OBJECTIVE To compare central corneal thickness measurements as a function of contact lens wear in patients presenting for refractive surgery. METHODS Gimbel Eye Centre, Saskatoon, Saskatchewan, Canada. METHODS A retrospective study of charts yielded 634 eyes meeting the inclusion criterion. Pachymetry measurements of spectacle-wearing control eyes were compared to those of full-time soft contact lens wearers and rigid gas-permeable contact lens wearers. All measurements were taken with the DGH ultrasonic pachymeter by a single observer. RESULTS Soft contact lens wearers had a mean reduction in corneal thickness measurements of 22 micrometers compared to the control population (P =.00001). Rigid gas-permeable lens wearers had a reduction of 24 micrometers compared to the control population (P =.00001). CONCLUSIONS There was a clinically significant reduction in corneal thickness measurements associated with full-time contact lens wear.