Plasma membrane blebs, or giant plasma membrane vesicles (GPMVs), serve as excellent biomimetics for studying the compositional complexity of native cell membranes. However, current supported membrane models often lack the stability or submembrane reservoir necessary for extended functional studies. This work presents a proof of concept for the formation of tethered bilayer lipid membranes (tBLMs) using blebs derived from human lung cancer cells (A549). We report that successful fusion of blebs into planar tBLMs on gold substrates requires a significantly higher density of tethering anchors (60 mol % WC14) than that required for synthetic liposomes.