The hatchability of nest clean and dirty broiler hatching eggs which have been spray sanitized immediately following collection with the MS Technologies, Inc. Mini-Master/4000® were compared in four trials. Treatments were nonsanitized control, with eggs sanitized by immersion in water or spraying with water or with sanitizing solutions. Trials 1 and 2 utilized nest clean eggs only, while Trials 3 and 4 utilized both nest clean and dirty eggs. Hatch of eggs set and hatchability of fertile eggs were similar between nonsanitized control and all sanitized treatments used nest clean eggs or dirty hatching eggs. Nest clean eggs consistently had greater hatchability than dirty eggs, and sanitizing did not enhance or depress hatchability. The difference in hatchability between nest clean and dirty eggs was due to increased embryonic mortality following transfer into the hatcher for dirty eggs. In Trials 3 and 4, chick weight on day of hatch and at one week posthatch did not differ between nest clean and dirty eggs, or between sanitized and nonsanitized eggs. First week chick mortality was low (< 1%) and did not differ significantly between sanitized or nonsanitized nest clean or dirty hatching eggs.