You are using an unsupported browser. This web site is designed for the current versions of Microsoft Edge, Google Chrome, Mozilla Firefox, or Safari.
The Office of the Federal Register publishes documents on behalf of Federal agencies but does not have any authority over their programs. We recommend you directly contact the agency associated with the content in question.
If you have comments or suggestions on how to improve the www.ecfr.gov website or have questions about using www.ecfr.gov, please choose the 'Website Feedback' button below.
If you would like to comment on the current content, please use the 'Content Feedback' button below for instructions on contacting the issuing agency
Enhanced content is provided to the user to provide additional context.
This content is from the eCFR and is authoritative but unofficial.
Navigate by entering citations or phrases (eg: 1 CFR 1.1 49 CFR 172.101 Organization and Purpose 1/1.1 Regulation Y FAR).
Choosing an item from citations and headings will bring you directly to the content. Choosing an item from full text search results will bring you to those results. Pressing enter in the search box will also bring you to search results.
Background and more details are available in the Search & Navigation guide.
| Use of United States Flag Air Carriers | 301 – 10.159 | |||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||
5 U.S.C. 5704; 5 U.S.C. 5707; 5 U.S.C. 5707, note; 40 U.S.C. 121(c); 49 U.S.C. 40118; Office of Management and Budget Circular No. A-126, revised May 22, 1992, 57 FR 22150.
FTR Case 2025-05, 90 FR 56893, Dec. 8, 2025, unless otherwise noted.
This content is from the eCFR and may include recent changes applied to the CFR. The official, published CFR, is updated annually and available below under "Published Edition". You can learn more about the process here.
Subscribe to: 41 CFR Part 301-10 Subpart B - Use of United States Flag Air Carriers
View the most recent official publication:
These links go to the official, published CFR, which is updated annually. As a result, it may not include the most recent changes applied to the CFR. Learn more.
Information and documentation can be found in our developer resources.
The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.
Learn more about the eCFR, its status, and the editorial process.
Anyone whose air travel is financed by U.S. Government funds must use a U.S. flag air carrier, except as provided in §§ 301-10.134, 301-10.135, and 301-10.136.
U.S. flag air carrier service is service provided on an air carrier holding a certificate under 49 U.S.C. 41102 (excluding a foreign air carrier operating under a permit), and which service is authorized by the carrier's certificate or by exemption or regulation. This also includes service provided under a code share agreement with a foreign air carrier in accordance with title 14, Code of Federal Regulations, when the ticket identifies the U.S. flag air carrier's designator code and flight number.
Employees are required by 49 U.S.C. 40118, commonly referred to as the “Fly America Act,” to use U.S. flag air carrier service for all air travel funded by the U.S. Government except as provided in §§ 301-10.135 and 301-10.136 or when one of the following exceptions applies. Exceptions can only be approved by the agency head or designated official.
(a) Use of a foreign air carrier is determined to be a matter of necessity in accordance with § 301-10.135.
(b) The transportation is provided under a bilateral or multilateral air transportation agreement to which the U.S. Government and the government of a foreign country are parties and which the Department of Transportation has determined meets the requirements of the Fly America Act.
(c) The employee is an officer or employee of the Department of State or an Executive branch employee under Chief of Mission authority, and travel is paid with funds appropriated to one of these agencies and the employee's travel is between two places outside the United States.
(d) No U.S. flag air carrier provides service on a particular leg of the route, in which case foreign air carrier service may be used, but only to or from the nearest interchange point on a usually traveled route to connect with U.S. flag air carrier service.
(e) A U.S. flag carrier involuntarily reroutes the employee's travel onto a foreign carrier.
(f) Service on a foreign air carrier would be three hours or less, and use of the U.S. flag carrier would at least double the employee's en route travel time.
(g) When the costs of transportation are reimbursed in full by a third party, such as a foreign government, international agency, or other organization.
(h) For travel solely outside the U.S., use of an available U.S. flag air carrier when compared to using a foreign air carrier will increase the number of aircraft changes the employee must make en route by 2 or more; or extend the travel time by 6 hours or more; or require a connecting time of 4 hours or more at an overseas interchange point.
(i) The employee is an officer or employee of the Department of State or an executive branch employee under Chief of Mission authority, and travel meets the requirements of 22 U.S.C. 4081a.
(a) Foreign air carrier service is deemed necessary when U.S. flag air carrier service is available but—
(1) Cannot provide required air transportation; or
(2) Will not accomplish the agency's mission.
(b) Necessity includes circumstances such as:
(1) Medical reasons, including reducing connections and potential delays for individuals needing medical treatment.
(2) Avoiding unreasonable risks to employee safety, which requires a case-by-case agency determination and written agency approval.
(3) Threats against U.S. flag air carriers, which must be supported by a travel advisory notice from the Federal Aviation Administration and Department of State.
(4) Threats against a Government employee or other travelers, which must have evidence supporting the threat that form the basis of the agency's determination and approval.
(5) Inability to purchase a ticket in the authorized service class on a U.S. flag air carrier, and there is an available seat in the authorized service class on a foreign air carrier.
(a) If a U.S. flag air carrier offers nonstop or direct service (no aircraft change) from origin to destination, the employee must use the U.S. flag air carrier service unless such use would extend travel time, including delay at origin, by 24 hours or more.
(b) If a U.S. flag air carrier does not offer nonstop or direct service (no aircraft change) between origin and destination, the employee must use a U.S. flag air carrier on every portion of the route where it provides service unless, when compared to using a foreign air carrier, such use would:
(1) Increase the number of aircraft changes made outside of the U.S. by 2 or more;
(2) Extend travel time by at least 6 hours or more; or
(3) Require a connecting time of 4 hours or more at an overseas interchange point.
Employees must provide a certification as required in this section and any additional documents specified by the agency. The agency will not pay the foreign air carrier fare without the required certification. The certification must include—
(a) Employee's name;
(b) Travel dates;
(c) Origin and destination;
(d) Detailed travel itinerary, including air carrier and flight number for each leg of the trip; and
(e) Statement explaining compliance with exceptions in § 301-10.134 or § 301-10.136, or a copy of the agency's written approval deeming foreign air carrier service necessary in accordance with § 301-10.135.
Employees will not be reimbursed for transportation costs incurred through improper or unauthorized use of foreign air carrier service.