Embodiments of the invention are directed to a springless athermal lens assembly. In one embodiment, a spacer of a springless athermal lens assembly may compensate for defocus of the camera system due to thermal expansion of the lens assembly through the coupling of a spacer to an inner barrel and an outer barrel. The inner barrel comprises a lens cell assembly and a body. The outer barrel comprises a body. The spacer comprises a body having an inner surface and an outer surface. The outer surface of the spacer body is configured to be physically coupled to outer barrel body and the inner surface of the spacer body is configured to be physically coupled to the inner barrel body. A retainer ring is configured to engage with the outer surface of the spacer body and provide a radial force against the outer surface of the spacer body to securably engage the inner surface of the spacer body with the inner barrel body.