Travel to the United States is not always for tourism, business, study, employment, or permanent immigration. There are other visa categories that serve specific purposes, including transit through the US, receiving medical treatment, undertaking official government duties, temporary religious work, working as a crewmember, and certain humanitarian or special situations. This guide outlines these other visa categories and what they cover.
Section A: Transit Visas
Foreign nationals travelling through the United States on their way to another country may need a transit visa. This ensures lawful entry and exit while in the US, even if the stop is brief. Travellers from Visa Waiver Program (VWP) countries must still obtain ESTA approval even when only transiting.
1. Transit Visa (C)
A C visa is required when the only purpose of entering the United States is to transit to another destination. Holders cannot use the visa for tourism or any activities beyond what is necessary to complete onward travel, and they are not permitted to extend their stay for sightseeing.
2. Visitor Visa (B)
If the transit involves leaving the airport or undertaking any short visits within the United States, a B visa may be required. The B category allows limited, short-term activities such as brief visits during a layover, subject to standard visitor rules.
3. Visa Waiver Program (VWP)
Nationals of designated VWP countries may transit the United States without a visa if they obtain ESTA approval and meet all program requirements. Entry is limited to a maximum stay of up to 90 days, which also applies where the purpose includes transit only.
Section Summary: Transit through the United States is covered either by the Transit (C) visa, the Visitor (B) visa where short visits are planned, or the VWP with ESTA for eligible nationals. The correct option depends on eligibility, whether the traveller will leave the airport, and compliance with VWP limits.
Section B: Medical Treatment
Foreign nationals can travel to the United States to receive private medical treatment. Entry for this purpose requires proof of treatment arrangements, confirmation from a US medical provider, and evidence that the applicant can cover the costs of care and related expenses. Applicants must also demonstrate they will return home after treatment is completed.
1. Visitor Visa (B)
The B-2 visitor visa is most commonly used for medical travel. Applicants must present documentation from a US healthcare provider outlining the planned treatment and demonstrate financial means to pay for medical services, transport, and living costs during their stay.
2. Visa Waiver Program (VWP)
Nationals of VWP countries may enter for medical care under ESTA approval, provided their stay does not exceed the 90-day limit and they meet all programme requirements. Supporting evidence of treatment and funding may still be requested at the port of entry.
Section Summary: Medical treatment in the United States usually requires a B-2 visitor visa with supporting documentation. VWP travellers may receive care if eligible, but their stay is capped at 90 days and ESTA approval is mandatory.
Section C: Official Government and Diplomatic Travel
The United States issues dedicated visas for foreign officials, diplomats, representatives of international organisations, and military personnel on duty. These visa types reflect the unique status of official travel and extend to eligible dependants.
1. Diplomatic and Foreign Official Visas (A)
A visas are issued to accredited diplomats and government officials travelling to the United States on official assignments. Immediate family members may also qualify for derivative visas linked to the principal applicant’s status.
2. International Organization Employees (G) and NATO Visas
G visas apply to employees of recognised international organisations, while NATO visas apply to representatives of the North Atlantic Treaty Organization. Both visa types extend to spouses and children of eligible applicants. Applicants must be entering the United States to carry out official duties with their organisation.
3. Foreign Military Personnel
Foreign military staff posted in the United States are covered under A-2 and NATO visa classifications. These visas may be renewed if an assignment is extended, and eligible dependants may also qualify for derivative visas. Military personnel cannot use visitor visas for official duty travel.
Section Summary: Diplomatic and official travel visas include A visas for diplomats and officials, G and NATO visas for international organisation staff, and A-2/NATO categories for military personnel. Dependants are also eligible under these classifications where requirements are met.
Section D: Religious, Crewmember, and Humanitarian Visas
Several other visa categories apply to specific circumstances, such as religious work, crew duties on ships or aircraft, and humanitarian or refugee-related admissions. These categories each have strict eligibility and procedural requirements.
1. Religious Worker Visa (R)
The R visa allows religious workers and ministers to enter the United States temporarily to work for a qualifying US-based religious organisation. The organisation must be a bona fide non-profit, tax-exempt entity recognised in the United States. Applicants must show evidence of their role and their affiliation with the religious organisation.
2. Crewmember Visa (C-1/D)
Crewmembers employed on ships or aircraft require a C-1/D visa when travelling to the United States in connection with their duties. This visa is strictly tied to the individual’s work as crew and cannot be used for extended shore leave or activities outside their employment role.
3. Humanitarian and Special Situations
The United States provides humanitarian entry in specific situations, including refugee admissions and follow-to-join provisions for family members of recognised asylees and refugees. These categories are not applied for in the same way as regular visas, but through specialised refugee and asylum processes administered by USCIS and the Department of State.
Section Summary: Religious workers, crewmembers, and those in humanitarian situations may qualify under these specialised categories. Each requires strict compliance with eligibility rules, with humanitarian cases following dedicated refugee or asylum procedures.
FAQs
1. Do all medical visitors need a visa?
Most do, unless they are nationals of a Visa Waiver Program country. Even then, ESTA approval is required and the stay must not exceed 90 days. Applicants must also show medical necessity and the ability to pay for treatment.
2. Can a transit visa be used for short sightseeing?
No. A C transit visa is strictly for passing through the United States. Travellers wishing to leave the airport for sightseeing or visits must apply for a B visa or, if eligible, use the Visa Waiver Program with ESTA approval.
3. What is the difference between A and G visas?
A visas are issued to accredited government officials and diplomats on official missions, while G visas are for staff of recognised international organisations. Both categories may extend to eligible dependants.
Conclusion
The United States offers a wide range of visa categories beyond the common routes for tourism, business, study, and employment. These additional categories cover transit, medical treatment, official diplomatic and government travel, religious work, crewmember duties, and humanitarian admissions. Each visa type has specific eligibility rules and documentary requirements. Selecting the correct visa and complying with its conditions is essential to ensure lawful entry and avoid disruption to travel plans.
Glossary
| Transit Visa (C) | Allows passage through the US en route to another country; does not permit tourism or extended stay |
| Visitor Visa (B) | Used for tourism, medical treatment, and certain transits; requires supporting evidence for medical cases |
| Visa Waiver Program (VWP) | Permits short visits without a visa for nationals of designated countries, with ESTA approval, up to 90 days |
| A Visas | For accredited diplomats and government officials on official assignments; may extend to eligible dependants |
| G Visas | For employees of recognised international organisations, including their dependants |
| NATO Visas | For NATO representatives and eligible family members travelling on official duty |
| Religious Worker Visa (R) | Temporary visa for ministers and religious workers employed by a bona fide US non-profit religious organisation |
| C-1/D Visa | For crew of ships and aircraft entering the US for work duties; not valid for extended shore leave |
| Humanitarian Programs | Special US government processes for refugees, asylees, and their eligible family members |
Useful Links
| US Visas – Official State Department |
| Other Visa Categories – State Department |
| ESTA Application – Visa Waiver Program |
| USCIS Humanitarian Programs |
Author
Founder & Principal Attorney Nita Nicole Upadhye is a recognized leader in the field of US business immigration law, (The Legal 500, Chambers & Partners, Who's Who Legal and AILA) and an experienced and trusted advisor to large multinational corporates through to SMEs. She provides strategic immigration advice and specialist application support to corporations and professionals, entrepreneurs, investors, artists, actors and athletes from across the globe to meet their US-bound talent mobility needs.
Nita is an active public speaker, thought leader, immigration commentator, and immigration policy contributor and regularly hosts training sessions for employers and HR professionals.