The small protein GB1, where all valine residues were replaced by fluorinated analogues containing one or two CH₂F groups, produces ¹⁹F NMR (nuclear magnetic resonance) spectra with exceptional resolution. We establish a convenient strategy for their assignment and analyse the rotameric states of the CH₂F groups by virtue of three-bond coupling constants and a γ effect on ¹³C chemical shifts, which is underpinned by DFT (density functional theory) calculations. Transient fluorine–fluorine contacts are documented by through-space ¹⁹F–¹⁹F couplings.