This retrospective study examined ocular surface stability of donor eyes following conjunctival limbal autografts (CLAU). Forty-five eyes underwent CLAU with chemical burns being the most common indication. All but two eyes had just over 4 o’clock hours of CLAU segment transplanted from the donor to the recipient. One eye required only one CLAU segment (2 o’clock hours) for visual rehabilitation. One blind eye, as a result of multiple retinal detachments and failed surgeries, had 8 o’clock hours of CLAU segments transplanted to the recipient eye. None of the donor eyes showed clinical signs of limbal stem cell deficiency (LSCD) within the mean follow-up of 48.3 months. There were no significant changes from pre- to postoperative best corrected visual acuities. All donor eyes had stable ocular surface. The eye, which underwent 8 o’clock hours of CLAU, also showed no clinical signs of LSCD after 7.3 years of follow-up but developed band keratopathy. This study confirms CLAU as a valuable treatment option for eyes with unilateral LSCD and supports safety profile of this approach. The exact number of limbal stem cells ‘clock hours’, which can be safely harvested from donor eyes, has not been established. Based on this largest series of CLAU, authors recommend harvesting no more than 5 o’clock hours of limbal stem cells from donor eyes to avoid inducing LSCD.