The Atomic Credit Union was founded November 28, 1955, nearly 25 years after the credit union movement began in Ohio. Originally, the credit union was established to meet the financial needs of 'all retired or permanently employed personnel engaged in the operation of; maintenance of; or construction at the Atomic Plant site,' additionally, immediate family members were also permitted to join the credit union. The credit union's field of membership remained status quo until a small credit union in Scioto County, Southern Ohio Savings Credit Union, Inc. became insolvent and was presented to Atomic in the early 1990's as a merger opportunity. Although Southern Ohio Savings Credit Union, Inc. was relatively small in asset size, it held a very lucrative field of membership charter. .