Oligomer-grafted nanofiller compositions and composites including oligomer-grafted nanofillers are disclosed. An oligomer-grafted nanofiller composition for disposition in a polymer matrix, the polymeric matrix comprising polymers derived from a plurality of polymerizable units, can include a nanoparticle, one or more coupling groups bonded to the nanoparticle; and one or more oligomers bonded to the one or more coupling groups. In an embodiment the oligomer is derived from two or more polymerizable units, at least one polymerizable unit being at least substantially similar to at least one of the polymerizable units of the polymer matrix. In another embodiment the oligomer comprises two or more polymerizable units and improves dispersion, interfacial strength, or both dispersion and interfacial strength between the nanoparticle and the polymer matrix. Composites and methods are also disclosed.