Spectra of gas phase HNO 3 were collected in the region 2000-8500cm - 1 using Fourier-transform infrared spectroscopy. This region is dominated by the ν 1 O H stretching mode but also contains many previously unreported combination bands and overtones. This work marks the first observation of Fermi resonance the 2ν 1 O H stretching overtone. Previously unobserved bands were assigned and integrated intensities were obtained. For bands already reported in the literature, comparisons of relative intensities are presented when possible. This work gives a brief discussion on the trends in overtone intensities and on mode mixing in HNO 3 in relation to previous experimental and theoretical studies.