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A business visa (either B1 or WB ,if from a visa waiver country) is the required visa to obtain in order to enter the US, attend the conference and receive any type of funding or reimbursement. These types of activities are not allowed on a tourist visa (B2 or WT). In particular, it is imperative that you enter the US with a business visa to obtain any type of funding or reimbursement from the conference.

There are many different requirements to obtain a visa to enter the U.S. or other countries. Some embassies may request a conference attendee to present a letter from the conference to verify their intentions to attend the specific conference. It may also be necessary to verify that the requester has paid the registration fee in full.

Visa applications are currently subject to a greater degree of scrutiny than in the past. Many applicants may be required to appear in person for an interview as part of the visa process. Applicants affected by these procedures are informed of the need for additional screening (Administrative Processing) at the time they submit their visa application and will be advised to expect delays. Therefore, attendees are advised to apply for their visa no later than 3-5 months prior to the conference.

Obtaining a Visa

If you are planning to travel to the United States to attend the conference and live in a country that requires a Visa, we urge you to apply for one as early as possible. Below are suggestions to help you secure the correct Visa.

  • Apply at the appropriate location at least 3-5 months before intended travel. You can check on-line for the wait times for appointments.
  • Be prepared to allow inkless fingerprinting and digital photographs upon entry to the US.
  • Be accurate and specific in completing your application. Avoid mistakes. If needed, attach an additional explanation letter.
  • Attach evidence of your previous visits to the United States and of your intended return trip to your home country.
  • Acquire a police clearance, if possible.
  • Bring all documentation proving your home country connections. Suggestions include: past visas, bank accounts, family, professional position, home ownership, and marriage license.
  • If you are presenting a paper or speaking at the meeting or are receiving an award or grant, bring copies of correspondence confirming that.
  • Bring your letter of invitation from the conference
  • You will need to apply for a Business visa.

Click here for information on Temporary Visas to participate in a conference or other temporary travel to the United States.

Click here for the United States Visa application procedures.

Note: A Visa only allows you to travel to the US.  You will still have to be admitted at your point of entry.  Click here for information from Homeland Security on the Entry Process. Click here for a description from U.S Customs and Border Protection of the process for entering the United States.

Additional Information: U.S. visa policy permits citizens of certain countries to travel to the U.S. without a visa, when they meet certain requirements, under U.S. laws. Please click here for more information about which counties participate in the Visa Waiver Program. Visa Waiver attendees need to secure a WB (Business) stamp at the US port-of-entry.

Invitation Letters

All conference letters of invitation are only provided to attendees who are planning to participate and attend the conference. Please email us at to request a letter of invitation and/or a letter for visa application:

You will need to provide the following information in your request:

  • Your full name (Family name and given name)
  • Gender
  • Date of Birth
  • Passport Number
  • Degree (M.D., Ph.D, etc.)
  • Job Title (Professor, Lab Director, etc.)
  • Organization
  • Full mailing address

Multiple Travelers from One Institution

In order to expedite the application process and reduce processing costs, it is requested that if you will be traveling from an institution that will likely be sending more than one person, please work with your institution to gather all requests with the required information at one time to be submitted.

Note: In some cases, Visa Offices will not accept electronically transmitted invitation letters.