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Summary Virginiamycin (VM), a compound with proven performance‐promoting properties in pigs, can also be considered as sow performance enhancer. The present dose titration study investigates the long‐term effects of VM on gilt/sow and litter performance. A total of 140 healthy gilts, in 35 sets of 2 + 2 siblings each, were used in this trial; gilts in each set were randomly allocated to the four treatments (35 gilts per each treatment group): VMO = negative control, virginiamycin 0 mg/kg, VM20 = virginiamycin 20 mg/kg, VM40 = virginiamycin 40 mg/kg and VM60 = virginiamycin 60 mg/kg of feed. VM was added to the gilt/sow feed for a period starting from 6 months of age up to conception of the fourth parity, covering three complete breeding cycles (pregnancy, lactation and weaning‐to‐conception interval). The feed given did not contain any other antibacterial agent or performance enchancer. Piglets were given exactly the same quantity of creep feed from the fifth day onwards; it did not contain any antibacterial agent or performance enchancer. The lactation period was the same in all gilts/sows (21 days). Results indicate that VM supplementation of the feed improved gilt/sow performance by: (i) increasing (P < 0.05) the mean body weight at each farrowing, (ii) decreasing (P < 0.05) the mean weight loss from farrowing to weaning, and (iii) decreasing (P < 0.05) the mean weaning‐to‐conception intervals. VM supplementation of gilt/sow feed also resulted in improved litter size and litter performance in terms of: (i) a higher (P < 0.05) mean number of piglets born alive at each birth, (ii) a higher (P < 0.05) mean number of piglets weaned, (iii) a higher (P < 0.05) mean piglet body weight at each birth, and (iv) a higher (P < 0.05) mean piglet body weight at each weaning. These beneficial effects of VM were more pronounced in the VM40 group.