The crystal structures of two thiacalixarene derivatives anchoring thiadiazole functional groups at lower rim, C₆₀H₇₂O₄S₁₂N₈ (1), C₆₄H₈₀O₄S₁₂N₈ (2), have been determined by single crystal X-ray diffraction. The thiacalix[4]arene framework in both 1 and 2 adopts the 1,3-alternate conformation. Compound 1 forms a 1-D chain by weak hydrogen bonding (C-H$\cdots$N) interactions between two thiadiazole groups in two different molecules. The chains are further connected to form a 2-D network through sulfur-sulfur (S$\cdots$S) interactions. The lattice water molecules which exist as dimers by forming hydrogen bonds (O-H$\cdots$O) promote a 3-D supramolecular structure through weak hydrogen bonding (O-H$\cdots$S) interactions between the lattice water dimers and the 2-D networks. On the other hand, compound 2, based on dimer which is formed by weak hydrogen bonding (C-H$\cdots$S) interactions, is extended to a 1-D chain through sulfur-sulfur (S$\cdots$S) interactions. The dimers of lattice methanol molecules linked by hydrogen bonds (O-H$\cdots$O) act as bridges to link the 1-D chains into a 2-D network through weak hydrogen bonding (C-H$\cdots$N) interactions.