After graduating high school, Orr attended Wake Forest University, where he served as chairman of the Honor Council and set a new fundraising record as chairman of the Brian Piccolo Cancer Fund Drive. He earned his Bachelor of Arts degree with several academic honors and held numerous leadership positions. Following his undergraduate education, Orr attended the University of Alabama School of Law in Tuscaloosa, where he was elected as chief justice of the Honor Court, served as senior editor of the law review, and was on the Moot Court board. While in law school, he taught freshman English to undergraduates and regularly volunteered with Big Brothers/Big Sisters and the Community Soup Bowl.

Upon receiving his law degree in 1989, Orr made an unexpected career choice by joining the Peace Corps in 1989 instead of pursuing a traditional legal career. He was assigned to a remote Himalayan village called Khandbari in Nepal, where he lived primitively with no indoor plumbing and dirt floors for 27 months. During his service, he taught children and trained teachers in a one-room, dirt-floor structure and had to hike several days to reach various villages. While in Nepal, Orr noticed the plight of young village girls who were married off at early ages and unable to continue their education. With financial help from friends and family in the U.S., he established a college scholarship program to benefit female village students, which has helped over 200 village students attend college.

After completing his Peace Corps commitment in 1992, Orr returned to Decatur, Alabama, where he joined the law firm of Harris, Caddell and Shanks, P.C., practicing corporate law. He became active in his community and served as president of several non-profit organizations. In 1997, after five years at the law firm, Orr resigned his partnership to join Habitat for Humanity International with the mission to develop the program in Southeast Asia. He spent three months in Americus, Georgia, learning the basic requirements necessary to start a program on the other side of the world.

Before leaving for his assignment with Habitat, Orr met his future wife, Amy Wallace Bethshares, also from Decatur, who was a student at Florida State University obtaining her master's in Russian and Eastern European Studies. After a brief return to the United States during his time abroad, the couple married. Orr's work with Habitat for Humanity included serving as a new country developer in Bangladesh and as a staff attorney in the Pacific Ocean region of Asia from 1997 to 2001.

Upon returning to the United States, Orr began working for Cook's Pest Control in 2001, where he currently serves as Executive Vice President. His responsibilities include overseeing finance and accounting, human resources, property management, legal matters, technology, marketing, and advertising. In August 2017, he was named Executive Vice President and Chief Administrative Officer as part of key leadership changes at the company.

In 2006, at the age of 42, Orr ran for the Alabama State Senate in District 3, which is centered in Decatur and encompasses all of Morgan County and small parts of Limestone and Madison counties. He won both the Republican primary with 84% of the vote and the general election with 62% of the vote in what was one of the most expensive races in Senate history up to that time. Since his first election, Orr has not faced significant opposition and has been re-elected multiple times, most recently in 2022.

During his time in the Senate, Orr has held several leadership positions, including Chairman of the Senate Finance and Taxation Education Committee and previously Chairman of the Senate Finance and Taxation General Fund Committee. He has sponsored and passed legislation addressing high school dropout rates, putting the state's checkbook online, improving campaign finance reporting, removing racist language from the state constitution, and supporting volunteer firefighters and free medical clinics. Orr was instrumental in the formation and development of the Robotics Technology Park, The Alabama Center for the Arts, and the Alabama School for Cyber Technology and Engineering.

In June 2024, Orr was recognized by the Alabama Fire College for his heroic response that saved the life of Senator Tim Melson during a cardiac event while on an education and economic development trip to Korea and Vietnam in July 2023. This experience led Orr to sponsor the "Sen. Tim Melson Act" which expands CPR training in public schools to include hands-on training in the technique and use of automated external defibrillators.

Arthur Orr and his wife Amy are members of First Bible Church in Decatur and have two children- a son named Jack and a daughter named Anna. Orr continues to serve as both a State Senator and as Executive Vice President at Cook's Pest Control while remaining active in various community and state organizations.