Financial terms of the deal remained undisclosed.
The agreement was approved by the boards of both banks and it is expected that the transaction will complete during June 2013, pending receipt of regulatory approval.
Following completion of the transaction, the acquirer will have 1.2bn in assets and 24 branches throughout East and Central Texas.
The integrated trust departments will have more than $350m in assets under management, according to Citizens National Bank.
East Texas National president Cliff Bomer said that the acquisition will enable the bank to offer dedicated services to its customers in future.
Chartered in 1911, East Texas National Bank has been operating for more than 102 years maintaining a strong relationship with its customers in the region.
The bank manages full-service branches in Huntsville and Mexia, in addition to its main bank in Texas. The lender owns $150m in assets and $65m in assets under management in its trust department.
Headquartered in Henderson, Citizens National Bank is a locally owned, independent, community bank, serving the families and businesses of East Texas since 1930.
In December 2012, the bank purchased White Oak State Bank, as part of its strategy to boost its operations in Gregg County region.The latest acquisition marks its second deal in the past few months.
