Visa Information

If you are traveling to the meeting from outside the United States, SSA recommends that you start the process of applying for a visa at least three months prior to the meeting. Security-related policies have greatly increased the processing time for visa applications.

Visa Waiver Program (VWP): Please note that the State Department has required citizens from VWP countries to obtain visas if they do not have machine-readable passports. One-time exemptions are no longer available to VWP nationals who do not possess a machine-readable passport or a non-immigrant visa.

Letters of invitation can be requested by sending your name, address, SSA membership ID number and a description of how you plan to participate in the meeting to If you want specific information included in your letter, please let us know. Letters are required for most visa processes.

The National Academies of Sciences maintains a website about visa-related issues and travel information for U.S. citizens and non-U.S. citizens.