The Governors of the U.S. Postal Service appointed Tammy Hull as the third Inspector General of the U.S. Postal Service on November 29, 2018. Prior to her appointment, Ms. Hull served as the Acting Inspector General for the U.S. Postal Service Office of Inspector General (OIG) since February 2016. She also served as the Deputy Inspector General from November 2011 to February 2016. In years prior, Ms. Hull served as the Assistant Inspector General for Audit. Ms. Hull came to the OIG in November 2005 as an Audit Director.

Ms. Hull started her government career at the Internal Revenue Service Inspection Service and transitioned with them as a part of the Treasury Inspector General for Tax Administration (TIGTA), established in early 1999. During her career at TIGTA, she was an audit manager in Dallas, TX for several years before coming to Washington D.C. as the Director of the Office of Management and Policy.

Since January 2023, Ms. Hull also serves as the Vice Chairperson of the Council of Inspectors General on Integrity and Efficiency (CIGIE).

Ms. Hull holds a Bachelor of Accounting and Business Administration degree from W. J. Bryan College in Dayton, TN and is a Certified Public Accountant.