A forward‐masking situation was investigated where more energy added to the masker decreased the threshold of the signal. The signal was a single sinusoid. The masker contained two frequency components: one at the same frequency as the signal, and one at a variable frequency. For certain frequencies and intensities of this variable masker component the threshold of the signal was lower than if that component were not present.This decrease in threshold is unmasking. Unmasking is interpreted as being caused by the suppression of the fixed masker component by the variable masker component, thus producing less masking at the signal frequency. The basic pattern of masking and ummasking was qualitatively similar to the pattern of pulsation thresholds observed by Houtgast [Acustica 29, 168‐179 (1973). Unmasking was not observed at absolute threshold or in a simultaneous masking situation. Unmasking was observed at all signal frequencies tested (0.5–6.0 kHz) and was not dependent on the phase of the masker components or the phase between the masker and the signal. When the frequency of the variable masker component was less than the signal frequency, unmasking was dependent on only the intensity of the variable component. However, when the variable frequency was greater than the signal frequency, unmasking was dependent on the difference in intensity between the two masker components. The existence of unmasking in a forward‐masking situation does not depend on whether or not the masker and signal are turned on and off abruptly or smoothly. These characteristics of unmasking are not in conflict with the assumption that this effect is caused by the variable masker component suppressing the other masker component.Subject Classification: [43]65.58, [43]65.68, [43]65.50.