S&P 600 component
|Headquarters||Huntsville, Alabama, USA|
|Tom Stanton CEO|
|Revenue||US$636.8 Million (FY 2016)|
|US$34.7 Million (FY 2016)|
|US$35.2 Million (FY 2016)|
|Total assets||US$667.2 Million (FY 2016)|
|Total equity||US$479.5 Million (FY 2016)|
Number of employees
ADTRAN was founded by Mark C. Smith and Lonnie McMillian, and began operations in 1986. The AT&T divestiture of the Regional Bell Operating Companies (RBOCs), with restrictions that effectively barred their manufacturing of equipment, created an opportunity for companies such as ADTRAN to supply network equipment, both to the seven RBOCs and the new and independent telephone companies in the United States.
ADTRAN adapted telephony technology for use in enterprise-wide area networks. ADTRAN has become a supplier of local loop access and deployment products for fiber, DS3, T1/E1, wireless T1/E1, digital subscriber line (HDSL, HDSL2, HDSL4, SDSL, SHDSL), Frame Relay, Asynchronous Transfer Mode (ATM), Integrated Services Digital Network (ISDN), and Digital Data Service (DDS) digital services. ADTRAN supplies multi-service access platforms and Integrated Access Devices (IADs) for converged voice and data networks.
According to Computer Business Review, ADTRAN enhanced its portfolio of carrier ethernet products with the addition of three new multi-service modular routers supporting a services-enabled sustained throughput of up to 250Mbit/s.
In December 2011 ADTRAN announced a plan to buy the Broadband part from Nokia Siemens Networks. In 2012 ADTRAN’s closing of acquisition of the Nokia Siemens Networks Broadband division was finished.
ADTRAN's U.S. corporate headquarters is located in Huntsville, Alabama, in Cummings Research Park, the second largest research park in the United States. ADTRAN has engineering research and development centers in:
- Huntsville, Alabama, USA
- Portland, Oregon, USA
- Hyderabad, India
- Berlin, Germany
- Greifswald, Mecklenburg-Vorpommern, Germany
- Munich, Bavaria, Germany
- Warsaw, Poland
- Melbourne, Australia
Sales and support offices are located throughout the U.S. and around the world. 
- About Us; TBE website; retrieved April 25, 2007
- ADTRAN (ADTN) annual SEC income statement filing via Wikinvest
- ADTRAN (ADTN) annual SEC balance sheet filing via Wikinvest
- "Hot Growth Special Report 2006". Business Week. June 2006. Archived from the original on 28 May 2009. Retrieved 2009-07-10.
- "Archived copy". Archived from the original on 2011-07-23. Retrieved 2014-04-29.CS1 maint: archived copy as title (link)
- "Historical Data - NASDAQ-100 Index". NASDAQ. Retrieved 2009-07-10.
- "Mark C. Smith". The Huntsville Times. March 29, 2007. Retrieved 2007-06-21.
- "ADTRAN Co-Founder, Chairman Passes Away Archived November 19, 2007, at the Wayback Machine"
- Maistre, Ray (December 12, 2011). "Adtran to Buy NSN's Broadband Unit". Light Reading. Retrieved 2018-03-30.
- Wauters, Robin (December 12, 2011). "ADTRAN Buys Nokia Siemens Networks' Fixed Line Broadband Access Business (400 People)". TechCrunch. Retrieved 2018-03-30.