1H and 13C NMR spectra of symmetric and asymmetric bis‐spiropyrans, Series 1‐3, were completely assigned. Especially, the 1H assignment of asymmetric spiropyrans was achieved by utilizing 1H–1H COSY and nOe experiments. All of the carbons in the dye molecules were investigated through a combination of heteronuclear 2D‐shift correlation spectroscopy (HETCOR), together with an attached proton test (APT)