Many Americans traveling abroad find that it is necessary to travel to an American Embassy or Consulate in order to request services such as Passport renewal, adding of visa pages, notarial services, or Consular Reports of Birth Abroad (CRBA). Many of these requests can be made at an American Citizen Services Section of the US Embassy or US Consulate-General.

Meanwhile, every year many foreign nationals from around the globe travel to American posts abroad to apply for visas and other travel documents granting permission to travel to the United States. Some visa seekers only wish to remain temporarily in the US on non-immigrant visas such as the B-1 visa (Business Visa), the B-2 visa (Tourist Visa), the F-1 visa (Student Visa), or the J-1 visa (Exchange worker visa). Generally, applications for the aforementioned visa categories can be made at a non-immigrant visa unit within the Consular Section of the US Embassy or US Consulate-General. Applicants are usually required to make an appointment in advance to apply for these types of visas.

Some foreign nationals wish to travel to the United States for business purposes. Depending upon the circumstances of the individual applying for admission to the USA, a business traveler may be issued a non-immigrant or an immigrant visa. The L-1 visa, the E-1 visa, the E-2 visa, the EB-5 visa, the EB-4 visa, the EB-3 visa, the EB-2 visa, the EB-1 visa, and the H-1B visa are all business visa categories commonly sought by foreign nationals. Generally, a business travel unit  within the Consular Section of a US Embassy or Consulate-General abroad is responsible for adjudicating such applications.

Some foreign nationals seek visa benefits based upon a relationship to a US Citizen or lawful permanent resident. One of the most commonly sought US family based visas is the immigrant visa based upon marriage to an American Citizen, these types of visas are generally classified as a CR-1 visa or an IR-1 visa. Fiancees of US Citizens may be eligible to apply for a K-1 visa (US fiance visa). Furthermore, those married to Americans sometimes seek a US K-3 visa. K-1 visas and K-3 visas are generally adjudicated by an Immigrant visa unit, notwithstanding the fact that they are non-immigrant visa categories as they are treated as immigrant visas since the applicants have immigrant intent.

For related information please see: US Immigration Asia.

It should be also noted that although these USCIS estimated processing times can provide a general framework for understanding the time frames for petition adjudication by USCIS, these estimates do not necessarily reflect the estimated time frame for the entire US visa process especially if the unique circumstances of a given case requires Consular Processing of a US visa application at a US Embassy or US Consulate abroad.

For a married couple seeking an IR1 visa or a CR1 Visa for a foreign spouse of US Citizen the process begins at the USCIS where the initial petition will be adjudicated. Assuming USCIS approves the initial petition, then the petition will be forwarded to the National Visa Center (NVC). NVC will require certain documents before forwarding the application to a US Embassy or Consulate abroad where a foreign spouse must undergo an interview prior to the Consular Officer making a decision regarding visa issuance. In some cases, the Consular Officer may approve the visa application at the interview. Meanwhile, in some circumstances, the officer may deny the application (especially where a ground of inadmissibility is found to exist in the case and under such circumstances the applicant must be granted an I-601 waiver, or something similar, prior to the application receiving further favorable treatment). In some cases, the officer may simply find that some further evidence of the relationship or documentation pertaining to the foreign national is lacking and will thereby deny the application pursuant to section 221(g) of the Immigration and Nationality Act. Under these circumstances, the 221(G) denial may be overcome by presenting further evidence to the Consular Officer and upon their finding that the relevant requirements have been met the application may be approved.

As one can infer from the above example, the USCIS estimateed  processing times may not accurately reflect the total time it may take to obtain a US visa since the process is sometimes more complex than simple USCIS petition approval.