Flexible multilayer substrate

A flexible multilayer substrate, comprising:

• a stacked body including a plurality of stacked resin layers extending in a longitudinal direction and defining a flexible portion;
• wherein
• the stacked body includes an innermost surface that is a surface located inside when both ends in the longitudinal direction are bent to come closer to each other, and an outermost surface that is a surface located outside when both ends in the longitudinal direction are bent to come closer to each other;
• a plurality of conductor patterns are arranged inside the stacked body and distributed over a surface of one or more of the plurality of resin layers;
• and
• a portion located on an innermost surface side with respect to a center plane of the stacked body in a thickness direction is a first portion, a portion located on an outermost surface side with respect to the center plane of the stacked body in a thickness direction is a second portion, and an area having a minimum spacing along the longitudinal direction between the conductor patterns arranged in a same plane, in all of the plurality of resin layers, is located in the second portion.