iLOV is a flavin mononucleotide (FMN)-binding fluorescent protein (FbFP) with excitation and emission spectra similar to those of the green fluorescent protein (GFP). Importantly, contrary to GFP, iLOV fluoresces independently of molecular oxygen, making its usage in low-oxygen conditions possible. Moreover, iLOV is smaller than GFP, increasing the likelihood of retaining full functionality when creating fusions with proteins of interest. Nonetheless, GFP remains to date the most widely used FP in molecular biology, also due to the availability of multiple spectrally tuned variants allowing multi-color imaging experiments. To expand the range of applications of iLOV, spectrally tuned red-shift variants are desirable to have reduced phototoxicity and better tissue penetration. Here we experimentally tested two iLOV mutants, iLOV L470T/Q489K and iLOV V392K/F410V/A426S, which were previously computationally proposed to have red-shifted excitation and emission spectra. We found that only the triple mutant has moderately red-shifted excitation and emission spectra. Both mutants exhibit strongly decreased brightness, which impedes their employment in live cell imaging. Finally, we show that the single V392K mutation suffices to red-shift the emission spectrum as well as abolishes fluorescence of iLOV.