Life-history theory posits resource-based trade-offs among traits such as growth, reproduction, and survival. These trade-offs are hypothesized to constrain the covariation of life-history traits along a slow-to-fast continuum. In this framework, populations of the same species that experience different habitat conditions are expected to diverge in life histories, and concomitantly, in metabolic and energetic traits that support life-history traits. Physiological hypotheses that result from this pace-of-life (POL) theory include predictions about immune function and metabolism, i.e., more reliance on and investment in acquired immune function and slower metabolic rates in slow POL individuals. Less clear is how stress physiology should associate with POL, in part because of the vast number of physiological markers that could be characterized as mediators of a stress response. Here we use long-studied natural populations of the western terrestrial garter snake (Thamnophis elegans) representing two life-history strategies from the vicinity of Eagle Lake, CA. From 2010-2019, we tested hypotheses that baseline and reactivity of plasma corticosterone, glucose, and leukocytes vary across years and with directionalities consistent with life-history theory. We found significant POL-specific annual variation in both baseline and stress-induced physiological traits generally in agreement with theoretical predictions.