Successful formulation of low protein diets increases our flexibility in formulating practical diets, providing us with another tool to lower nitrogen output in the slurry and to reduce greenhouse gas emissions. This experiment compared the performance of pigs fed regular protein versus low protein diets. An intermediate protein diet was also employed. Average daily gain, average daily feed intake and feed efficiency were unaffected by dietary treatment. Most carcass characteristics, including index, lean yield and backfat thickness were unaffected by treatment; however, loin muscle thickness was increased on the low protein diet. Lower crude protein diets can be fed successfully without negatively impacting performance or carcass quality.