Tenn. Code Ann. § 47-12-107: Continuing guaranty or suretyship agreements - Future obligations

(a) Notwithstanding any law to the contrary, no continuing guaranty or suretyship agreement which guarantees the performance of all present and future obligations shall be enforceable against a surety unless the individual or organization agrees in writing to guarantee the future obligation; provided, that no additional writing or guarantee shall be required, at the time of the advance, for advances which are permitted pursuant to the terms of the guaranty or suretyship agreement.

(b) This section only applies when the indebtedness of the principal debtor arises from personal obligations, and do not apply when the indebtedness arises from commercial obligations.