The Multidimensional State Boredom Scale (MSBS) is a promising new self-report measure of state boredom. Two condensed versions of the scale have also been introduced. This study helped explore the psychometric qualities of these scales, using a large sample of Australian adults (N = 1,716), as well as two smaller samples (N = 199 and N = 422). Data analyses indicated strong convergent validity and very high internal consistency for the scales. Test–retest reliability over a 6- to 8-day period was moderately high. Confirmatory factor analyses of the MSBS authors’ suggested factor structure indicated good fit for this model. However, some of the data analyses raise questions as to whether the scale includes meaningful subfactors. Overall, the MSBS (and Short Form) is recommended for researchers who wish to assess state boredom.