-S/USNC-URSI Symposium and Radio Science Meeting, you may benefit from the procedure described on the following Web site of the US National Academies of Sciences, Engineering, and Medicine

This site provides a link to a questionnaire that can be completed if

If you satisfy these criteria, it is STRONGLY urged that you complete the questionnaire. Doing so will enable the US National Academies to report urgent cases to the US Department of State, and this in the past has at times facilitated completion of the visa process.


A passport with a validity date of at least six months beyond the applicant’s intended period of stay in the U.S. is required. If more than one person is included in the passport, each person desiring a visa must make a separate application. Please check with the website, https:/, to confirm that your passport is compliant. Temporary Passports will likely merit special scrutiny. To avoid complications, check with your local US consular offices, well ahead of your intended departure dates.

Visa Letters

A visa support letter can be provided for authors and registered attendees upon request.

There are 2 types of visa support letters available from APS/URSI 2018: A Formal Acceptance Letter and an Official Registration Confirmation and Invitation.

Formal Acceptance Letter

The Formal Acceptance Letter is available to authors of accepted papers and will be sent only by email. The document is a full-color PDF file on conference letterhead, eletronically signed by the conference chair and conference organizer.

Formal acceptance letters will be sent only to authors of record on accepted submissions, and only to the email address that was entered for that author during the initial paper submission. If there are mistakes in the author entry, please email us at with a correction.

Request a Formal Acceptance Letter

Official Registration Confirmation and Invitation

The Official Registration Confirmation and Invitation is available to persons who register for the conference, and whose registration payment has been received. The document is a full-color PDF file on conference letterhead, eletronically signed by the conference chair and conference organizer.

During registration, an individual will be able to order a hard-copy invitaion letter with a real ink signature of a conference organizer to be express-mailed within a few days, with a fee to cover the express postage. An emailed version of the letter is also available at any time for no cost.

Request a Official Invitation Letter


This information is provided in good faith but travel regulations do change. The only authoritative sources of information are the U.S. Government website

Foreign Consulates in the Boston area:

Austria, Brazil, Canada, Cape Verde, Columbia, Dominican Republic, El Salvador, France, Germany, Greece, Haiti, Ireland, Israel, Italy, Japan, Mexico, Peru, Portugal, Spain, Thailand, Venezuela.

Cambridge: United Kingdom, Switzerland.

Newton: South Korea.

Honorary consulates in Boston: Bolivia, Denmark, Finland, Hungary, Lebanon, the Netherlands, Norway Pakistan, Poland,Romania, Sweden, Turkey.


Additional Information: