Abstract The Wnt protein family plays a critical role in cell development, with each Wnt protein interacting differently with the Wntless (Wls) membrane protein through distinct binding residues. A direct comparison and elucidation of the molecular mechanisms underlying Wnt–Wls binding across the diverse Wnt family remain challenging, owing to variations in sequence length and amino acid composition among Wnt proteins, which can affect their binding affinity and trafficking efficiency via Wls.