Visa Letter

Official Invitation Letter

We’re excited to welcome international attendees to OTC! If you require a visa to travel to the United States, you may download an official invitation letter to support your visa application.

Download the Official OTC Electronic Invitation Letter

We strongly encourage you to begin your visa application process as early as possible.

Please note: It is the sole responsibility of each attendee to secure the necessary documentation for entry into the United States. The invitation letter does not guarantee visa approval, nor does it imply any financial commitment or assistance from OTC. OTC is unable to contact embassies or consulates on your behalf, submit documents directly to visa offices, and cover any travel-related expenses.

Applying for a Visa

Traveling to the United States (US) involves additional advanced planning. Plan ahead to determine whether you will require a visa to enter the US. The following information will assist you in obtaining a visa.

Review visa wait times and then visit your local US embassy or consular office website where you will apply for your visa. There you can find out how to schedule an interview appointment, pay fees, and any other instructions.

Plan on an interview at the embassy or consulate, which is required for most visa applicants. As part of the visa interview, a quick fingerprint scan should be expected. Applicants who need additional screening are informed during the application process.

Prior to your scheduled interview date, you can complete the visa application online.

Important: Give yourself as much time as possible to apply for and obtain your visa. See below for updates on which Visa Waiver Country nationals must now apply for a visa.

Visa Waver Program

For those traveling to the US without a visa from the Visa Waiver Program (VWP) countries, an electronic passport (e-Passport) is required. Learn which countries participate in the Visa Waiver Program (VWP).

ESTA is Required: The Department of Homeland Security is now enforcing compliance of the Electronic System for Travel Authorization (ESTA) requirement for VWP travelers. A valid ESTA approval is required for all VWP travelers who are entering the United States by air or sea.

If approved, the authorization is good for two years and can be renewed. Travelers no longer have to fill out an I-94W form before each trip.

Notice: Nationals of VWP countries who are also nationals of or who have traveled on or after 1 March 2011 to Iran, Iraq, Sudan, or Syria are no longer eligible to travel to the United States under the Visa Waiver Program. These individuals will still be able to apply for a visa using the regular immigration process. Learn more to determine if you are affected.

Please note: the aforementioned information is a general guideline for travel to the US. Because travel requirements may change, OTC recommends that attendees contact their local embassy to ensure they have proper documentation.

Global Entry

Global Entry Trusted Traveler Network Members are encouraged to proceed and use a Global Entry kiosk on their arrival into the US.

All passengers eligible to apply for the US CBP Global Entry Trusted Traveler Network Program are highly encouraged to do so.

US citizens, US lawful permanent residents, and citizens of select countries are eligible for Global Entry membership. Find out which countries are eligible.

Your Flight and Arrival

Please check if your departure airport is one of 10 international airports where electronic devices larger than a smartphone will not be allowed as a carry-on item into the US. See which airports are affected. These devices must be placed in a checked bag.
For visitors arriving to the US via Bush Intercontinental Airport (IAH), take advantage of our dedicated OTC line in the Immigration Hall. Look for OTC directional signage on-site.