The Commissioner is appointed by the President of the United States, with the consent of the U.S. Senate, for a five-year term.

[5] On December 4, 2024, President-elect Donald Trump announced his intention to nominate Billy Long to serve as Commissioner of the Internal Revenue Service.

[6][7] Daniel Werfel was the latest Commissioner of Internal Revenue, having been sworn in on March 13, 2023.

[9] The Commissioner's duties include administering, managing, conducting, directing, and supervising "the execution and application of the internal revenue laws or related statutes and tax conventions to which the United States is a party" and advising the President on the appointment and removal of a Chief Counsel of the IRS.

[11] One of the Commissioner's most important responsibilities with respect to the internal revenue laws is setting the Treasury Regulations administered by the IRS.