Are butterfly knives illegal in the state of va?

No, butterfly aka balisong knives are not illegal in the state/commonwealth of Virginia. Reason being they are not similar to other knives that are prohibited i.e. Dirks, Switchblades, Jet blades aka out the front automatics or OTF Autos. Therefore the knife is not illegal to own or carry openly or concealed. However some localities may have an ordinance against them, to know for sure you would need to ask your local state officials.