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Visa and Immigration Information

For International Patients/Caregivers

The NIH Clinical Center conducts clinical research on a broad spectrum of diseases and health problems. Patients are selected by Institute physicians on the basis of their illness if the ailment is being studied by the Institute. On occasion, the NIH accepts international patients as clinical research participants. Those patients arriving from abroad will need to obtain a B-2 Temporary Visitor’s Visa prior to entering the United States for medical treatment.

The following immigration information is broken down into six parts in order to better illustrate the steps required to enter and remain in the United States for the purpose of medical treatment: Part 1 discusses the consular process prior to entering the U.S.; Part 2 reviews the U.S. arrival procedure; Part 3 concerns the maintenance of B-2 status while in the U.S.; Part 4 denotes information regarding stay extensions; Part 5 includes important reminders; and Part 6 discusses general immigration information and resources.

Part 1: Consular information needed before you arrive at NIH

All international patients receiving treatment at NIH as well as their caregivers need a B-2 visa issued by the United States (U.S.) Consulate or Embassy in their country of origin.

The B-2 visa allows international patients and caregivers to enter the U.S. and obtain an extension to stay, if needed, to receive treatment at NIH.

In determining entitlement to the Visitor Visa, the consular office will assess the following factors:

  • Whether the patient maintains a residence outside of the United States which they do not intend to abandon. (The patient's place of actual dwelling is their residence regardless of intent.)
  • Whether the patient intends to enter the United States for a period of specifically limited duration. (The period of stay itself is not controlling provided the intended stay has a time limitation and is not indefinite.)
  • Whether the patient seeks admission for the purpose of engaging in legitimate activities (no unlawful or criminal activities).

It is the responsibility of the patient and/or caregiver to overcome the presumption of immigration intent and provide evidence that they will return to their country of origin once treatment/evaluation ends.

NIH research teams assist with the Visa application process by sending the patient an invitation letter. If the patient needs a caregiver, the letter includes the caregiver's name and the reason why he/she must accompany the patient. This letter will communicate the NIH's intent to treat the patient's specific condition, and to the extent possible, detail the projected length of treatment.

The consular officer may also ask the patient for a medical diagnosis and confirmation from a local, consular-approved physician, explaining the nature of the ailment and the reason the patient requires treatment in the United States.

In addition to the NIH invitation letter, the visa applicant must provide the consular officer with documents showing ties to the country of origin. For example, they can demonstrate permanent employment, meaningful business and financial connections, close family ties, or social and cultural associations, which will indicate a strong inducement to return to the country of origin. The applicant must also provide proof of financial support while the patient stays in the U.S. for treatment. For instance, the applicant should verify that the have sufficient funds to cover expenses for their visit and departure from the U.S.

If for any reason, the patient is determined to be inadmissible for a nonimmigrant visa (NIV), they should contact the NIH's Division of International Services (DIS) at for further assistance.

A visa is a travel document, represented by a stamp placed in an applicant's passport, issued by the State Department in a consular office abroad. A visa can be issued for one (1) or multiple (M) entries and can have an expiration date and time between one day and 10 years. The expiration date on the visa is the last day the applicant is allowed to enter the U.S. Once this date has expired, they cannot use this visa again to enter the U.S. and must request a new visa. Additionally, please note that visa reciprocity rules may apply and vary by country.

Once granted, the B-2 Visa does not guarantee your right to enter or remain in the United States, or to acquire a new visa in the future. A visa simply allows you to apply for admission at a U.S. port of entry, but the ultimate decision on whether or not, and under which statutes, you will be admitted rests with the U.S. Customs and Border Protection of the Department of Homeland Security.

Sample US visa stamp

A sample of a U.S Visa MRV document (not valid for travel)
*The final section at the bottom of the stamp is a machine read only reference section.

The Visa Waiver Program (VWP)

Visitors who have passports from countries with an option to enter the U.S. under the "Visa Waiver Program" (VWP), which waives the entry visa requirement, should be aware of the strict, non-renewable 90-day limit they are permitted to stay in the U.S.

Once the 90-day period has expired, patients who use the VWP must leave the U.S. before they can re-enter the U.S. under that program.

Therefore, all international patients and their caregivers who come from countries offering the VWP or other border entry exceptions should get a B-2 visa when visiting the U.S. for treatment at the NIH.

NIH will be unable to help patients or their caregivers extend their stay if they come under the VWP or other program that waives an entry visa.

Because medical care events are not always predictable, getting a B-2 visa is important for patients and caregivers even when they do not expect to stay longer than 90 days. With a B-2 visa, the patient or caregiver can extend a stay in the U.S. without needing to leave the country.

