Space-efficient underfilling techniques for electronic assemblies are described. According to some such techniques, an underfilling method may comprise mounting an electronic element on a surface of a substrate, dispensing an underfill material upon the surface of the substrate within a dispense region for forming an underfill for the electronic element, and projecting curing rays upon at least a portion of the dispensed underfill material to inhibit an outward flow of dispensed underfill material from the dispense region, and the underfill material may comprise a non-visible light (NVL)-curable material. Other embodiments are described and claimed.