Summary: It is already known that unifiable formulas in normal modal logic \(\mathbf{K}+\square^2\bot\) are either finitary or unitary and unifiable formulas in normal modal logic \(\mathbf{Alt}_1+\square^2\bot\) are unitary. In this paper, we prove that for all \(d\geq 3\), unifiable formulas in normal modal logic \(\mathbf{K}+\square^d\bot\) are either finitary or unitary and unifiable formulas in normal modal logic \(\mathbf{Alt}_1+\square^d\bot\) are unitary.