We investigated the possible contribution of signals carried by vestibular-nerve afferents to long-term processes of vestibular compensation after unilateral labyrinthectomy. Semicircular canal afferents were recorded from the contralesional nerve in three macaque monkeys before (horizontal (HC)=67, anterior (AC)=66, posterior (PC)=50) and 1-12 months after (HC=192, AC=86, PC=57) lesion. Vestibular responses were evaluated using passive sinusoidal rotations with frequencies of 0.5-15 Hz (20-80 ^o/s) and fast whole-body rotations reaching velocities of 500 ^o/s. Sensitivities to non-vestibular inputs were tested by: 1) comparing responses during active and passive head movements, 2) rotating the body with the head held stationary to activate neck proprioceptors, and 3) encouraging head-restrained animals to attempt to make head movements which resulted in the production of neck torques of up to 2 Nm. Mean resting discharge rate before and after the lesion did not differ for the regular, D(dimorphic)-irregular, or C(calyx)-irregular afferents. In response to passive rotations, afferents showed no change in sensitivity and phase, inhibitory cutoff, and excitatory saturation following unilateral labyrinthectomy. Moreover, head sensitivities were similar during voluntary and passive head rotations, and responses were not altered by neck proprioceptive or efference copy signals before or after the lesion. The only significant change was an increase in the proportion of C-irregular units post-lesion, accompanied by a decrease in the proportion of regular afferents. Taken together, our findings show that changes in response properties of the vestibular afferent population are not likely to play a major role in the long-term changes associated with compensation following unilateral labyrinthectomy.