In this paper, we give an almost complete classi cation of toric surface codes of dimension
less than or equal to 7, according to monomially equivalence. This is a natural extension
of our previous work [YZ], [LYZZ]. More pairs of monomially equivalent toric codes constructed
from non-equivalent lattice polytopes are discovered. A new phenomenon appears, that is, the
monomially non-equivalence of two toric codes C
P(10)7and CP(19)7
can be discerned on Fq, for all
q 8, except q = 29. This sudden break seems to be strange and interesting. Moreover, the
parameters, such as the numbers of codewords with di erent weights, depends on q heavily. More
meticulous analyses have been made to have the possible distinct families of reducible polynomials.