A bstract We combine SO(10) Grand Unified Theories (GUTs) with 4 modular symmetry and present a comprehensive analysis of the resulting quark lepton mass matrices for all simplest cases. focus on case where three fermion families in 16 dimensional spinor representation form triplet ? 3 ? , Higgs sector comprising single multiplet H 10 fundamental one field $$ \overline{\Delta } <mml:math xmlns:...