The following highways are numbered 31D:
New York State Route 31A (NY 31A) is an east–west state highway located in the western part of New York in the United States. It serves as a southerly alternate route of NY 31 from the western part of Orleans County to the far western part of Monroe County. It diverges from NY 31 south of the village of Medina and parallels NY 31 eastward until it reconnects to its parent route southwest of the village of Brockport. While NY 31 passes through the villages of Medina, Albion, and Holley, NY 31A bypasses all three, serving sparsely populated areas to their south instead. The route intersects NY 98 south of Albion and NY 237 in Clarendon.
