Eastman Credit Union Eastman Credit Union is a not-for-profit financial cooperative headquartered in Kingsport, Tennessee. Established in 1934, ECU has grown to serve over 348,000 members across Tennessee, Virginia, and Texas. ECU is ranked 34 on the list of the largest 100 credit unions in the United States. History ECU was chartered on September 10, 1934, initially serving employees of the Tennessee Eastman Chemical Company