For more information about the VWP and those passport holders who may be eligible to use the program, please visit the U.S. Customs and Borders Protection's website for the most up-to-date information:

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Part 2: Arrival to the United States

Upon arrival, you will be inspected by a U.S. Customs and Border Protection (CBP) officer. The CBP officer will review your documents and admit you to the U.S. under B-2 status for a specific period of time. The CBP officer will stamp your passport with an arrival and departure stamp and enter your biographical and visa information into an electronic record system. The electronic record, known as an I-94 "Arrival/Departure Record," can be accessed online and specifies the date your status expires in the U.S. You must leave the U.S. or extend your stay prior to the expiration date on the I-94 record..

Please take a moment after your arrival to locate and print your I-94 record found online at The Admit Until date on your I-94 indicates the date your status in the U.S. expires. You must depart the U.S. prior to your "Admit Until" date unless your medical care requires that you stay in the U.S., in which case an extension request must be filed with the U.S. Citizenship and Immigration Services before the I-94 expiration date.

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Part 3: Maintaining B-2 status while in the U.S.

It is important to remember that as a B-2 Visitor for medical treatment, you are limited to activities that involve your medical treatment and general tourist type activities. Engaging in inappropriate activities will lead to violations of your immigration status and make you subject to denial of extensions, deportation and denied future re-entry.

To avoid problems with immigration issues while in the U.S., please:

  • Maintain a valid passport at all times. If your passport will expire while you are in the U.S.,you may apply and obtain a new passport from your home country's embassy in the U.S.
  • Engage only in activities permitted by your B-2 status. U.S. Federal laws prohibit any individuals under B-2 status to:
    • Enroll in primary, secondary or university studies. (Enrolling in classes while in B-1/B-2 status will result in a status violation. Individuals in B-1 or B-2 status, who have violated their nonimmigrant status by enrolling in classes, are not eligible to extend their B status or change to another status. These regulations provide no exceptions. In addition, enrolling a child in classes may cause them and their family members to be refused a visa to enter the U.S. in the future.)
    • Be employed while in the U.S. (Employment is the condition of having paid work or performing any actions that generate income.)
  • Apply for an extensions of stay before your "Admit Until" date is reached. Typically the Division of International Services will assist you with this application.

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Part 4: Information about extending your stay to complete treatment

Patients and caregivers whose stays are deemed medically necessary by the patient's medical team may be eligible for assistance in preparing requests for extensions of stay. If you have questions regarding this, please contact or call the Social Work department at 301-496-2381 and ask to speak to someone regarding nonimmigrant services.

Please contact the Social Work department four months prior to the expiration date on your I-94 record. If you continue to need medical treatment at the NIH, the Social Work department will make an appointment with a staff member to help you extend your stay.

Patients and caregivers must depart the U.S. upon completion of their treatment. If you remain in the U.S. after the end date of your I-94 record without submitting an extension request, it may cause problems with future visits to the U.S.

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Part 5: Important Reminders

NIH does not assist patients with issues unrelated to their medical stay at NIH.

Examples include:

  • Obtaining a "Green Card"
  • Paperwork related to a marriage, work permits or refugee or asylum requests
  • Extensions of stay for persons who entered the country under the Visa Waiver Program
  • Extensions for those who are not the patient or the caregiver.

Humanitarian Parole, also known as "Humanitarian Visa"

When the U.S. Department of State, through its consulate abroad, denies an applicant a B-2 visa, some applicants may be eligible to enter the U.S. by applying for Humanitarian Parole. This type of visa is issued by the Department of Homeland Security. A U.S. resident or U.S. citizen must sponsor the applicant. Complete information on obtaining Humanitarian Parole can be found at:

Humanitarian Parole, also incorrectly called “Humanitarian Visa,” is NOT recommended for patients who need to remain or receive treatment at NIH for an extended period of time. Once the time limit granted on the Humanitarian Parole expires, it is very difficult, and sometimes impossible, to obtain extensions of time. In that case, the applicant will need to return to his country of origin.

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Part 6: Immigration Information

The clinical center strives to provide international patients with immigration assistance to the best degree possible. To that extent, they have enlisted the services of Division of International Services (DIS) to provide applicable immigration services and updates. DIS has a staff of highly talented Immigration Specialist ready to assist. Please keep in mind, however, that rules and regulations may change without notice.

It is important that patients and caregivers refer to the Department of Homeland Security website for the most up to date policies and news:


Please contact DIS with any immigration process related questions at 301-496-6166 or email at Nonimmigration service question can be directed to the Clinical Center at

Please note: This information is provided for your assistance. No warranty is provided as to its accuracy or usefulness. It is not meant to replace the information from Federal agencies responsible for immigration services.

This information is prepared specifically for persons taking part in clinical research at the National Institutes of Health Clinical Center and may not apply to patients elsewhere. If you have questions about the information presented here, talk to a member of your health care team.

Products/resources named serve as examples and do not imply endorsement by NIH. The fact that a certain product/resource is not named does not imply that such product/resource is unsatisfactory.

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This page last updated on 01/22/2019

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