U.S. Government ethics rules limit whether a U.S. Government employee can write letters of recommendation in support of visa actions for another individual. Some letters are permitted, but they must be personal letters and neither NIH letterhead nor NIH signature block may be used.​ 

Any individual at NIH who is asked to write a letter of recommendation in support of a visa action should take time to review the NIH policy, available on the NIH Ethics website. Please contact your Ethics Officer if you have any questions. 

Current Full-Time Equivalent (FTE) employees at the NIH can use the TALX system to provide proof of employment and income. See more about TALX on the NIH Human Resources website. Former FTE employees can refer to separate guidance on the NIH Human Resources website. 

Current or former non-FTEs at the NIH (e.g. Visiting Fellow, Special Volunteer, Guest Researcher, or Collaborator) should contact their NIH supervisor or Administrative Officer (AO) to obtain this verification. 

In general, DIS does not issue letters to NIH-sponsored foreign scientists for travel purposes (exception: scientists in TN status, see section on TN Travel Letters below). However, the NIH laboratory can provide an optional travel letter with a description of research activities at the NIH for scientists planning to travel internationally. 

DIS provides a template ICO travel letter.​ 

Note that DIS has additional travel guidance, including a Travel Tool on our website for J-1/J-2 Exchange Visitors and H-1B/O-1 scientists. ​
 

DIS issues an official invitation letter after processing an ICO’s request for a foreign national scientist to come to the NIH. The official letter will be signed by either the DIS Director or a DIS Immigration Specialist. Scientists who are new to the NIH should wait to make travel arrangements to the United States until they have received a copy of the scanned letter via email.    

An unofficial, tentative offer letter may be issued by the ICO to the incoming NIH foreign national scientist while DIS processes their initial request. This letter is for informational purposes only and cannot be used to make travel arrangements. ICO administrative staff may refer to the relevant NIH Manual Chapter per NIH designation for a template tentative offer letter. Note that final DIS approval is necessary before the foreign national scientist can begin any research at the NIH.​  

Foreign scientists who are citizens of Canada or Mexico may be eligible to gain entry into the United States under TN status for purposes of conducting research at NIH. DIS will make this determination after we receive a case request from the NIH IC. If the individual is eligible for TN status, DIS will issue a TN invitation/travel letter.  

Scientists in TN status at the NIH should always travel internationally with the most recently issued TN travel letter from DIS. Read more about TN status here.​