Inbred corn line, designated KL18723N1, are disclosed. The disclosure relates to the seeds of inbred corn line KL18723N1, to the plants and plant parts of inbred corn line KL18723N1 and to methods for producing a corn plant, either inbred or hybrid, by crossing inbred corn line KL18723N1 with itself or another corn line. The disclosure also relates to products produced from the seeds, plants, or parts thereof, of inbred corn line KL18723N1 and/or of the hybrids produced using the inbred as a parent. The disclosure further relates to methods for producing a corn plant containing in its genetic material one or more transgenes and to the transgenic plants produced by that method and to methods for producing other corn lines derived from inbred corn line KL18723N1.